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Shadfar S, Parakh S, Jamali MS, Atkin JD. Redox dysregulation as a driver for DNA damage and its relationship to neurodegenerative diseases. Transl Neurodegener 2023; 12:18. [PMID: 37055865 PMCID: PMC10103468 DOI: 10.1186/s40035-023-00350-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 03/16/2023] [Indexed: 04/15/2023] Open
Abstract
Redox homeostasis refers to the balance between the production of reactive oxygen species (ROS) as well as reactive nitrogen species (RNS), and their elimination by antioxidants. It is linked to all important cellular activities and oxidative stress is a result of imbalance between pro-oxidants and antioxidant species. Oxidative stress perturbs many cellular activities, including processes that maintain the integrity of DNA. Nucleic acids are highly reactive and therefore particularly susceptible to damage. The DNA damage response detects and repairs these DNA lesions. Efficient DNA repair processes are therefore essential for maintaining cellular viability, but they decline considerably during aging. DNA damage and deficiencies in DNA repair are increasingly described in age-related neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and Huntington's disease. Furthermore, oxidative stress has long been associated with these conditions. Moreover, both redox dysregulation and DNA damage increase significantly during aging, which is the biggest risk factor for neurodegenerative diseases. However, the links between redox dysfunction and DNA damage, and their joint contributions to pathophysiology in these conditions, are only just emerging. This review will discuss these associations and address the increasing evidence for redox dysregulation as an important and major source of DNA damage in neurodegenerative disorders. Understanding these connections may facilitate a better understanding of disease mechanisms, and ultimately lead to the design of better therapeutic strategies based on preventing both redox dysregulation and DNA damage.
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Affiliation(s)
- Sina Shadfar
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Macquarie University, Sydney, NSW, 2109, Australia.
| | - Sonam Parakh
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Macquarie University, Sydney, NSW, 2109, Australia
| | - Md Shafi Jamali
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Macquarie University, Sydney, NSW, 2109, Australia
| | - Julie D Atkin
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Macquarie University, Sydney, NSW, 2109, Australia.
- La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Melbourne, VIC, 3086, Australia.
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Evolutionary Origins of DNA Repair Pathways: Role of Oxygen Catastrophe in the Emergence of DNA Glycosylases. Cells 2021; 10:cells10071591. [PMID: 34202661 PMCID: PMC8307549 DOI: 10.3390/cells10071591] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 11/23/2022] Open
Abstract
It was proposed that the last universal common ancestor (LUCA) evolved under high temperatures in an oxygen-free environment, similar to those found in deep-sea vents and on volcanic slopes. Therefore, spontaneous DNA decay, such as base loss and cytosine deamination, was the major factor affecting LUCA’s genome integrity. Cosmic radiation due to Earth’s weak magnetic field and alkylating metabolic radicals added to these threats. Here, we propose that ancient forms of life had only two distinct repair mechanisms: versatile apurinic/apyrimidinic (AP) endonucleases to cope with both AP sites and deaminated residues, and enzymes catalyzing the direct reversal of UV and alkylation damage. The absence of uracil–DNA N-glycosylases in some Archaea, together with the presence of an AP endonuclease, which can cleave uracil-containing DNA, suggests that the AP endonuclease-initiated nucleotide incision repair (NIR) pathway evolved independently from DNA glycosylase-mediated base excision repair. NIR may be a relic that appeared in an early thermophilic ancestor to counteract spontaneous DNA damage. We hypothesize that a rise in the oxygen level in the Earth’s atmosphere ~2 Ga triggered the narrow specialization of AP endonucleases and DNA glycosylases to cope efficiently with a widened array of oxidative base damage and complex DNA lesions.
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Khodyreva S, Lavrik O. Non-canonical interaction of DNA repair proteins with intact and cleaved AP sites. DNA Repair (Amst) 2020; 90:102847. [DOI: 10.1016/j.dnarep.2020.102847] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 03/06/2020] [Accepted: 03/24/2020] [Indexed: 02/01/2023]
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Quiñones JL, Thapar U, Wilson SH, Ramsden DA, Demple B. Oxidative DNA-protein crosslinks formed in mammalian cells by abasic site lyases involved in DNA repair. DNA Repair (Amst) 2020; 87:102773. [PMID: 31945542 PMCID: PMC7065521 DOI: 10.1016/j.dnarep.2019.102773] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/23/2019] [Accepted: 12/24/2019] [Indexed: 01/15/2023]
Abstract
Free radical attack on C1' of deoxyribose forms the oxidized abasic (AP) site 2-deoxyribonolactone (dL). In vitro, dL traps the major base excision DNA repair enzyme DNA polymerase beta (Polβ) in covalent DNA-protein crosslinks (DPC) via the enzyme's N-terminal lyase activity acting on 5'-deoxyribose-5-phosphate residues. We previously demonstrated formation of Polβ-DPC in cells challenged with oxidants generating significant levels of dL. Proteasome inhibition under 1,10-copper-ortho-phenanthroline (CuOP) treatment significantly increased Polβ-DPC accumulation and trapped ubiquitin in the DPC, with Polβ accounting for 60-70 % of the total ubiquitin signal. However, the identity of the remaining oxidative ubiquityl-DPC remained unknown. In this report, we surveyed whether additional AP lyases are trapped in oxidative DPC in mammalian cells in culture. Poly(ADP-ribose) polymerase 1 (PARP1), Ku proteins, DNA polymerase λ (Polλ), and the bifunctional 8-oxoguanine DNA glycosylase 1 (OGG1), were all trapped in oxidative DPC in mammalian cells. We also observed significant trapping of Polλ, PARP1, and OGG1 in cells treated with the alkylating agent methylmethane sulfonate (MMS), in addition to dL-inducing agents. Ku proteins, in contrast, followed a pattern of trapping similar to that for Polβ: MMS failed to produce Ku-DPC, while treatment with CuOP or (less effectively) H2O2 gave rise to significant Ku-DPC. Unexpectedly, NEIL1 and NEIL3 were trapped following H2O2 treatment, but not detectably in cells exposed to CuOP. The half-life of all the AP lyase-DPC ranged from 15-60 min, consistent with their active repair. Accordingly, CuOP treatment under proteasome inhibition significantly increased the observed levels of DPC in cultured mammalian cells containing PARP1, Ku protein, Polλ, and OGG1 proteins. As seen for Polβ, blocking the proteasome led to the accumulation of DPC containing ubiquitin. Thus, the ubiquitin-dependent proteolytic mechanisms that control Polβ-DPC removal may also apply to a broad array of oxidative AP lyase-DPC, preventing their toxic accumulation in cells.
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Affiliation(s)
- Jason L Quiñones
- Department of Pharmacological Sciences, Stony Brook University, Renaissance School of Medicine, Basic Science Tower 8-140, Stony Brook, New York, 11794, USA
| | - Upasna Thapar
- Department of Pharmacological Sciences, Stony Brook University, Renaissance School of Medicine, Basic Science Tower 8-140, Stony Brook, New York, 11794, USA
| | - Samuel H Wilson
- Laboratory of Structural Biology, National Institute of Environmental Health Sciences, National Institutes of Health, PO Box 12233, Research Triangle Park, NC, 27709-2233, USA
| | - Dale A Ramsden
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Bruce Demple
- Department of Pharmacological Sciences, Stony Brook University, Renaissance School of Medicine, Basic Science Tower 8-140, Stony Brook, New York, 11794, USA.
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Matkarimov BT, Saparbaev MK. DNA Repair and Mutagenesis in Vertebrate Mitochondria: Evidence for Asymmetric DNA Strand Inheritance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1241:77-100. [DOI: 10.1007/978-3-030-41283-8_6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Mutation in DNA Polymerase Beta Causes Spontaneous Chromosomal Instability and Inflammation-Associated Carcinogenesis in Mice. Cancers (Basel) 2019; 11:cancers11081160. [PMID: 31412651 PMCID: PMC6721533 DOI: 10.3390/cancers11081160] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/01/2019] [Accepted: 08/08/2019] [Indexed: 12/15/2022] Open
Abstract
DNA polymerase beta (Pol β) is a key enzyme in the base excision repair (BER) pathway. Pol β is mutated in approximately 40% of human tumors in small-scale studies. The 5´-deoxyribose-5-phosphate (dRP) lyase domain of Pol β is responsible for DNA end tailoring to remove the 5’ phosphate group. We previously reported that the dRP lyase activity of Pol β is critical to maintain DNA replication fork stability and prevent cellular transformation. In this study, we tested the hypothesis that the human gastric cancer associated variant of Pol β (L22P) has the ability to promote spontaneous chromosomal instability and carcinogenesis in mice. We constructed a Pol β L22P conditional knock-in mouse model and found that L22P enhances hyperproliferation and DNA double strand breaks (DSBs) in stomach cells. Moreover, mouse embryonic fibroblasts (MEFs) derived from L22P mice frequently induce abnormal numbers of chromosomes and centrosome amplification, leading to chromosome segregation errors. Importantly, L22P mice exhibit chronic inflammation accompanied by stomach tumors. These data demonstrate that the human cancer-associated variant of Pol β can contribute to chromosomal instability and cancer development.
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Valenzuela L, Sepúlveda S, Ponce I, Galanti N, Cabrera G. The overexpression of TcAP1 endonuclease confers resistance to infective Trypanosoma cruzi trypomastigotes against oxidative DNA damage. J Cell Biochem 2018; 119:5985-5995. [PMID: 29575156 DOI: 10.1002/jcb.26795] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/20/2018] [Indexed: 01/22/2023]
Abstract
Trypanosoma cruzi, the causative agent of Chagas' disease survives to DNA damage generated by ROS/RNS inside to their different hosts. In recent eukaryotes, oxidative DNA damage is repaired mainly by the Base Excision Repair (BER) pathway, being essential the apurinic/apyrimidinic endonuclease activity. Using a pTREX-gfp vector, the nucleotide sequence that encodes T. cruzi AP endonuclease TcAP1 (orthologue of human APE1) and a putative TcAP1 dominant negative (TcAP1DN), were transfectedand expressed in T. cruzi epimastigotes. TcAP1-GFP and TcAP1DN-GFP were expressed in those modified epimastigotes and found in the parasite nucleus. The endonucleases were purified under native conditions and the AP endonuclease activity was evaluated. While TcAP1 presents the expected AP endonuclease activity TcAP1DN does not. Moreover, TcAP1DN partially inhibits in vitro TcAP1 enzymatic activity. Transfected epimastigotes expressing TcAP1-GFP and TcAP1DN-GFP were differentiated to infective trypomastigotes. The infective parasites maintained both proteins (TcAP1-GFP and TcAP1DN-GFP) in the nucleus. The overexpression of TcAP1-GFP in epimastigotes and trypomastigotes increases the viability of both parasite forms when exposed to oxidative stress while the expression of TcAP1DN-GFP did not show any in vivo inhibitory effect, suggesting that endogenous TcAP1 constitutive expression overcomes the TcAP1DN inhibitory activity. Our results show that TcAP1 is important for trypomastigote survival under oxidative conditions similar to those found in infected mammalian cells, then increasing its permanence in the infected cells and the possibility of development of Chagas disease.
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Affiliation(s)
- Lucía Valenzuela
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Programa de Doctorado en Ciencias Silvoagropecuarias y Veterinarias, Universidad de Chile, Santiago, Chile
| | - Soía Sepúlveda
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Iván Ponce
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Norbel Galanti
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Gonzalo Cabrera
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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Umeno A, Biju V, Yoshida Y. In vivo ROS production and use of oxidative stress-derived biomarkers to detect the onset of diseases such as Alzheimer's disease, Parkinson's disease, and diabetes. Free Radic Res 2017; 51:413-427. [PMID: 28372523 DOI: 10.1080/10715762.2017.1315114] [Citation(s) in RCA: 171] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Breakthroughs in biochemistry have furthered our understanding of the onset and progression of various diseases, and have advanced the development of new therapeutics. Oxidative stress and reactive oxygen species (ROS) are ubiquitous in biological systems. ROS can be formed non-enzymatically by chemical, photochemical and electron transfer reactions, or as the byproducts of endogenous enzymatic reactions, phagocytosis, and inflammation. Imbalances in ROS homeostasis, caused by impairments in antioxidant enzymes or non-enzymatic antioxidant networks, increase oxidative stress, leading to the deleterious oxidation and chemical modification of biomacromolecules such as lipids, DNA, and proteins. While many ROS are intracellular signaling messengers and most products of oxidative metabolisms are beneficial for normal cellular function, the elevation of ROS levels by light, hyperglycemia, peroxisomes, and certain enzymes causes oxidative stress-sensitive signaling, toxicity, oncogenesis, neurodegenerative diseases, and diabetes. Although the underlying mechanisms of these diseases are manifold, oxidative stress caused by ROS is a major contributing factor in their onset. This review summarizes the relationship between ROS and oxidative stress, with special reference to recent advancements in the detection of biomarkers related to oxidative stress. Further, we will introduce biomarkers for the early detection of neurodegenerative diseases and diabetes, with a focus on our recent work.
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Affiliation(s)
- Aya Umeno
- a Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Takamatsu , Kagawa , Japan
| | - Vasudevanpillai Biju
- a Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Takamatsu , Kagawa , Japan.,b Laboratory of Molecular Photonics, Research Institute for Electronic Science, Hokkaido University, N20W10 , Kita Ward, Sapporo , Japan
| | - Yasukazu Yoshida
- a Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Takamatsu , Kagawa , Japan
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Vale N, Gouveia MJ, Rinaldi G, Santos J, Santos LL, Brindley PJ, da Costa JMC. The role of estradiol metabolism in urogenital schistosomiasis-induced bladder cancer. Tumour Biol 2017; 39:1010428317692247. [PMID: 28345469 DOI: 10.1177/1010428317692247] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Urogenital schistosomiasis is a neglected tropical disease that can lead to bladder cancer. How urogenital schistosomiasis induces carcinogenesis remains unclear, although there is evidence that the human blood fluke Schistosoma haematobium, the infectious agent of urogenital schistosomiasis, releases estradiol-like metabolites. These kind of compounds have been implicated in other cancers. Aiming for enhanced understanding of the pathogenesis of the urogenital schistosomiasis-induced bladder cancer, here we review, interpret, and discuss findings of estradiol-like metabolites detected in both the parasite and in the human urine during urogenital schistosomiasis. Moreover, we predict pathways and enzymes that are involved in the production of these metabolites emphasizing their potential effects on the dysregulation of the tumor suppressor gene p53 expression during urogenital schistosomiasis. Enhanced understanding of these potential carcinogens may not only shed light on urogenital schistosomiasis-induced neoplasia of the bladder, but would also facilitate development of interventions and biomarkers for this and other infection-associated cancers at large.
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Affiliation(s)
- Nuno Vale
- 1 UCIBIO/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Maria J Gouveia
- 1 UCIBIO/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal.,2 Center for the Study of Animal Science, ICETA, University of Porto, Porto, Portugal
| | - Gabriel Rinaldi
- 3 Department of Microbiology, Immunology, & Tropical Medicine and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, George Washington University, Washington, DC, USA.,4 The Wellcome Trust Sanger Institute, Cambridge, UK
| | - Júlio Santos
- 5 Clínica da Sagrada Esperança, Luanda, Angola.,6 Experimental Pathology and Therapeutics Group, Research Center of Instituto Português de Oncologia, Porto, Portugal
| | - Lúcio Lara Santos
- 6 Experimental Pathology and Therapeutics Group, Research Center of Instituto Português de Oncologia, Porto, Portugal
| | - Paul J Brindley
- 3 Department of Microbiology, Immunology, & Tropical Medicine and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, George Washington University, Washington, DC, USA
| | - José M Correia da Costa
- 2 Center for the Study of Animal Science, ICETA, University of Porto, Porto, Portugal.,7 Department of Infectious Diseases, R&D Unit, National Health Institute Doutor Ricardo Jorge (INSA), Porto, Portugal
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Yang C, Sengupta S, Hegde PM, Mitra J, Jiang S, Holey B, Sarker AH, Tsai MS, Hegde ML, Mitra S. Regulation of oxidized base damage repair by chromatin assembly factor 1 subunit A. Nucleic Acids Res 2016; 45:739-748. [PMID: 27794043 PMCID: PMC5314755 DOI: 10.1093/nar/gkw1024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 10/13/2016] [Accepted: 10/19/2016] [Indexed: 01/27/2023] Open
Abstract
Reactive oxygen species (ROS), generated both endogenously and in response to exogenous stress, induce point mutations by mis-replication of oxidized bases and other lesions in the genome. Repair of these lesions via base excision repair (BER) pathway maintains genomic fidelity. Regulation of the BER pathway for mutagenic oxidized bases, initiated by NEIL1 and other DNA glycosylases at the chromatin level remains unexplored. Whether single nucleotide (SN)-BER of a damaged base requires histone deposition or nucleosome remodeling is unknown, unlike nucleosome reassembly which is shown to be required for other DNA repair processes. Here we show that chromatin assembly factor (CAF)-1 subunit A (CHAF1A), the p150 subunit of the histone H3/H4 chaperone, and its partner anti-silencing function protein 1A (ASF1A), which we identified in human NEIL1 immunoprecipitation complex, transiently dissociate from chromatin bound NEIL1 complex in G1 cells after induction of oxidative base damage. CHAF1A inhibits NEIL1 initiated repair in vitro. Subsequent restoration of the chaperone-BER complex in cell, presumably after completion of repair, suggests that histone chaperones sequester the repair complex for oxidized bases in non-replicating chromatin, and allow repair when oxidized bases are induced in the genome.
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Affiliation(s)
- Chunying Yang
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Shiladitya Sengupta
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030, USA .,Weill Cornell Medical College, Cornell University, New York, NY 10065, USA
| | - Pavana M Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Joy Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Shuai Jiang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Brooke Holey
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Altaf H Sarker
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Miaw-Sheue Tsai
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Muralidhar L Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030, USA.,Weill Cornell Medical College, Cornell University, New York, NY 10065, USA.,Houston Methodist Neurological Institute, Houston, TX 77030, USA
| | - Sankar Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030, USA .,Weill Cornell Medical College, Cornell University, New York, NY 10065, USA
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Hagemann M, Kern R, Maurino VG, Hanson DT, Weber APM, Sage RF, Bauwe H. Evolution of photorespiration from cyanobacteria to land plants, considering protein phylogenies and acquisition of carbon concentrating mechanisms. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:2963-76. [PMID: 26931168 DOI: 10.1093/jxb/erw063] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Photorespiration and oxygenic photosynthesis are intimately linked processes. It has been shown that under the present day atmospheric conditions cyanobacteria and all eukaryotic phototrophs need functional photorespiration to grow autotrophically. The question arises as to when this essential partnership evolved, i.e. can we assume a coevolution of both processes from the beginning or did photorespiration evolve later to compensate for the generation of 2-phosphoglycolate (2PG) due to Rubisco's oxygenase reaction? This question is mainly discussed here using phylogenetic analysis of proteins involved in the 2PG metabolism and the acquisition of different carbon concentrating mechanisms (CCMs). The phylogenies revealed that the enzymes involved in the photorespiration of vascular plants have diverse origins, with some proteins acquired from cyanobacteria as ancestors of the chloroplasts and others from heterotrophic bacteria as ancestors of mitochondria in the plant cell. Only phosphoglycolate phosphatase was found to originate from Archaea. Notably glaucophyte algae, the earliest branching lineage of Archaeplastida, contain more photorespiratory enzymes of cyanobacterial origin than other algal lineages or land plants indicating a larger initial contribution of cyanobacterial-derived proteins to eukaryotic photorespiration. The acquisition of CCMs is discussed as a proxy for assessing the timing of periods when photorespiratory activity may have been enhanced. The existence of CCMs also had marked influence on the structure and function of photorespiration. Here, we discuss evidence for an early and continuous coevolution of photorespiration, CCMs and photosynthesis starting from cyanobacteria via algae, to land plants.
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Affiliation(s)
- Martin Hagemann
- Universität Rostock, Institut für Biowissenschaften, Abteilung Pflanzenphysiologie, A.- Einstein-Str. 3, D-18051 Rostock, Germany
| | - Ramona Kern
- Universität Rostock, Institut für Biowissenschaften, Abteilung Pflanzenphysiologie, A.- Einstein-Str. 3, D-18051 Rostock, Germany
| | - Veronica G Maurino
- University of Düsseldorf, Institute of Developmental and Molecular Biology of Plants and Biotechnology, Cluster of Excellence on Plant Science (CEPLAS), Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - David T Hanson
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Andreas P M Weber
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Science (CEPLAS), Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Rowan F Sage
- Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, ON M5S3B2, Canada
| | - Hermann Bauwe
- Universität Rostock, Institut für Biowissenschaften, Abteilung Pflanzenphysiologie, A.- Einstein-Str. 3, D-18051 Rostock, Germany
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12
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Pestov NA, Gerasimova NS, Kulaeva OI, Studitsky VM. Structure of transcribed chromatin is a sensor of DNA damage. SCIENCE ADVANCES 2015; 1:e1500021. [PMID: 26601207 PMCID: PMC4646769 DOI: 10.1126/sciadv.1500021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 05/03/2015] [Indexed: 06/05/2023]
Abstract
Early detection and repair of damaged DNA is essential for cell functioning and survival. Although multiple cellular systems are involved in the repair of single-strand DNA breaks (SSBs), it remains unknown how SSBs present in the nontemplate strand (NT-SSBs) of DNA organized in chromatin are detected. The effect of NT-SSBs on transcription through chromatin by RNA polymerase II was studied. NT-SSBs localized in the promoter-proximal region of nucleosomal DNA and hidden in the nucleosome structure can induce a nearly quantitative arrest of RNA polymerase downstream of the break, whereas more promoter-distal SSBs moderately facilitate transcription. The location of the arrest sites on nucleosomal DNA suggests that formation of small intranucleosomal DNA loops causes the arrest. This mechanism likely involves relief of unconstrained DNA supercoiling accumulated during transcription through chromatin by NT-SSBs. These data suggest the existence of a novel chromatin-specific mechanism that allows the detection of NT-SSBs by the transcribing enzyme.
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Affiliation(s)
- Nikolay A. Pestov
- Department of Pharmacology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | | | - Olga I. Kulaeva
- Biology Faculty, Lomonosov Moscow State University, Moscow, Russia
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Vasily M. Studitsky
- Department of Pharmacology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
- Biology Faculty, Lomonosov Moscow State University, Moscow, Russia
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
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13
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Song J, Hong P, Liu C, Zhang Y, Wang J, Wang P. Human POLD1 modulates cell cycle progression and DNA damage repair. BMC BIOCHEMISTRY 2015; 16:14. [PMID: 26087769 PMCID: PMC4471906 DOI: 10.1186/s12858-015-0044-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 06/05/2015] [Indexed: 11/22/2022]
Abstract
Background The activity of eukaryotic DNA polymerase delta (Pol δ) plays an essential role in genome stability through its effects on DNA replication and repair. The p125 catalytic subunit of Pol δ is encoded by POLD1 gene in human cells. To clarify biological functions of POLD1, we investigated the effects of POLD1 overexpression or downregulation on cell proliferation, cell cycle progression, DNA synthesis and oxidative DNA damage induced by H2O2. Methods HEK293 cells were transfected with POLD1 expression plasmid or shRNA, cell proliferation, cell cycle progression, and DNA synthesis in HEK293 cells were analyzed. Results HEK293 cells were transfected with POLD1 expression plasmid or shRNA. POLD1 downregulation by shRNA suppressed cell proliferation, cell cycle progression, and DNA synthesis in HEK293 cells. However, POLD1 overexpression had no significant effects on these processes. Finally, comet assay showed that POLD1 downregulation led to increased DNA damage. Conclusions Our results suggest that human POLD1 plays important role in the regulation of cell cycle progression and DNA damage repair.
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Affiliation(s)
- Jing Song
- Department of Clinical Laboratory, Xuanwu Hospital Capital Medical University, No.45 Changchun Street, Xicheng District, Beijing, 100053, China.
| | - Ping Hong
- Department of Clinical Laboratory, Xuanwu Hospital Capital Medical University, No.45 Changchun Street, Xicheng District, Beijing, 100053, China.
| | - Chengeng Liu
- Department of Clinical Laboratory, Xuanwu Hospital Capital Medical University, No.45 Changchun Street, Xicheng District, Beijing, 100053, China.
| | - Yueqi Zhang
- Department of Clinical Laboratory, Xuanwu Hospital Capital Medical University, No.45 Changchun Street, Xicheng District, Beijing, 100053, China.
| | - Jinling Wang
- Department of Clinical Laboratory, Xuanwu Hospital Capital Medical University, No.45 Changchun Street, Xicheng District, Beijing, 100053, China.
| | - Peichang Wang
- Department of Clinical Laboratory, Xuanwu Hospital Capital Medical University, No.45 Changchun Street, Xicheng District, Beijing, 100053, China.
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Li M, Yu X. The role of poly(ADP-ribosyl)ation in DNA damage response and cancer chemotherapy. Oncogene 2015; 34:3349-56. [PMID: 25220415 PMCID: PMC4362780 DOI: 10.1038/onc.2014.295] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 07/31/2014] [Accepted: 08/01/2014] [Indexed: 12/12/2022]
Abstract
DNA damage is a deleterious threat, but occurs daily in all types of cells. In response to DNA damage, poly(ADP-ribosyl)ation, a unique post-translational modification, is immediately catalyzed by poly(ADP-ribose) polymerases (PARPs) at DNA lesions, which facilitates DNA damage repair. Recent studies suggest that poly(ADP-ribosyl)ation is one of the first steps of cellular DNA damage response and governs early DNA damage response pathways. Suppression of DNA damage-induced poly(ADP-ribosyl)ation by PARP inhibitors impairs early DNA damage response events. Moreover, PARP inhibitors are emerging as anti-cancer drugs in phase III clinical trials for BRCA-deficient tumors. In this review, we discuss recent findings on poly(ADP-ribosyl)ation in DNA damage response as well as the molecular mechanism by which PARP inhibitors selectively kill tumor cells with BRCA mutations.
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Affiliation(s)
- Mo Li
- Reproductive Medical Center, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China
- Division of Molecular Medicine and Genetics, Department of Internal Medicine, University of Michigan Medical School, 1150 W. Medical Center Drive, 5560 MSRBII, Ann Arbor, Michigan, 48109, USA
| | - Xiaochun Yu
- Division of Molecular Medicine and Genetics, Department of Internal Medicine, University of Michigan Medical School, 1150 W. Medical Center Drive, 5560 MSRBII, Ann Arbor, Michigan, 48109, USA
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15
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Keszenman DJ, Kolodiuk L, Baulch JE. DNA damage in cells exhibiting radiation-induced genomic instability. Mutagenesis 2015; 30:451-8. [PMID: 25711497 DOI: 10.1093/mutage/gev006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cells exhibiting radiation-induced genomic instability exhibit varied spectra of genetic and chromosomal aberrations. Even so, oxidative stress remains a common theme in the initiation and/or perpetuation of this phenomenon. Isolated oxidatively modified bases, abasic sites, DNA single strand breaks and clustered DNA damage are induced in normal mammalian cultured cells and tissues due to endogenous reactive oxygen species generated during normal cellular metabolism in an aerobic environment. While sparse DNA damage may be easily repaired, clustered DNA damage may lead to persistent cytotoxic or mutagenic events that can lead to genomic instability. In this study, we tested the hypothesis that DNA damage signatures characterised by altered levels of endogenous, potentially mutagenic, types of DNA damage and chromosomal breakage are related to radiation-induced genomic instability and persistent oxidative stress phenotypes observed in the chromosomally unstable progeny of irradiated cells. The measurement of oxypurine, oxypyrimidine and abasic site endogenous DNA damage showed differences in non-double-strand breaks (DSB) clusters among the three of the four unstable clones evaluated as compared to genomically stable clones and the parental cell line. These three unstable clones also had increased levels of DSB clusters. The results of this study demonstrate that each unstable cell line has a unique spectrum of persistent damage and lead us to speculate that alterations in DNA damage signaling and repair may be related to the perpetuation of genomic instability.
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Affiliation(s)
- Deborah J Keszenman
- Biosciences Department, Brookhaven National Laboratory, 50 Bell Avenue, Upton, NY 11973, USA, Laboratory of Medical and Environmental Radiobiology, Biophysical Chemistry Group, Department of Biological Sciences, CENUR del Noroeste, UdelaR, Rivera 1350, Salto 50000, Uruguay,
| | - Lucia Kolodiuk
- 107-112 CMM/BLL, Stony Brook University, Stony Brook, NY 11794, USA and
| | - Janet E Baulch
- Department of Radiation Oncology, University of California, Medical Sciences I, B149, Irvine, CA 92697, USA
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16
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Oxidatively induced DNA damage and its repair in cancer. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2014; 763:212-45. [PMID: 25795122 DOI: 10.1016/j.mrrev.2014.11.002] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 12/28/2022]
Abstract
Oxidatively induced DNA damage is caused in living organisms by endogenous and exogenous reactive species. DNA lesions resulting from this type of damage are mutagenic and cytotoxic and, if not repaired, can cause genetic instability that may lead to disease processes including carcinogenesis. Living organisms possess DNA repair mechanisms that include a variety of pathways to repair multiple DNA lesions. Mutations and polymorphisms also occur in DNA repair genes adversely affecting DNA repair systems. Cancer tissues overexpress DNA repair proteins and thus develop greater DNA repair capacity than normal tissues. Increased DNA repair in tumors that removes DNA lesions before they become toxic is a major mechanism for development of resistance to therapy, affecting patient survival. Accumulated evidence suggests that DNA repair capacity may be a predictive biomarker for patient response to therapy. Thus, knowledge of DNA protein expressions in normal and cancerous tissues may help predict and guide development of treatments and yield the best therapeutic response. DNA repair proteins constitute targets for inhibitors to overcome the resistance of tumors to therapy. Inhibitors of DNA repair for combination therapy or as single agents for monotherapy may help selectively kill tumors, potentially leading to personalized therapy. Numerous inhibitors have been developed and are being tested in clinical trials. The efficacy of some inhibitors in therapy has been demonstrated in patients. Further development of inhibitors of DNA repair proteins is globally underway to help eradicate cancer.
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17
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18
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Martínez-Fábregas J, Díaz-Moreno I, González-Arzola K, Janocha S, Navarro JA, Hervás M, Bernhardt R, Velázquez-Campoy A, Díaz-Quintana A, De la Rosa MA. Structural and functional analysis of novel human cytochrome C targets in apoptosis. Mol Cell Proteomics 2014; 13:1439-56. [PMID: 24643968 DOI: 10.1074/mcp.m113.034322] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Since the first description of apoptosis four decades ago, great efforts have been made to elucidate, both in vivo and in vitro, the molecular mechanisms involved in its regulation. Although the role of cytochrome c during apoptosis is well established, relatively little is known about its participation in signaling pathways in vivo due to its essential role during respiration. To obtain a better understanding of the role of cytochrome c in the onset of apoptosis, we used a proteomic approach based on affinity chromatography with cytochrome c as bait in this study. In this approach, novel cytochrome c interaction partners were identified whose in vivo interaction and cellular localization were facilitated through bimolecular fluorescence complementation. Modeling of the complex interface between cytochrome c and its counterparts indicated the involvement of the surface surrounding the heme crevice of cytochrome c, in agreement with the vast majority of known redox adducts of cytochrome c. However, in contrast to the high turnover rate of the mitochondrial cytochrome c redox adducts, those occurring under apoptosis led to the formation of stable nucleo-cytoplasmic ensembles, as inferred mainly from surface plasmon resonance and nuclear magnetic resonance measurements, which permitted us to corroborate the formation of such complexes in vitro. The results obtained suggest that human cytochrome c interacts with pro-survival, anti-apoptotic proteins following its release into the cytoplasm. Thus, cytochrome c may interfere with cell survival pathways and unlock apoptosis in order to prevent the spatial and temporal coexistence of antagonist signals.
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Affiliation(s)
- Jonathan Martínez-Fábregas
- From the ‡Instituto de Bioquímica Vegetal y Fotosíntesis, cicCartuja, Universidad de Sevilla-CSIC, Avda. Américo Vespucio 49, Sevilla 41092, Spain
| | - Irene Díaz-Moreno
- From the ‡Instituto de Bioquímica Vegetal y Fotosíntesis, cicCartuja, Universidad de Sevilla-CSIC, Avda. Américo Vespucio 49, Sevilla 41092, Spain
| | - Katiuska González-Arzola
- From the ‡Instituto de Bioquímica Vegetal y Fotosíntesis, cicCartuja, Universidad de Sevilla-CSIC, Avda. Américo Vespucio 49, Sevilla 41092, Spain
| | - Simon Janocha
- §Institut für Biochemie, Universität des Saarlandes, Campus B2.2, D-66123 Saarbrücken, Germany
| | - José A Navarro
- From the ‡Instituto de Bioquímica Vegetal y Fotosíntesis, cicCartuja, Universidad de Sevilla-CSIC, Avda. Américo Vespucio 49, Sevilla 41092, Spain
| | - Manuel Hervás
- From the ‡Instituto de Bioquímica Vegetal y Fotosíntesis, cicCartuja, Universidad de Sevilla-CSIC, Avda. Américo Vespucio 49, Sevilla 41092, Spain
| | - Rita Bernhardt
- §Institut für Biochemie, Universität des Saarlandes, Campus B2.2, D-66123 Saarbrücken, Germany
| | - Adrián Velázquez-Campoy
- ¶Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint-Unit IQFR-CSIC-BIFI, Department of Biochemistry and Molecular and Cell Biology, University of Zaragoza, Zaragoza, Spain, and Fundacion ARAID, Government of Aragon, Zaragoza, Spain
| | - Antonio Díaz-Quintana
- From the ‡Instituto de Bioquímica Vegetal y Fotosíntesis, cicCartuja, Universidad de Sevilla-CSIC, Avda. Américo Vespucio 49, Sevilla 41092, Spain
| | - Miguel A De la Rosa
- From the ‡Instituto de Bioquímica Vegetal y Fotosíntesis, cicCartuja, Universidad de Sevilla-CSIC, Avda. Américo Vespucio 49, Sevilla 41092, Spain;
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19
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Patel C, Dršata T, Lankaš F, Dumont E. Structure, Dynamics, and Interactions of a C4′-Oxidized Abasic Site in DNA: A Concomitant Strand Scission Reverses Affinities. Biochemistry 2013; 52:8115-25. [DOI: 10.1021/bi401268q] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chandan Patel
- Laboratoire
de Chimie, UMR 5182 CNRS, École Normale Supérieure de Lyon, 46, allée d’Italie, 69364 Lyon Cedex 07, France
| | - Tomàš Dršata
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
| | - Filip Lankaš
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
| | - Elise Dumont
- Laboratoire
de Chimie, UMR 5182 CNRS, École Normale Supérieure de Lyon, 46, allée d’Italie, 69364 Lyon Cedex 07, France
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20
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Smith JA, Park S, Krause JS, Banik NL. Oxidative stress, DNA damage, and the telomeric complex as therapeutic targets in acute neurodegeneration. Neurochem Int 2013; 62:764-75. [PMID: 23422879 DOI: 10.1016/j.neuint.2013.02.013] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 02/04/2013] [Accepted: 02/08/2013] [Indexed: 01/19/2023]
Abstract
Oxidative stress has been identified as an important contributor to neurodegeneration associated with acute CNS injuries and diseases such as spinal cord injury (SCI), traumatic brain injury (TBI), and ischemic stroke. In this review, we briefly detail the damaging effects of oxidative stress (lipid peroxidation, protein oxidation, etc.) with a particular emphasis on DNA damage. Evidence for DNA damage in acute CNS injuries is presented along with its downstream effects on neuronal viability. In particular, unchecked oxidative DNA damage initiates a series of signaling events (e.g. activation of p53 and PARP-1, cell cycle re-activation) which have been shown to promote neuronal loss following CNS injury. These findings suggest that preventing DNA damage might be an effective way to promote neuronal survival and enhance neurological recovery in these conditions. Finally, we identify the telomere and telomere-associated proteins (e.g. telomerase) as novel therapeutic targets in the treatment of neurodegeneration due to their ability to modulate the neuronal response to both oxidative stress and DNA damage.
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Affiliation(s)
- Joshua A Smith
- Division of Neurology, Department of Neurosciences, Medical University of South Carolina, 96 Jonathan Lucas St., Clinical Sciences Building Room 309, Charleston, SC 29425, USA.
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21
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Couvé S, Ishchenko AA, Fedorova OS, Ramanculov EM, Laval J, Saparbaev M. Direct DNA Lesion Reversal and Excision Repair in Escherichia coli. EcoSal Plus 2013; 5. [PMID: 26442931 DOI: 10.1128/ecosalplus.7.2.4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Indexed: 06/05/2023]
Abstract
Cellular DNA is constantly challenged by various endogenous and exogenous genotoxic factors that inevitably lead to DNA damage: structural and chemical modifications of primary DNA sequence. These DNA lesions are either cytotoxic, because they block DNA replication and transcription, or mutagenic due to the miscoding nature of the DNA modifications, or both, and are believed to contribute to cell lethality and mutagenesis. Studies on DNA repair in Escherichia coli spearheaded formulation of principal strategies to counteract DNA damage and mutagenesis, such as: direct lesion reversal, DNA excision repair, mismatch and recombinational repair and genotoxic stress signalling pathways. These DNA repair pathways are universal among cellular organisms. Mechanistic principles used for each repair strategies are fundamentally different. Direct lesion reversal removes DNA damage without need for excision and de novo DNA synthesis, whereas DNA excision repair that includes pathways such as base excision, nucleotide excision, alternative excision and mismatch repair, proceeds through phosphodiester bond breakage, de novo DNA synthesis and ligation. Cell signalling systems, such as adaptive and oxidative stress responses, although not DNA repair pathways per se, are nevertheless essential to counteract DNA damage and mutagenesis. The present review focuses on the nature of DNA damage, direct lesion reversal, DNA excision repair pathways and adaptive and oxidative stress responses in E. coli.
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22
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Neil AJ, Belotserkovskii BP, Hanawalt PC. Transcription blockage by bulky end termini at single-strand breaks in the DNA template: differential effects of 5' and 3' adducts. Biochemistry 2012; 51:8964-70. [PMID: 23066636 DOI: 10.1021/bi301240y] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
RNA polymerases from phage-infected bacteria and mammalian cells have been shown to bypass single-strand breaks (SSBs) with a single-nucleotide gap in the template DNA strand during transcription elongation; however, the SSB bypass efficiency varies significantly depending upon the backbone end chemistries at the break. Using a reconstituted T7 phage transcription system (T7 RNAP) and RNA polymerase II (RNAPII) in HeLa cell nuclear extracts, we observe a slight reduction in the level of transcription arrest at SSBs with no gap as compared to those with a single-nucleotide gap. We have shown that biotin and carbon-chain moieties linked to the 3' side, and in select cases the 5' side, of an SSB in the template strand strongly increase the level of transcription arrest when compared to unmodified SSBs. We also find that a small carbon-chain moiety linked to the upstream side of an SSB aids transcriptional bypass of SSBs for both T7 RNAP and RNAP II. Analysis of transcription across SSBs flanked by bulky 3' adducts reveals the ability of 3' end chemistries to arrest T7 RNAP in a size-dependent manner. T7 RNAP is also completely arrested when 3' adducts or 3'-phosphate groups are placed opposite 5'-phosphate groups at an SSB. We have also observed that a biotinylated thymine in the template strand (without a break) does not pose a strong block to transcription. Taken together, these results emphasize the importance of the size of 3', but usually not 5', end chemistries in arresting transcription at SSBs, substantiating the notion that bulky 3' lesions (e.g., topoisomerase cleavable complexes, 3'-phosphoglycolates, and 3'-unsaturated aldehydes) pose very strong blocks to transcribing RNA polymerases. These findings have implications for the processing of DNA damage through SSB intermediates and the mechanism of SSB bypass by T7 RNAP and mammalian RNAPII.
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Affiliation(s)
- Alexander J Neil
- Department of Biology, Stanford University, Stanford, California 94305, United States
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23
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DNA Repair and Cancer Therapy: Targeting APE1/Ref-1 Using Dietary Agents. JOURNAL OF ONCOLOGY 2012; 2012:370481. [PMID: 22997517 PMCID: PMC3444914 DOI: 10.1155/2012/370481] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 07/31/2012] [Indexed: 12/21/2022]
Abstract
Epidemiological studies have demonstrated the cancer protective effects of dietary agents and other natural compounds isolated from fruits, soybeans, and vegetables on neoplasia. Studies have also revealed the potential for these natural products to be combined with chemotherapy or radiotherapy for the more effective treatment of cancer. In this paper we discuss the potential for targeting the DNA base excision repair enzyme APE1/Ref-1 using dietary agents such as soy isoflavones, resveratrol, curcumin, and the vitamins ascorbate and α-tocopherol. We also discuss the potential role of soy isoflavones in sensitizing cancer cells to the effects of radiotherapy. A comprehensive review of the dual nature of APE1/Ref-1 in DNA repair and redox activation of cellular transcription factors, NF-κB and HIF-1α, is also discussed. Further research efforts dedicated to delineating the role of APE1/Ref-1 DNA repair versus redox activity in sensitizing cancer cells to conventional treatment are warranted.
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24
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Lirussi L, Antoniali G, Vascotto C, D'Ambrosio C, Poletto M, Romanello M, Marasco D, Leone M, Quadrifoglio F, Bhakat KK, Scaloni A, Tell G. Nucleolar accumulation of APE1 depends on charged lysine residues that undergo acetylation upon genotoxic stress and modulate its BER activity in cells. Mol Biol Cell 2012; 23:4079-96. [PMID: 22918947 PMCID: PMC3469522 DOI: 10.1091/mbc.e12-04-0299] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The functional importance of APE1 nucleolar accumulation is described. It is shown that acetylation of Lys27–35, affecting local conformation, regulates APE1 function by 1) controlling its interaction with NPM1 and rRNA and its nucleolar accumulation, 2) modulating K6/K7 acetylation status, and 3) promoting APE1 BER activity in cells. Apurinic/apyrimidinic endonuclease 1 (APE1) is the main abasic endonuclease in the base excision repair (BER) pathway of DNA lesions caused by oxidation/alkylation in mammalian cells; within nucleoli it interacts with nucleophosmin and rRNA through N-terminal Lys residues, some of which (K27/K31/K32/K35) may undergo acetylation in vivo. Here we study the functional role of these modifications during genotoxic damage and their in vivo relevance. We demonstrate that cells expressing a specific K-to-A multiple mutant are APE1 nucleolar deficient and are more resistant to genotoxic treatment than those expressing the wild type, although they show impaired proliferation. Of interest, we find that genotoxic treatment induces acetylation at these K residues. We also find that the charged status of K27/K31/K32/K35 modulates acetylation at K6/K7 residues that are known to be involved in the coordination of BER activity through a mechanism regulated by the sirtuin 1 deacetylase. Of note, structural studies show that acetylation at K27/K31/K32/K35 may account for local conformational changes on APE1 protein structure. These results highlight the emerging role of acetylation of critical Lys residues in regulating APE1 functions. They also suggest the existence of cross-talk between different Lys residues of APE1 occurring upon genotoxic damage, which may modulate APE1 subnuclear distribution and enzymatic activity in vivo.
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Affiliation(s)
- Lisa Lirussi
- Department of Medical and Biological Sciences, University of Udine, 33100 Udine, Italy
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25
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Collura A, Kemp PAVD, Boiteux S. Abasic sites linked to dUTP incorporation in DNA are a major cause of spontaneous mutations in absence of base excision repair and Rad17-Mec3-Ddc1 (9-1-1) DNA damage checkpoint clamp in Saccharomyces cerevisiae. DNA Repair (Amst) 2012; 11:294-303. [PMID: 22226374 DOI: 10.1016/j.dnarep.2011.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 11/21/2011] [Accepted: 12/09/2011] [Indexed: 12/28/2022]
Abstract
In Saccharomyces cerevisiae, inactivation of base excision repair (BER) AP endonucleases (Apn1p and Apn2p) results in constitutive phosphorylation of Rad53p and delay in cell cycle progression at the G2/M transition. These data led us to investigate genetic interactions between Apn1p, Apn2p and DNA damage checkpoint proteins. The results show that mec1 sml1, rad53 sml1 and rad9 is synthetic lethal with apn1 apn2. In contrast, apn1 apn2 rad17, apn1 apn2 ddc1 and apn1 apn2 rad24 triple mutants are viable, although they exhibit a strong Can(R) spontaneous mutator phenotype. In these strains, high Can(R) mutation rate is dependent upon functional uracil DNA N-glycosylase (Ung1p) and mutation spectra are dominated by AT to CG events. The results point to a role for Rad17-Mec3-Ddc1 (9-1-1) checkpoint clamp in the prevention of mutations caused by abasic (AP) sites linked to incorporation of dUTP into DNA followed by the excision of uracil by Ung1p. The antimutator role of the (9-1-1) clamp can either rely on its essential function in the induction of the DNA damage checkpoint or to another function that specifically impacts DNA repair and/or mutagenesis at AP sites. Here, we show that the abrogation of the DNA damage checkpoint is not sufficient to enhance spontaneous mutagenesis in the apn1 apn2 rad9 sml1 quadruple mutant. Spontaneous mutagenesis was also explored in strains deficient in the two major DNA N-glycosylases/AP-lyases (Ntg1p and Ntg2p). Indeed, apn1 apn2 ntg1 ntg2 exhibits a strong Ung1p-dependent Can(R) mutator phenotype with a spectrum enriched in AT to CG, like apn1 apn2 rad17. However, genetic analysis reveals that ntg1 ntg2 and rad17 are not epistatic for spontaneous mutagenesis in apn1 apn2. We conclude that under normal growth conditions, dUTP incorporation into DNA is a major source of AP sites that cause high genetic instability in the absence of BER factors (Apn1p, Apn2p, Ntg1p and Ntg2p) and Rad17-Mec3-Ddc1 (9-1-1) checkpoint clamp in yeast.
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Affiliation(s)
- Ada Collura
- CEA, iRCM, 18 route du Panorama, 92265 Fontenay aux Roses, France.
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26
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Petruccelli LA, Dupéré-Richer D, Pettersson F, Retrouvey H, Skoulikas S, Miller WH. Vorinostat induces reactive oxygen species and DNA damage in acute myeloid leukemia cells. PLoS One 2011; 6:e20987. [PMID: 21695163 PMCID: PMC3112218 DOI: 10.1371/journal.pone.0020987] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 05/17/2011] [Indexed: 11/18/2022] Open
Abstract
Histone deacetylase inhibitors (HDACi) are promising anti-cancer agents, however, their mechanisms of action remain unclear. In acute myeloid leukemia (AML) cells, HDACi have been reported to arrest growth and induce apoptosis. In this study, we elucidate details of the DNA damage induced by the HDACi vorinostat in AML cells. At clinically relevant concentrations, vorinostat induces double-strand breaks and oxidative DNA damage in AML cell lines. Additionally, AML patient blasts treated with vorinostat display increased DNA damage, followed by an increase in caspase-3/7 activity and a reduction in cell viability. Vorinostat-induced DNA damage is followed by a G2-M arrest and eventually apoptosis. We found that pre-treatment with the antioxidant N-acetyl cysteine (NAC) reduces vorinostat-induced DNA double strand breaks, G2-M arrest and apoptosis. These data implicate DNA damage as an important mechanism in vorinostat-induced growth arrest and apoptosis in both AML cell lines and patient-derived blasts. This supports the continued study and development of vorinostat in AMLs that may be sensitive to DNA-damaging agents and as a combination therapy with ionizing radiation and/or other DNA damaging agents.
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Affiliation(s)
- Luca A. Petruccelli
- Lady Davis Institute for Medical Research, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, Canada
| | - Daphné Dupéré-Richer
- Lady Davis Institute for Medical Research, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, Canada
| | - Filippa Pettersson
- Lady Davis Institute for Medical Research, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, Canada
| | - Hélène Retrouvey
- Lady Davis Institute for Medical Research, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, Canada
| | - Sophia Skoulikas
- Lady Davis Institute for Medical Research, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, Canada
| | - Wilson H. Miller
- Lady Davis Institute for Medical Research, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, Canada
- * E-mail:
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27
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Sukhanova MV, D'Herin C, van der Kemp PA, Koval VV, Boiteux S, Lavrik OI. Ddc1 checkpoint protein and DNA polymerase ɛ interact with nick-containing DNA repair intermediate in cell free extracts of Saccharomyces cerevisiae. DNA Repair (Amst) 2011; 10:815-25. [PMID: 21601535 DOI: 10.1016/j.dnarep.2011.04.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 04/12/2011] [Accepted: 04/22/2011] [Indexed: 10/18/2022]
Abstract
To characterize proteins that interact with base excision/single-strand interruption repair DNA intermediates in cell free extracts of Saccharomyces cerevisiae, we used a combination of photoaffinity labeling with the protein identification by MALDI-TOF-MS peptide mapping. Photoreactive analogue of dCTP, namely exo-N-[4-(4-azido-2,3,5,6,-tetrafluorobenzylidenehydrazinocarbonyl)-butylcarbamoyl]-2'-deoxycytidine-5'-triphosphate, and [(32)P]-labeled DNA duplex containing one nucleotide gap were used to generate nick-containing DNA with a photoreactive dCMP residue at the 3'-margin of the nick. This photoreactive DNA derivative was incubated with the yeast cell extract and after UV irradiation a number of proteins were labeled. Two of the crosslinked proteins were identified as the catalytic subunit of DNA polymerase ɛ and Ddc1 checkpoint protein. Labeling of DNA polymerase ɛ catalytic subunit with the nick-containing DNA repair intermediate indicates that the DNA polymerase is involved in the DNA repair synthesis in yeast, at least at DNA single-strand interruptions. Crosslinking of Ddc1 to DNA nicks took place independently of the other components of checkpoint clamp, Mec3 and Rad17, suggesting that the protein alone is able to recognize DNA single-strand breaks. Indeed, purified GST-tagged Ddc1 protein was efficiently crosslinked to nick-containing DNA. The interaction of Ddc1 with DNA nicks may provide a link between the DNA damage checkpoint and DNA base excision/single-strand breaks repair pathways in yeast. In addition, we found that absence of Ddc1 protein greatly influences the overall pattern of other proteins crosslinked to DNA nick. We suggested that this last effect of Ddc1 is at least partially due to its capacity to prevent proteolytic degradation of the DNA-protein adducts.
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Affiliation(s)
- Maria V Sukhanova
- Institute of Chemical Biology and Fundamental Medicine Siberian Division of the Russian Academy of Sciences, Prospect Lavrentieva 8, Novosibirsk 630090, Russia
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28
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Abstract
Aerobic life requires organisms to resist the damaging effects of ROS (reactive oxygen species), particularly during stress. Extensive research has established a detailed picture of how cells respond to oxidative stress. Attention is now focusing on identifying the key molecular targets of ROS, which cause killing when resistance is overwhelmed. Experimental criteria used to establish such targets have differing merits. Depending on the nature of the stress, ROS cause loss of essential cellular functions or gain of toxic functions. Essential targets on which life pivots during ROS stress include membrane lipid integrity and activity of ROS-susceptible proteins, including proteins required for faithful translation of mRNA. Protein oxidation also triggers accumulation of toxic protein aggregates or induction of apoptotic cell death. This burgeoning understanding of the principal ROS targets will offer new possibilities for therapy of ROS related diseases.
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29
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Schötz U, Heuer S, Caldwell RB, Zitzelsberger H. Genetic and biochemical analysis of base excision repair complexes participating in radiation-induced ROS damage repair. RADIATION PROTECTION DOSIMETRY 2011; 143:284-288. [PMID: 21109544 DOI: 10.1093/rpd/ncq400] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This work is part of the joint research project 'radiation-induced DNA damage' of the KVSF, a BMBF Initiative (maintenance of radiation biology expertise in Germany). The focus of the research is the mechanism of DNA repair, specifically damage repair aspects arising from radiation-induced reactive oxygen species production. The authors will systematically look at potential accessory proteins associated with primarily base excision repair using molecular and biochemical methods. The authors hope to gain knowledge on the initial response mechanisms to varying sources and doses of radiation. By using a highly sensitive marker system, it is intended to achieve a greater resolution of responses induced at lower doses. The work is of relevance for different human diseases caused by defects in DNA repair, e.g. spontaneous and radiation-related cancer. Beyond this, the risk of low radiation doses, for example, in the workplace is of relevance for radiation protection policy and decision-making thereof.
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Affiliation(s)
- Ulrike Schötz
- Department of Radiation Cytogenetics, German Research Center for Environmental Health (GmbH), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
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30
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Gredilla R. DNA damage and base excision repair in mitochondria and their role in aging. J Aging Res 2010; 2011:257093. [PMID: 21234332 PMCID: PMC3018712 DOI: 10.4061/2011/257093] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Accepted: 12/14/2010] [Indexed: 12/28/2022] Open
Abstract
During the last decades, our knowledge about the processes involved in the aging process has exponentially increased. However, further investigation will be still required to globally understand the complexity of aging. Aging is a multifactorial phenomenon characterized by increased susceptibility to cellular loss and functional decline, where mitochondrial DNA mutations and mitochondrial DNA damage response are thought to play important roles. Due to the proximity of mitochondrial DNA to the main sites of mitochondrial-free radical generation, oxidative stress is a major source of mitochondrial DNA mutations. Mitochondrial DNA repair mechanisms, in particular the base excision repair pathway, constitute an important mechanism for maintenance of mitochondrial DNA integrity. The results reviewed here support that mitochondrial DNA damage plays an important role in aging.
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Affiliation(s)
- Ricardo Gredilla
- Department of Physiology, Faculty of Medicine, Complutense University, Plaza Ramón y Cajal s/n. 28040 Madrid, Spain
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31
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Fung H, Demple B. Distinct roles of Ape1 protein in the repair of DNA damage induced by ionizing radiation or bleomycin. J Biol Chem 2010; 286:4968-77. [PMID: 21081487 DOI: 10.1074/jbc.m110.146498] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Ionizing radiation (IR) and bleomycin (BLM) are used to treat various types of cancers. Both agents generate cytotoxic double strand breaks (DSB) and abasic (apurinic/apyrimidinic (AP)) sites in DNA. The human AP endonuclease Ape1 acts on abasic or 3'-blocking DNA lesions such as those generated by IR or BLM. We examined the effect of siRNA-mediated Ape1 suppression on DNA repair and cellular resistance to IR or BLM in human B-lymphoblastoid TK6 cells and HCT116 colon tumor cells. Partial Ape1 deficiency (∼30% of normal levels) sensitized cells more dramatically to BLM than to IR cytotoxicity. In both cases, expression of the unrelated yeast AP endonuclease, Apn1, largely restored resistance. Ape1 deficiency increased DNA AP site accumulation due to IR treatment but reduced the number of DSB. In contrast, for BLM, there were more DSB under Ape1 deficiency, with little change in the accumulation of AP sites. Although the role of Ape1 in generating DSB was greater for IR, the enzyme facilitated removal of AP sites, which may mitigate the cytotoxic effects of IR. In contrast, BLM generates scattered AP sites, and the DSB have 3'-phosphoglycolate termini that require Ape1 processing. These DSB persist under Ape1 deficiency. Apoptosis induced by BLM (but not by IR) under Ape1 deficiency was partially p53-dependent, more dramatically in TK6 than HCT116 cells. Thus, Ape1 suppression or inhibition may be a more efficacious adjuvant for BLM than for IR cancer therapy, particularly for tumors with a functional p53 pathway.
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Affiliation(s)
- Hua Fung
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA
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32
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Hegde ML, Hazra TK, Mitra S. Functions of disordered regions in mammalian early base excision repair proteins. Cell Mol Life Sci 2010; 67:3573-87. [PMID: 20714778 DOI: 10.1007/s00018-010-0485-5] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 07/28/2010] [Indexed: 11/30/2022]
Abstract
Reactive oxygen species, generated endogenously and induced as a toxic response, produce several dozen oxidized or modified bases and/or single-strand breaks in mammalian and other genomes. These lesions are predominantly repaired via the conserved base excision repair (BER) pathway. BER is initiated with excision of oxidized or modified bases by DNA glycosylases leading to formation of abasic (AP) site or strand break at the lesion site. Structural analysis by experimental and modeling approaches shows the presence of a disordered segment commonly localized at the N- or C-terminus as a characteristic signature of mammalian DNA glycosylases which is absent in their bacterial prototypes. Recent studies on unstructured regions in DNA metabolizing proteins have indicated their essential role in interaction with other proteins and target DNA recognition. In this review, we have discussed the unique presence of disordered segments in human DNA glycosylases, and AP endonuclease involved in the processing of glycosylase products, and their critical role in regulating repair functions. These disordered segments also include sites for posttranslational modifications and nuclear localization signal. The teleological basis for their structural flexibility is discussed.
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Affiliation(s)
- Muralidhar L Hegde
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555-1079, USA
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33
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Brem R, Li F, Montaner B, Reelfs O, Karran P. DNA breakage and cell cycle checkpoint abrogation induced by a therapeutic thiopurine and UVA radiation. Oncogene 2010; 29:3953-63. [PMID: 20440263 PMCID: PMC2901207 DOI: 10.1038/onc.2010.140] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Revised: 03/05/2010] [Accepted: 03/18/2010] [Indexed: 12/13/2022]
Abstract
The frequency of squamous cell skin carcinoma in organ transplant patients is around 100-fold higher than normal. This dramatic example of therapy-related cancer reflects exposure to sunlight and to immunosuppressive drugs. Here, we show that the interaction between low doses of UVA, the major ultraviolet component of incident sunlight, and 6-TG, a UVA chromophore that is introduced into DNA by one of the most widely prescribed immunosuppressive drugs, causes DNA single- and double-strand breaks (DSB). S phase cells are particularly vulnerable to this DNA breakage and cells defective in rejoining of S-phase DSB are hypersensitive to the combination of low-dose UVA and DNA 6-TG. 6-TG/UVA-induced DNA lesions provoke canonical DNA damage responses involving activation of the ATM/Chk2 and ATR/Chk1 pathways and appropriate cell cycle checkpoints. Higher levels of photochemical DNA damage induce a proteasome-mediated degradation of Chk1 and checkpoint abrogation that is consistent with persistent unrepaired DNA damage. These findings indicate that the interaction between UVA and an immunosuppressant drug causes photochemical DNA lesions, including DNA breaks, and can compromise cell cycle checkpoints. These two properties could contribute to the high risk of sunlight-related skin cancer in long-term immunosuppressed patients.
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Affiliation(s)
| | | | - Beatriz Montaner
- Cancer Research UK London Research Institute, Clare Hall Laboratories, South Mimms, Herts EN6 3LD
| | | | - Peter Karran
- Cancer Research UK London Research Institute, Clare Hall Laboratories, South Mimms, Herts EN6 3LD
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34
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Liu P, Demple B. DNA repair in mammalian mitochondria: Much more than we thought? ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2010; 51:417-426. [PMID: 20544882 DOI: 10.1002/em.20576] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
For many years, the repair of most damage in mitochondrial DNA (mtDNA) was thought limited to short-patch base excision repair (SP-BER), which replaces a single nucleotide by the sequential action of DNA glycosylases, an apurinic/apyrimidinic (AP) endonuclease, the mitochondrial DNA polymerase gamma, an abasic lyase activity, and mitochondrial DNA ligase. However, the likely array of lesions inflicted on mtDNA by oxygen radicals and the possibility of replication errors and disruptions indicated that such a restricted repair repertoire would be inadequate. Recent studies have considerably expanded our knowledge of mtDNA repair to include long-patch base excision repair (LP-BER), mismatch repair, and homologous recombination and nonhomologous end-joining. In addition, elimination of mutagenic 8-oxodeoxyguanosine triphosphate (8-oxodGTP) helps prevent cell death due to the accumulation of this oxidation product in mtDNA. Although it was suspected for many years that irreparably damaged mtDNA might be targeted for degradation, only recently was clear evidence provided for this hypothesis. Therefore, multiple DNA repair pathways and controlled degradation of mtDNA function together to maintain the integrity of mitochondrial genome.
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Affiliation(s)
- Pingfang Liu
- Department of Radiation Oncology, Dana Farber Cancer Institute, Boston, Massachusetts, USA
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35
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Iyama T, Abolhassani N, Tsuchimoto D, Nonaka M, Nakabeppu Y. NUDT16 is a (deoxy)inosine diphosphatase, and its deficiency induces accumulation of single-strand breaks in nuclear DNA and growth arrest. Nucleic Acids Res 2010; 38:4834-43. [PMID: 20385596 PMCID: PMC2919730 DOI: 10.1093/nar/gkq249] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Nucleotides function in a variety of biological reactions; however, they can undergo various chemical modifications. Such modified nucleotides may be toxic to cells if not eliminated from the nucleotide pools. We performed a screen for modified-nucleotide binding proteins and identified human nucleoside diphosphate linked moiety X-type motif 16 (NUDT16) protein as an inosine triphosphate (ITP)/xanthosine triphosphate (XTP)/GTP-binding protein. Recombinant NUDT16 hydrolyzes purine nucleoside diphosphates to the corresponding nucleoside monophosphates. Among 29 nucleotides examined, the highest kcat/Km values were for inosine diphosphate (IDP) and deoxyinosine diphosphate (dIDP). Moreover, NUDT16 moderately hydrolyzes (deoxy)inosine triphosphate ([d]ITP). NUDT16 is mostly localized in the nucleus, and especially in the nucleolus. Knockdown of NUDT16 in HeLa MR cells caused cell cycle arrest in S-phase, reduced cell proliferation, increased accumulation of single-strand breaks in nuclear DNA as well as increased levels of inosine in RNA. We thus concluded that NUDT16 is a (deoxy)inosine diphosphatase that may function mainly in the nucleus to protect cells from deleterious effects of (d)ITP.
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Affiliation(s)
- Teruaki Iyama
- Division of Neurofunctional Genomics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka, Japan
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36
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Sedelnikova OA, Redon CE, Dickey JS, Nakamura AJ, Georgakilas AG, Bonner WM. Role of oxidatively induced DNA lesions in human pathogenesis. Mutat Res 2010; 704:152-9. [PMID: 20060490 PMCID: PMC3074954 DOI: 10.1016/j.mrrev.2009.12.005] [Citation(s) in RCA: 249] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 12/08/2009] [Accepted: 12/14/2009] [Indexed: 02/06/2023]
Abstract
Genome stability is essential for maintaining cellular and organismal homeostasis, but it is subject to many threats. One ubiquitous threat is from a class of compounds known as reactive oxygen species (ROS), which can indiscriminately react with many cellular biomolecules including proteins, lipids, and DNA to produce a variety of oxidative lesions. These DNA oxidation products are a direct risk to genome stability, and of particular importance are oxidative clustered DNA lesions (OCDLs), defined as two or more oxidative lesions present within 10 bp of each other. ROS can be produced by exposure of cells to exogenous environmental agents including ionizing radiation, light, chemicals, and metals. In addition, they are produced by cellular metabolism including mitochondrial ATP generation. However, ROS also serve a variety of critical cellular functions and optimal ROS levels are maintained by multiple cellular antioxidant defenses. Oxidative DNA lesions can be efficiently repaired by base excision repair or nucleotide excision repair. If ROS levels increase beyond the capacity of its antioxidant defenses, the cell's DNA repair capacity can become overwhelmed, leading to the accumulation of oxidative DNA damage products including OCDLs, which are more difficult to repair than individual isolated DNA damage products. Here we focus on the induction and repair of OCDLs and other oxidatively induced DNA lesions. If unrepaired, these lesions can lead to the formation of mutations, DNA DSBs, and chromosome abnormalities. We discuss the roles of these lesions in human pathologies including aging and cancer, and in bystander effects.
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Affiliation(s)
- Olga A Sedelnikova
- Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, 9000 Rockville Pike, Bethesda, MD 20892, USA.
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37
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Gredilla R, Bohr VA, Stevnsner T. Mitochondrial DNA repair and association with aging--an update. Exp Gerontol 2010; 45:478-88. [PMID: 20096766 DOI: 10.1016/j.exger.2010.01.017] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 01/10/2010] [Accepted: 01/14/2010] [Indexed: 01/07/2023]
Abstract
Mitochondrial DNA is constantly exposed to oxidative injury. Due to its location close to the main site of reactive oxygen species, the inner mitochondrial membrane, mtDNA is more susceptible than nuclear DNA to oxidative damage. The accumulation of DNA damage is thought to play a critical role in the aging process and to be particularly deleterious in post-mitotic cells. Thus, DNA repair is an important mechanism for maintenance of genomic integrity. Despite the importance of mitochondria in the aging process, it was thought for many years that mitochondria lacked an enzymatic DNA repair system comparable to that in the nuclear compartment. However, it is now well established that DNA repair actively takes place in mitochondria. Oxidative DNA damage processing, base excision repair mechanisms were the first to be described in these organelles, and consequently the best understood. However, new proteins and novel DNA repair pathways, thought to be exclusively present in the nucleus, have recently been described also to be present in mitochondria. Here we review the main mitochondrial DNA repair pathways and their association with the aging process.
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Affiliation(s)
- Ricardo Gredilla
- Danish Center for Molecular Gerontology, Department of Molecular Biology, Aarhus University, C.F. Moellers allé 3, Aarhus C, Denmark
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38
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Tdp1 protects against oxidative DNA damage in non-dividing fission yeast. EMBO J 2009; 28:632-40. [PMID: 19197239 DOI: 10.1038/emboj.2009.9] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Accepted: 01/02/2009] [Indexed: 11/08/2022] Open
Abstract
In humans, a mutation in the tyrosyl-DNA phosphodiesterase (Tdp1) is responsible for the recessively inherited syndrome spinocerebellar ataxia with axonal neuropathy (SCAN1). Tdp1 is a well-conserved DNA repair enzyme, which processes modified 3' phospho-DNA adducts in vitro. Here, we report that in the yeast Schizosaccharomyces pombe, tdp1 mutant cells progressively accumulate DNA damage and rapidly lose viability in a physiological G0/quiescent state. Remarkably, this effect is independent of topoisomerase I function. Moreover, we provide evidence that Tdp1, with the polynucleotide kinase (Pnk1), processes the same naturally occurring 3'-ends, produced from oxidative DNA damage in G0. We also found that one half of the dead cells lose their nuclear DNA. Nuclear DNA degradation is genetically programmed and mainly depends on the two DNA damage checkpoint responses, ATM/Tel1 and ATR/Rad3, reminiscent to programmed cell death. Diminishing the respiration rate or treating cells with a low concentration of antioxidants rescues the quiescent tdp1 mutant cells. These findings suggest that mitochondrial respiration causes neuronal cell death in the SCAN1 syndrome and in other neurological disorders.
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39
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Son MY, Jun HI, Lee KG, Demple B, Sung JS. Biochemical evaluation of genotoxic biomarkers for 2-deoxyribonolactone-mediated cross-link formation with histones. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2009; 72:1311-1317. [PMID: 20077202 DOI: 10.1080/15287390903212402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Numerous environmental carcinogens involve radical formation interacting with DNA to produce 2-deoxyribonolactone (dL), a major type of oxidized abasic site, implicated in DNA strand breaks, mutagenesis, and formation of covalent DNA-protein cross-links (DPC). Studies showed major dL-specific DPC occurred due to reactions with DNA polymerase beta (Polbeta) dependent on native conformation, while other DPC formed involved nonenzymatic reactions of DNA binding proteins with dL lesions. Polbeta appeared to play a major role in alleviating the cytotoxic effects of neocarzinostatin, which was used as a dL-producing agent. When a duplex DNA containing a dL at a site-specific position was incubated with purified histones, DPC were formed between dL and each histone protein, including H1, H2A, H2B, H3, and H4. Comparative kinetic analysis of DPC formation with histones and Polbeta revealed two distinct mechanisms of dL-mediated DPC formation. The rate of DPC formation with Polbeta was approximately two orders of magnitude higher than that with various histone proteins. These results indicate that catalytic activity of Polbeta mediates rapid DPC formation between dL and this DNA repair enzyme, whereas nonenzymatic reactions of dL with histones form DPC more slowly. The abundance of histones and their constant interaction with DNA may nevertheless yield significant levels of DPC with dL, as biomarkers of dL-induced cytotoxicity. Overall, data suggest that occurrence of dL-mediated DPC with histones may contribute to the genotoxic effects of dL in DNA.
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Affiliation(s)
- Mi-Young Son
- Department of Life Science, Dongguk University, Seoul, Korea
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40
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Transcription-coupled DNA repair: two decades of progress and surprises. Nat Rev Mol Cell Biol 2008; 9:958-70. [PMID: 19023283 DOI: 10.1038/nrm2549] [Citation(s) in RCA: 777] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Expressed genes are scanned by translocating RNA polymerases, which sensitively detect DNA damage and initiate transcription-coupled repair (TCR), a subpathway of nucleotide excision repair that removes lesions from the template DNA strands of actively transcribed genes. Human hereditary diseases that present a deficiency only in TCR are characterized by sunlight sensitivity without enhanced skin cancer. Although multiple gene products are implicated in TCR, we still lack an understanding of the precise signals that can trigger this pathway. Futile cycles of TCR at naturally occurring non-canonical DNA structures might contribute to genomic instability and genetic disease.
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41
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Abstract
Life evolved in an anaerobic world; therefore, fundamental enzymatic mechanisms and biochemical pathways were refined and integrated into metabolism in the absence of any selective pressure to avoid reactivity with oxygen. After photosystem II appeared, environmental oxygen levels rose very slowly. During this time, microorganisms acquired oxygen tolerance by jettisoning enzymes that use glycyl radicals and exposed low-potential iron-sulfur clusters, which can be directly poisoned by oxygen. They also developed mechanisms to defend themselves against superoxide (O(2)()) and hydrogen peroxide, partially reduced oxygen species that are generated as inadvertent by-products of aerobic metabolism. Contemporary organisms have inherited both the vulnerabilities and the defenses of these ancestral microbes. Current research seeks to identify these, and bacteria comprise an exceptionally accessible experimental system that has provided many of the answers. This manuscript reviews recent developments and identifies remaining puzzles.
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Affiliation(s)
- James A Imlay
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA.
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42
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Abstract
Hereditary defects in the repair of DNA damage are implicated in a variety of diseases, many of which are typified by neurological dysfunction and/or increased genetic instability and cancer. Of the different types of DNA damage that arise in cells, single-strand breaks (SSBs) are the most common, arising at a frequency of tens of thousands per cell per day from direct attack by intracellular metabolites and from spontaneous DNA decay. Here, the molecular mechanisms and organization of the DNA-repair pathways that remove SSBs are reviewed and the connection between defects in these pathways and hereditary neurodegenerative disease are discussed.
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Affiliation(s)
- Keith W Caldecott
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK.
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43
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Eot-Houllier G, Fulcrand G, Magnaghi-Jaulin L, Jaulin C. Histone deacetylase inhibitors and genomic instability. Cancer Lett 2008; 274:169-76. [PMID: 18635312 DOI: 10.1016/j.canlet.2008.06.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Revised: 06/03/2008] [Accepted: 06/04/2008] [Indexed: 12/15/2022]
Abstract
Histone deacetylase inhibitors (HDACIs) are a promising new class of anticancer drugs. However, their mechanism of action has not been fully elucidated. Most studies have investigated the effect of HDACIs on the regulation of gene transcription. HDAC inhibition also leads to genomic instability by a variety of mechanisms. This phenomenon, which has been largely overlooked, may contribute to the cytotoxic effects of these drugs. Indeed, HDACIs sensitize DNA to exogenous genotoxic damage and induce the generation of reactive oxygen species. Moreover, HDACIs target mitosis resulting in chromosome segregation defects. Here, we review the effects of HDACI treatment on DNA damage and repair, and chromosome segregation control.
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Affiliation(s)
- Grégory Eot-Houllier
- Groupe Microtubules et Cycle Cellulaire, Institut de Génétique Humaine, CNRS UPR 1142, rue de la cardonille, 34396 Montpellier cedex 5, France
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44
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Removal of oxidative DNA damage via FEN1-dependent long-patch base excision repair in human cell mitochondria. Mol Cell Biol 2008; 28:4975-87. [PMID: 18541666 DOI: 10.1128/mcb.00457-08] [Citation(s) in RCA: 155] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Repair of oxidative DNA damage in mitochondria was thought limited to short-patch base excision repair (SP-BER) replacing a single nucleotide. However, certain oxidative lesions cannot be processed by SP-BER. Here we report that 2-deoxyribonolactone (dL), a major type of oxidized abasic site, inhibits replication by mitochondrial DNA (mtDNA) polymerase gamma and interferes with SP-BER by covalently trapping polymerase gamma during attempted dL excision. However, repair of dL was detected in human mitochondrial extracts, and we show that this repair is via long-patch BER (LP-BER) dependent on flap endonuclease 1 (FEN1), not previously known to be present in mitochondria. FEN1 was retained in protease-treated mitochondria and detected in mitochondrial nucleoids that contain known mitochondrial replication and transcription proteins. Results of immunofluorescence and subcellular fractionation studies were also consistent with the presence of FEN1 in the mitochondria of intact cells. Immunodepletion experiments showed that the LP-BER activity of mitochondrial extracts was strongly diminished in parallel with the removal of FEN1, although some activity remained, suggesting the presence of an additional flap-removing enzyme. Biological evidence for a FEN1 role in repairing mitochondrial oxidative DNA damage was provided by RNA interference experiments, with the extent of damage greater and the recovery slower in FEN1-depleted cells than in control cells. The mitochondrial LP-BER pathway likely plays important roles in repairing dL lesions and other oxidative lesions and perhaps in normal mtDNA replication.
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45
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Bernstein NK, Karimi-Busheri F, Rasouli-Nia A, Mani R, Dianov G, Glover JNM, Weinfeld M. Polynucleotide kinase as a potential target for enhancing cytotoxicity by ionizing radiation and topoisomerase I inhibitors. Anticancer Agents Med Chem 2008; 8:358-67. [PMID: 18473721 PMCID: PMC2962422 DOI: 10.2174/187152008784220311] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The cytotoxicity of many antineoplastic agents is due to their capacity to damage DNA and there is evidence indicating that DNA repair contributes to the cellular resistance to such agents. DNA strand breaks constitute a significant proportion of the lesions generated by a broad range of genotoxic agents, either directly, or during the course of DNA repair. Strand breaks that are caused by many agents including ionizing radiation, topoisomerase I inhibitors, and DNA repair glycosylases such as NEIL1 and NEIL2, often contain 5'-hydroxyl and/or 3'-phosphate termini. These ends must be converted to 5'-phosphate and 3'-hydroxyl termini in order to allow DNA polymerases and ligases to catalyze repair synthesis and strand rejoining. A key enzyme involved in this end-processing is polynucleotide kinase (PNK), which possesses two enzyme activities, a DNA 5'-kinase activity and a 3'-phosphatase activity. PNK participates in the single-strand break repair pathway and the non-homologous end joining pathway for double-strand break repair. RNAi-mediated down-regulation of PNK renders cells more sensitive to ionizing radiation and camptothecin, a topoisomerase I inhibitor. Structural analysis of PNK revealed the protein is composed of three domains, the kinase domain at the C-terminus, the phosphatase domain in the centre and a forkhead associated (FHA) domain at the N-terminus. The FHA domain plays a critical role in the binding of PNK to other DNA repair proteins. Thus each PNK domain may be a suitable target for small molecule inhibition to effectively reduce resistance to ionizing radiation and topoisomerase I inhibitors.
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Affiliation(s)
- N K Bernstein
- Department of Biochemistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
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46
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Hanawalt PC. Emerging links between premature ageing and defective DNA repair. Mech Ageing Dev 2008; 129:503-5. [PMID: 18440595 DOI: 10.1016/j.mad.2008.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 03/10/2008] [Accepted: 03/12/2008] [Indexed: 11/15/2022]
Affiliation(s)
- Philip C Hanawalt
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305-5020, USA.
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47
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Hegde ML, Hazra TK, Mitra S. Early steps in the DNA base excision/single-strand interruption repair pathway in mammalian cells. Cell Res 2008; 18:27-47. [PMID: 18166975 DOI: 10.1038/cr.2008.8] [Citation(s) in RCA: 461] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Base excision repair (BER) is an evolutionarily conserved process for maintaining genomic integrity by eliminating several dozen damaged (oxidized or alkylated) or inappropriate bases that are generated endogenously or induced by genotoxicants, predominantly, reactive oxygen species (ROS). BER involves 4-5 steps starting with base excision by a DNA glycosylase, followed by a common pathway usually involving an AP-endonuclease (APE) to generate 3' OH terminus at the damage site, followed by repair synthesis with a DNA polymerase and nick sealing by a DNA ligase. This pathway is also responsible for repairing DNA single-strand breaks with blocked termini directly generated by ROS. Nearly all glycosylases, far fewer than their substrate lesions particularly for oxidized bases, have broad and overlapping substrate range, and could serve as back-up enzymes in vivo. In contrast, mammalian cells encode only one APE, APE1, unlike two APEs in lower organisms. In spite of overall similarity, BER with distinct subpathways in the mammals is more complex than in E. coli. The glycosylases form complexes with downstream proteins to carry out efficient repair via distinct subpathways one of which, responsible for repair of strand breaks with 3' phosphate termini generated by the NEIL family glycosylases or by ROS, requires the phosphatase activity of polynucleotide kinase instead of APE1. Different complexes may utilize distinct DNA polymerases and ligases. Mammalian glycosylases have nonconserved extensions at one of the termini, dispensable for enzymatic activity but needed for interaction with other BER and non-BER proteins for complex formation and organelle targeting. The mammalian enzymes are sometimes covalently modified which may affect activity and complex formation. The focus of this review is on the early steps in mammalian BER for oxidized damage.
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Affiliation(s)
- Muralidhar L Hegde
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-1079, USA
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48
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Abstract
Life evolved in an anaerobic world; therefore, fundamental enzymatic mechanisms and biochemical pathways were refined and integrated into metabolism in the absence of any selective pressure to avoid reactivity with oxygen. After photosystem II appeared, environmental oxygen levels rose very slowly. During this time, microorganisms acquired oxygen tolerance by jettisoning enzymes that use glycyl radicals and exposed low-potential iron-sulfur clusters, which can be directly poisoned by oxygen. They also developed mechanisms to defend themselves against superoxide (O(2)()) and hydrogen peroxide, partially reduced oxygen species that are generated as inadvertent by-products of aerobic metabolism. Contemporary organisms have inherited both the vulnerabilities and the defenses of these ancestral microbes. Current research seeks to identify these, and bacteria comprise an exceptionally accessible experimental system that has provided many of the answers. This manuscript reviews recent developments and identifies remaining puzzles.
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Affiliation(s)
- James A Imlay
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA.
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49
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Georgakilas AG. Processing of DNA damage clusters in human cells: current status of knowledge. MOLECULAR BIOSYSTEMS 2007; 4:30-5. [PMID: 18075671 DOI: 10.1039/b713178j] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Eukaryotic cells exposed to DNA damaging agents activate important defensive pathways by inducing multiple proteins involved in DNA repair, cell cycle checkpoint control and potentially apoptosis. After the acceptance of the hypothesis that oxidatively generated clustered DNA lesions (OCDL: closely spaced DNA lesions) can be induced even by low doses of ionizing radiation or even endogenously, and significant advances have been made in the understanding of the biochemistry underlying the repair of closely spaced DNA lesions, many questions still remain unanswered. The major questions that have to be answered in the near future are: 1) how human cells process these types of DNA damage if they repair them at all, 2) under what conditions a double strand break (DSB) may be created during the processing of two closely spaced DNA lesions and 3) what type of repair protein interactions govern the processing of complex DNA damage? The data existing so far on human cells and tissues are very limited and in some cases contradicting. All of them though agree however on the major importance of gaining mechanistic insights on the pathways used by the cell to confront and process complex DNA damage located in a small DNA volume and the need of more in depth analytical studies. We selectively review recently-obtained data on the processing of non-DSB DNA damage clusters in human cells and tissues and discuss the current status of knowledge in the field.
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Affiliation(s)
- Alexandros G Georgakilas
- Department of Biology, Thomas Harriot College of Arts and Sciences, East Carolina University, Greenville NC 27858, USA.
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Vidal AE, Harkiolaki M, Gallego C, Castillo-Acosta VM, Ruiz-Pérez LM, Wilson K, González-Pacanowska D. Crystal Structure and DNA Repair Activities of the AP Endonuclease from Leishmania major. J Mol Biol 2007; 373:827-38. [PMID: 17870086 DOI: 10.1016/j.jmb.2007.08.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Revised: 07/24/2007] [Accepted: 08/01/2007] [Indexed: 12/31/2022]
Abstract
Apurinic/apyrimidinic endonucleases initiate the repair of abasic sites produced either spontaneously, from attack of bases by reactive oxygen species or as intermediates during base excision repair. The catalytic properties and crystal structure of Leishmania major apurinic/apyrimidinic endonuclease are described and compared with those of human APE1 and bacterial exonuclease III. The purified enzyme is shown to possess apurinic/apyrimidinic endonuclease activity of the same order as eukaryotic and prokaryotic counterparts and an equally robust 3'-phosphodiesterase activity. Consistent with this, expression of the L. major endonuclease confers resistance to both methyl methane sulphonate and H2O2 in Escherichia coli repair-deficient mutants while expression of the human homologue only reverts methyl methane sulphonate sensitivity. Structural analyses and modelling of the enzyme-DNA complex demonstrates a high degree of conservation to previously characterized homologues, although subtle differences in the active site geometry might account for the high 3'-phosphodiesterase activity. Our results confirm that the L. major's enzyme is a key element in mediating repair of apurinic/apyrimidinic sites and 3'-blocked termini and therefore must play an important role in the survival of kinetoplastid parasites after exposure to the highly oxidative environment within the host macrophage.
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Affiliation(s)
- Antonio E Vidal
- Instituto de Parasitología y Biomedicina López-Neyra, Consejo Superior de Investigaciones Científicas, Avda. del Conocimiento s/n, 18100 Armilla, Granada, Spain
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