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Abstract
Nucleotide excision repair (NER) is a highly conserved mechanism to remove helix-distorting DNA lesions. A major substrate for NER is DNA damage caused by environmental genotoxins, most notably ultraviolet radiation. Xeroderma pigmentosum, Cockayne syndrome and trichothiodystrophy are three human disorders caused by inherited defects in NER. The symptoms and severity of these diseases vary dramatically, ranging from profound developmental delay to cancer predisposition and accelerated ageing. All three syndromes include developmental abnormalities, indicating an important role for optimal transcription and for NER in protecting against spontaneous DNA damage during embryonic development. Here, we review the current knowledge on genes that function in NER that also affect embryonic development, in particular the development of a fully functional nervous system.
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Affiliation(s)
- Sofia J Araújo
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain.,Institute of Biomedicine, University of Barcelona (IBUB), Barcelona, Spain
| | - Isao Kuraoka
- Department of Chemistry, Faculty of Science, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan
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Kindil Z, Senhaji MA, Bakhchane A, Charoute H, Chihab S, Nadifi S, Barakat A. Genetic investigation of XPA gene: high frequency of the c.682C>T mutation in Moroccan XP patients with moderate clinical profile. BMC Res Notes 2017; 10:704. [PMID: 29208038 PMCID: PMC5718079 DOI: 10.1186/s13104-017-3042-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 11/30/2017] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVE Xeroderma pigmentosum (XP) is a genetically and clinically heterogeneous disease, associated with an inherited defect in one of eight different genes (XPA to XPG and XPV). In addition to the early onset of the skin manifestations, the XP group A is marked by the presence of a mild to severe neural disorders which appear tardily and worsens with age. In this study, 9 patients with moderate clinical profile belonging to 6 XP families were recruited to determine the XPA mutational spectrum in Morocco, using the direct sequencing of the whole coding region of the XPA gene. RESULTS The genetic investigation of the XPA gene showed that 7 from 9 patients were homozygous for the c.682C>T, p.Arg228X mutation, while all their investigated family members were heterozygous. The frequency of this mutation was estimated to be 83.33% (5/6 families) .The molecular analysis of the 5 other exons of the XPA gene, showed that the 2 negative siblings carried no mutation in the XPA gene. This finding suggests that c.682C>T (p.Arg228X) mutation is relatively associated with moderate phenotype in XP group A Moroccan families; this result will also contribute to improve the molecular diagnosis of XP disease in Moroccan patients.
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Affiliation(s)
- Zineb Kindil
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, 1, Place Louis Pasteur, 20360, Casablanca, Morocco.,Laboratory of Genetics and Molecular Pathology, Faculty of Medicine, Hassan II University, Casablanca, Morocco
| | - Mohamed Amine Senhaji
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, 1, Place Louis Pasteur, 20360, Casablanca, Morocco
| | - Amina Bakhchane
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, 1, Place Louis Pasteur, 20360, Casablanca, Morocco
| | - Hicham Charoute
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, 1, Place Louis Pasteur, 20360, Casablanca, Morocco
| | - Soumia Chihab
- Department of Dermatology, Hospital University Ibn Rochd, Casablanca, Morocco
| | - Sellama Nadifi
- Laboratory of Genetics and Molecular Pathology, Faculty of Medicine, Hassan II University, Casablanca, Morocco
| | - Abdelhamid Barakat
- Human Molecular Genetics Laboratory, Institut Pasteur du Maroc, 1, Place Louis Pasteur, 20360, Casablanca, Morocco.
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Xeroderma pigmentosum: low prevalence of germline XPA mutations in a Brazilian XP population. Int J Mol Sci 2015; 16:8988-96. [PMID: 25913378 PMCID: PMC4425119 DOI: 10.3390/ijms16048988] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 04/14/2015] [Accepted: 04/17/2015] [Indexed: 12/20/2022] Open
Abstract
Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by DNA repair defects that cause photophobia, sunlight-induced cancers, and neurodegeneration. Prevalence of germline mutations in the nucleotide excision repair gene XPA vary significantly in different populations. No Brazilian patients have been reported to carry a germline mutation in this gene. In this study, the germline mutational status of XPA was determined in Brazilian patients exhibiting major clinical features of XP syndrome. The study was conducted on 27 unrelated patients from select Brazilian families. A biallelic inactivating transition mutation c.619C>T (p.Arg207Ter) was identified in only one patient with a history of neurological impairment and mild skin abnormalities. These findings suggest that XP syndrome is rarely associated with inherited disease-causing XPA mutations in the Brazilian population. Additionally, this report demonstrates the effectiveness of genotype-phenotype correlation as a valuable tool to guide direct genetic screening.
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A short review on the implications of base excision repair pathway for neurons: relevance to neurodegenerative diseases. Mitochondrion 2013; 16:38-49. [PMID: 24220222 DOI: 10.1016/j.mito.2013.10.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 10/31/2013] [Accepted: 10/31/2013] [Indexed: 12/13/2022]
Abstract
Oxidative DNA damage results from the attack by reactive oxygen and nitrogen species (ROS/RNS) on human genome. This includes base modifications such as oxidized bases, abasic (AP) sites, and single-strand breaks (SSBs), all of which are repaired by the base excision repair (BER) pathway, one among the six known repair pathways. BER-pathway in mammalian cells involves several evolutionarily conserved proteins and is also linked to genome replication and transcription. The BER-pathway enzymes, namely, DNA glycosylases (DGs) and the end-processing proteins such as abasic endonuclease (APE1), form complexes with downstream repair enzymes via protein-protein and DNA-protein interactions. An emerging concept for BER proteins is their involvement in non-canonical functions associated to RNA metabolism, which is opening new interesting perspectives. Various mechanisms that are underlined in maintaining neuronal cell genome integrity are identified, but are inconclusive in providing protection against oxidative damage in neurodegenerative disorders, main emphasis is given towards the role played by the proteins of BER-pathway that is discussed. In addition, mechanisms of action of BER-pathway in nuclear vs. mitochondria as well as the non-canonical functions are discussed in connection to human neurodegenerative diseases.
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Jiang Y, Guo C, Fishel ML, Wang ZY, Vasko MR, Kelley MR. Role of APE1 in differentiated neuroblastoma SH-SY5Y cells in response to oxidative stress: use of APE1 small molecule inhibitors to delineate APE1 functions. DNA Repair (Amst) 2009; 8:1273-82. [PMID: 19726241 DOI: 10.1016/j.dnarep.2009.08.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 07/20/2009] [Accepted: 08/10/2009] [Indexed: 11/25/2022]
Abstract
Oxidative DNA damage has been implicated in a number of central nervous system pathologies. The base excision repair (BER) pathway is one of the most important cellular protection mechanisms that respond to oxidative DNA damage. Human apurinic (apyrimidinic) endonuclease/redox effector factor (APE1/Ref-1 or APE1) is an essential enzyme in the BER pathway and is expressed in both mitotic and post-mitotic cells in humans. In neurons, a reduction of APE1 expression increases chemotherapy-induced cytotoxicity, while overexpression of APE1 protects cells against the cytotoxicity. However, given the multiple functions of APE1, knockdown of total APE1 is not completely informative of whether it is the redox or DNA repair activity, or interactions with other proteins. Therefore, the use of selective small molecules that can block each function independent of the other is of great benefit in ascertaining APE1 function in post-mitotic cells. In this study, we chose differentiated SH-SY5Y cells as our post-mitotic cell line model to investigate whether a drug-induced decrease in APE1 DNA repair or redox activity contributes to the growth and survival of post-mitotic cells under oxidative DNA damaging conditions. Here, we demonstrate that overexpression of WT-APE1 or C65-APE1 (repair competent) results in significant increase in cell viability after exposure to H(2)O(2). However, the 177/226-APE1 (repair deficient) did not show a protective effect. This phenomenon was further confirmed by the use of methoxyamine (MX), which blocks the repair activity of APE1 that results in enhanced cell killing and apoptosis in differentiated SH-SY5Y cells and in neuronal cultures after oxidative DNA damaging treatments. Blocking APE1 redox function by a small molecule inhibitor, BQP did not decrease viability of SH-SY5Y cells or neuronal cultures following oxidative DNA damaging treatments. Our results demonstrate that the DNA repair function of APE1 contributes to the survival of nondividing post-mitotic cells following oxidative DNA damage.
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Affiliation(s)
- Yanlin Jiang
- Department of Pediatrics (Section of Hematology/Oncology), Herman B Wells Center for Pediatric Research, United States
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Roles of oxidative stress in xeroderma pigmentosum. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 637:120-7. [PMID: 19181117 DOI: 10.1007/978-0-387-09599-8_13] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Tissue damage caused by oxidative stress has been implicated in aging, carcinogenesis, atherosclerosis and neurodegeneration. In xeroderma pigmentosum (XP) and Cockayne syndrome (CS), oxidative stress is associated with promoted occurrence of skin cancers and progressive neurodegeneration, because decreased DNA repair and persistent DNA damage can result in augmented oxidative nucleotide damage. Oxidative nucleotide damage has been investigated mainly in isolated human skin and blood cells or their cell lines, in which CS cells may be more sensitive to oxidative DNA lesions than XP cells. However, cells from patients with XP group A (XPA) show defective repair of 8, 5'-(S)-cyclo-2'-deoxyadenosine, a free radical-induced endogenous DNA lesion and antioxidant system seems to be disturbed variously in cells from XP patients. We have neuropathologically investigated the involvement of oxidative stress in the brains of XPA and CS autopsy cases and clarified the enhanced lipid peroxidation and protein glycation in the pallidal and cerebellar degeneration. Also, oxidative nucleotide damage with reduced expression of superoxide dismutases has been identified in the basal ganglia lesions, lending further weight involvement of oxidative stress in neurodegeneration in XPA patients. Additionally, we are developing ELISA analysis of oxidative stress markers in the urine and cerebrospinal fluid from XP patients, which will aid with further data on oxidative stress in pathogenesis of XP.
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Parenti R, Paratore S, Torrisi A, Cavallaro S. A natural antisense transcript against Rad18, specifically expressed in neurons and upregulated during β-amyloid-induced apoptosis. Eur J Neurosci 2007; 26:2444-57. [DOI: 10.1111/j.1460-9568.2007.05864.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Crowe SL, Movsesyan VA, Jorgensen TJ, Kondratyev A. Rapid phosphorylation of histone H2A.X following ionotropic glutamate receptor activation. Eur J Neurosci 2006; 23:2351-61. [PMID: 16706843 PMCID: PMC1534119 DOI: 10.1111/j.1460-9568.2006.04768.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Excessive activation of ionotropic glutamate receptors increases oxidative stress, contributing to the neuronal death observed following neurological insults such as ischemia and seizures. Post-translational histone modifications may be key mediators in the detection and repair of damage resulting from oxidative stress, including DNA damage, and may thus affect neuronal survival in the aftermath of insults characterized by excessive glutamate release. In non-neuronal cells, phosphorylation of histone variant H2A.X (termed gamma-H2AX) occurs rapidly following DNA double-strand breaks. We investigated gamma-H2AX formation in rat cortical neurons (days in vitro 14) following activation of N-methyl-D-aspartate (NMDA) or alpha-amino-3-hydroxyl-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate glutamate receptors using fluorescent immunohistochemical techniques. Moreover, we evaluated the co-localization of gamma-H2AX 'foci' with Mre11, a double-strand break repair protein, to provide further evidence for the activation of this DNA damage response pathway. Here we show that minimally cytotoxic stimulation of ionotropic glutamate receptors was sufficient to evoke gamma-H2AX in neurons, and that NMDA-induced gamma-H2AX foci formation was attenuated by pretreatment with the antioxidant, Vitamin E, and the intracellular calcium chelator, BAPTA-AM. Moreover, a subset of gamma-H2AX foci co-localized with Mre11, indicating that at least a portion of gamma-H2AX foci is damage dependent. The extent of gamma-H2AX induction following glutamate receptor activation corresponded to the increases we observed following conventional DNA damaging agents [i.e. non-lethal doses of gamma-radiation (1 Gy) and hydrogen peroxide (10 microm)]. These data suggest that insults not necessarily resulting in neuronal death induce the DNA damage-evoked chromatin modification, gamma-H2AX, and implicate a role for histone alterations in determining neuronal vulnerability following neurological insults.
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MESH Headings
- 2-Amino-5-phosphonovalerate/pharmacology
- Animals
- Animals, Newborn
- Cell Survival/drug effects
- Cerebral Cortex/cytology
- DNA Repair Enzymes
- DNA-Binding Proteins/metabolism
- Dizocilpine Maleate/pharmacology
- Dose-Response Relationship, Drug
- Dose-Response Relationship, Radiation
- Drug Interactions
- Fluorescent Antibody Technique/methods
- Gamma Rays
- Gene Expression/drug effects
- Gene Expression/radiation effects
- Histones/metabolism
- Hydrogen Peroxide/pharmacology
- MRE11 Homologue Protein
- N-Methylaspartate/pharmacology
- Neurons/drug effects
- Neurons/physiology
- Neurons/radiation effects
- Phosphorylation/drug effects
- Phosphorylation/radiation effects
- Rats
- Rats, Sprague-Dawley
- Receptors, AMPA/agonists
- Receptors, AMPA/antagonists & inhibitors
- Receptors, AMPA/physiology
- Receptors, N-Methyl-D-Aspartate/agonists
- Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors
- Receptors, N-Methyl-D-Aspartate/physiology
- alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/pharmacology
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Affiliation(s)
- Samantha L. Crowe
- Interdisciplinary Program in Neuroscience Georgetown University, Washington, D.C., USA
- Departments of Pharmacology Georgetown University, Washington, D.C., USA
| | - Vilen A. Movsesyan
- Departments of Neuroscience, Georgetown University, Washington, D.C., USA
| | | | - Alexei Kondratyev
- Departments of Pharmacology Georgetown University, Washington, D.C., USA
- Departments of Pediatrics, Georgetown University, Washington, D.C., USA
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Englander EW, Ma H. Differential modulation of base excision repair activities during brain ontogeny: implications for repair of transcribed DNA. Mech Ageing Dev 2005; 127:64-9. [PMID: 16257035 DOI: 10.1016/j.mad.2005.09.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Revised: 09/20/2005] [Accepted: 09/20/2005] [Indexed: 11/17/2022]
Abstract
DNA repair sustains fidelity of genomic replication in proliferating cells and integrity of transcribed sequences in postmitotic tissues. The repair process is critical in the brain, because high oxygen consumption exacerbates the risk for accumulation of oxidative DNA lesions in postmitotic neurons. Most oxidative DNA damage is repaired by the base excision repair (BER) pathway, which is initiated by specialized DNA glycosylases. Because the newly discovered Nei-like mammalian DNA glycosylases (NEIL1/2) proficiently excise oxidized bases from bubble structured DNA, it was suggested that NEILs favor repair of transcribed or replicated DNA. In addition, since NEILs generate 3'-phosphate termini, which are poor targets for AP endonuclease (APE1), it was proposed that APE1-dependent and independent BER sub-pathways exist in mammalian cells. We measured expression and activities of BER enzymes during brain ontogeny, i.e., during a physiologic transition from proliferative to postmitotic differentiated state. While a subset of BER enzymes, exhibited declining expression and excision activities, expression of NEIL1 and NEIL2 glycosylases increased during brain development. Furthermore, the capacity for excision of 5-hydroxyuracil from bubble structured DNA was retained in the mature rat brain suggesting a role for NEIL glycosylases in maintaining the integrity of transcribed DNA in postmitotic brain.
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Affiliation(s)
- Ella W Englander
- Department of Surgery, The University of Texas Medical Branch, Shriners Hospitals for Children, 815 Market Street, Galveston, TX 77550, USA.
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Bignold LP. The cell-type-specificity of inherited predispositions to tumours: review and hypothesis. Cancer Lett 2005; 216:127-46. [PMID: 15533589 DOI: 10.1016/j.canlet.2004.07.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Revised: 07/28/2004] [Accepted: 07/29/2004] [Indexed: 12/19/2022]
Abstract
Most hereditary predispositions to tumours affect only one particular cell type of the body but the genes bearing the relevant germ-line mutation are not cell-type-specific. Some predisposition syndromes include increased risks of lesions (developmental or tumourous) of unrelated cell types, in any individual predisposed to the main lesion (e.g. osteosarcoma in patients predisposed to retinoblastoma). Other predispositions to additional lesions occur only in members of some families with the predisposition to the basic lesion (e.g. Gardner's syndrome in some families suffering familial adenomatous polyposis). In yet other predisposition syndromes, different mutations of the same gene are associated with markedly differing family-specific clinical syndromes. In particular, identical germline mutations (e.g. in APC, RET and PTEN genes), have been found associated with differing clinical syndromes in different families. This paper reviews previously suggested mechanisms of the cell-type specificity of inherited predispositions to tumour. Models of tumour formation in predisposition syndromes are discussed, especially those involving a germline mutation (the first 'hit') of a tumour suppressor gene (TSG) and a second (somatic) hit on the second allele of the same TSG. A modified model is suggested, such that the second hit is a co-mutation of the second allele of the TSG and a regulator which is specific for growth and/or differentiation of the cell type which is susceptible to the tumour predisposition. In some cases of tumour, the second hit may be large enough to be associated with a cytogenetically-demonstrable abnormality of the part of the chromosome carrying the TSG, but in other cases, the co-mutation may be of 'sub-cytogenetic' size (i.e. 10(2)-10(5) bases). For the latter, mutational mechanisms of frameshift and impaired fidelity of replication of DNA by DNA polyerases may sometimes be involved. Candidate cell-type-specific regulators may include microRNAs and perhaps transcription factors. It is suggested that searching the introns within 10(5)-10(6) bases either side of known of exonic mutations of TSGs associated with inherited tumour predisposition might reveal microRNA cell-type-specific regulators. Additional investigations may involve fluorescent in situ hybridisations on interphase tumour nuclei.
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Affiliation(s)
- Leon P Bignold
- Division of Tissue Pathology, Institute of Medical and Veterinary Science, PO Box 14, Rundle Mall, Adelaide, SA 5001, Australia.
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Lee HM, Hu Z, Ma H, Greeley GH, Wang C, Englander EW. Developmental changes in expression and subcellular localization of the DNA repair glycosylase, MYH, in the rat brain. J Neurochem 2004; 88:394-400. [PMID: 14690527 DOI: 10.1046/j.1471-4159.2003.02164.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mammalian cells employ a network of DNA repair pathways. DNA repair is required during development to ensure accuracy of DNA replication in the rapidly dividing embryonic cells and to maintain genomic integrity in the mature organism. An enzyme involved in repair of replication errors generated on either normal or oxidatively damaged DNA templates, is the mammalian ortholog of the Escherichia coli MutY DNA glycosylase (MYH). We show that levels of MYH isoform, detected at the E14 embryonic stage, decrease during embryonic and neonatal rat development, while new isoforms appear and gradually increase in the neonate and adult brain. The temporally declining expression of embryonic MYH resembles the pattern of proliferating cell nuclear antigen (PCNA) decline during this period. Immunohistochemical analyses of the embryonic brain show that cells staining for MYH initially coincide with cells staining for PCNA. At later stages PCNA declines, while MYH is detected primarily outside the nucleus. MutY-like glycosylase activity for adenines misincorporated opposite oxidized guanines is detected in both, embryonic and adult brain extracts. Together, these findings suggest that in proliferating embryonic cells, MYH might be primarily involved in post replicative repair of nuclear DNA, whereas in post mitotic neurons, in the repair of mitochondrial DNA.
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Affiliation(s)
- Heung-Man Lee
- Department of Surgery, The University of Texas Medical Branch, Galveston, Texas, USA
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Karahalil B, Hogue BA, de Souza-Pinto NC, Bohr VA. Base excision repair capacity in mitochondria and nuclei: tissue-specific variations. FASEB J 2002; 16:1895-902. [PMID: 12468454 DOI: 10.1096/fj.02-0463com] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Base excision repair is the main pathway for repair of oxidative base lesions in DNA. Mammalian cells must maintain genomic stability in their nuclear and mitochondrial genomes, which have different degrees of vulnerability to DNA damage. This study quantifies DNA glycosylase activity in mitochondria and nucleus from C57/BL 6 mouse tissues including brain, liver, heart, muscle, kidney, and testis. The activities of oxoguanine DNA glycosylase (OGG1), uracil DNA glycosylase, and endonuclease III homologue 1 (NTH1) were measured using oligonucleotide substrates with DNA lesions specific for each glycosylase. Mitochondrial content was normalized to citrate synthase activity and mitochondrial function was assessed by measuring cytochrome c oxidase (COX) activity. In nuclear and mitochondrial extracts, the highest DNA glycosylase activities were in testis. Brain and heart, tissues with the highest oxidative load, did not have higher levels of OGG1 or NTH1 activity than muscle or kidney, which are more glycolytic tissues. In general, mitochondrial extracts have lower DNA glycosylase activity than nuclear extracts. There was no correlation between glycosylase activities in the mitochondrial extracts and COX activity, suggesting that DNA repair enzymes may be regulated by a mechanism different from this mitochondrial enzyme.
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Affiliation(s)
- Bensu Karahalil
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
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