1
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Krasikova YS, Lavrik OI, Rechkunova NI. The XPA Protein-Life under Precise Control. Cells 2022; 11:cells11233723. [PMID: 36496984 PMCID: PMC9739396 DOI: 10.3390/cells11233723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 11/24/2022] Open
Abstract
Nucleotide excision repair (NER) is a central DNA repair pathway responsible for removing a wide variety of DNA-distorting lesions from the genome. The highly choreographed cascade of core NER reactions requires more than 30 polypeptides. The xeroderma pigmentosum group A (XPA) protein plays an essential role in the NER process. XPA interacts with almost all NER participants and organizes the correct NER repair complex. In the absence of XPA's scaffolding function, no repair process occurs. In this review, we briefly summarize our current knowledge about the XPA protein structure and analyze the formation of contact with its protein partners during NER complex assembling. We focus on different ways of regulation of the XPA protein's activity and expression and pay special attention to the network of post-translational modifications. We also discuss the data that is not in line with the currently accepted hypothesis about the functioning of the XPA protein.
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Affiliation(s)
- Yuliya S. Krasikova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Olga I. Lavrik
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk 630090, Russia
| | - Nadejda I. Rechkunova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia
- Correspondence:
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2
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Zhang X, Yin M, Hu J. Nucleotide excision repair: a versatile and smart toolkit. Acta Biochim Biophys Sin (Shanghai) 2022; 54:807-819. [PMID: 35975604 PMCID: PMC9828404 DOI: 10.3724/abbs.2022054] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Nucleotide excision repair (NER) is a major pathway to deal with bulky adducts induced by various environmental toxins in all cellular organisms. The two sub-pathways of NER, global genome repair (GGR) and transcription-coupled repair (TCR), differ in the damage recognition modes. In this review, we describe the molecular mechanism of NER in mammalian cells, especially the details of damage recognition steps in both sub-pathways. We also introduce new sequencing methods for genome-wide mapping of NER, as well as recent advances about NER in chromatin by these methods. Finally, the roles of NER factors in repairing oxidative damages and resolving R-loops are discussed.
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Affiliation(s)
| | | | - Jinchuan Hu
- Correspondence address. Tel: +86-21-54237702; E-mail:
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3
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Kim SH, Kim GH, Kemp MG, Choi JH. TREX1 degrades the 3' end of the small DNA oligonucleotide products of nucleotide excision repair in human cells. Nucleic Acids Res 2022; 50:3974-3984. [PMID: 35357486 PMCID: PMC9023299 DOI: 10.1093/nar/gkac214] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 03/02/2022] [Accepted: 03/18/2022] [Indexed: 01/01/2023] Open
Abstract
The nucleotide excision repair (NER) machinery removes UV photoproducts from DNA in the form of small, excised damage-containing DNA oligonucleotides (sedDNAs) ∼30 nt in length. How cells process and degrade these byproducts of DNA repair is not known. Using a small scale RNA interference screen in UV-irradiated human cells, we identified TREX1 as a major regulator of sedDNA abundance. Knockdown of TREX1 increased the level of sedDNAs containing the two major UV photoproducts and their association with the NER proteins TFIIH and RPA. Overexpression of wild-type but not nuclease-inactive TREX1 significantly diminished sedDNA levels, and studies with purified recombinant TREX1 showed that the enzyme efficiently degrades DNA located 3′ of the UV photoproduct in the sedDNA. Knockdown or overexpression of TREX1 did not impact the overall rate of UV photoproduct removal from genomic DNA or cell survival, which indicates that TREX1 function in sedDNA degradation does not impact NER efficiency. Taken together, these results indicate a previously unknown role for TREX1 in promoting the degradation of the sedDNA products of the repair reaction. Because TREX1 mutations and inefficient DNA degradation impact inflammatory and immune signaling pathways, the regulation of sedDNA degradation by TREX1 may contribute to photosensitive skin disorders.
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Affiliation(s)
- Seon Hee Kim
- Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon 305-340, Republic of Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-340, Republic of Korea
| | - Geun Hoe Kim
- Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon 305-340, Republic of Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-340, Republic of Korea
| | - Michael G Kemp
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, OH 45435, USA.,Dayton Veterans Administration Medical Center, Dayton, OH 45428, USA
| | - Jun-Hyuk Choi
- Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon 305-340, Republic of Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-340, Republic of Korea
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4
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Andrade MJ, Van Lonkhuyzen DR, Upton Z, Satyamoorthy K. RPA facilitates rescue of keratinocytes from UVB radiation damage through insulin-like growth factor-I signalling. J Cell Sci 2021; 134:jcs255786. [PMID: 34137442 DOI: 10.1242/jcs.255786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 05/10/2021] [Indexed: 01/19/2023] Open
Abstract
UVBR-induced photolesions in genomic DNA of keratinocytes impair cellular functions and potentially determine the cell fate post-irradiation. The ability of insulin-like growth factor-I (IGF-I) to rescue epidermal keratinocytes after photodamage via apoptosis prevention and photolesion removal was recently demonstrated using in vitro two-dimensional and three-dimensional skin models. Given the limited knowledge of specific signalling cascades contributing to post-UVBR IGF-I effects, we used inhibitors to investigate the impact of blockade of various signalling mediators on IGF-I photoprotection. IGF-I treatment, in the presence of signalling inhibitors, particularly TDRL-505, which targets replication protein A (RPA), impaired activation of IGF-1R downstream signalling, diminished cyclobutane pyrimidine dimer removal, arrested growth, reduced cell survival and increased apoptosis. Further, the transient partial knockdown of RPA was found to abrogate IGF-I-mediated responses in keratinocytes, ultimately affecting photoprotection and, thereby, establishing that RPA is required for IGF-I function. Our findings thus elucidate the importance of RPA in linking the damage response activation, cell cycle regulation, repair and survival pathways, separately initiated by IGF-I upon UVBR-induced damage. This information is potentially imperative for the development of effective sunburn and photodamage repair strategies. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Melisa J Andrade
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
- Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland 4059, Australia
| | - Derek R Van Lonkhuyzen
- Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland 4059, Australia
| | - Zee Upton
- Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland 4059, Australia
- Skin Research Institute of Singapore, Agency for Science, Technology and Research, Singapore138648
| | - Kapaettu Satyamoorthy
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
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5
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Rechkunova NI, Krasikova YS, Lavrik OI. Interactome of Base and Nucleotide Excision DNA Repair Systems. Mol Biol 2021. [DOI: 10.1134/s0026893321020126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Choi JH, Han S, Kemp MG. Detection of the small oligonucleotide products of nucleotide excision repair in UVB-irradiated human skin. DNA Repair (Amst) 2019; 86:102766. [PMID: 31838380 DOI: 10.1016/j.dnarep.2019.102766] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/26/2019] [Accepted: 12/04/2019] [Indexed: 11/29/2022]
Abstract
UVB radiation results in the formation of potentially mutagenic photoproducts in the DNA of epidermal skin cells. In vitro approaches have demonstrated that the nucleotide excision repair (NER) machinery removes UV photoproducts from DNA in the form of small (∼30-nt-long), excised, damage-containing DNA oligonucleotides (sedDNAs). Though this process presumably takes place in human skin exposed to UVB radiation, sedDNAs have not previously been detected in human skin. Using surgically discarded human skin, we have optimized the detection of the sedDNA products of NER from small amounts of human epidermal tissue ex vivo within minutes of UVB exposure and after UVB doses that normally lead to minimal erythema. Moreover, sedDNA generation was inhibited by treatment of skin explants with spironolactone, which depletes the epidermis of the essential NER protein XPB to mimic the skin of xeroderma pigmentosum patients. Time course experiments revealed that a partially degraded form of the sedDNAs could be readily detected even 12 hours following UVB exposure, which indicates that these repair products are relatively stable in human skin epidermis. Together, these data suggest that sedDNA detection may be a useful assay for determining how genetic, environmental, and other factors influence NER activity in human skin epidermis and whether abnormal sedDNA processing contributes to photosensitive skin disorders.
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Affiliation(s)
- Jun-Hyuk Choi
- Center for Bioanalysis, Korea Research Institute of Standards and Science, Republic of Korea; Department of Bio-Analytical Science, University of Science & Technology, Republic of Korea
| | - Sueji Han
- Center for Bioanalysis, Korea Research Institute of Standards and Science, Republic of Korea; Department of Bio-Analytical Science, University of Science & Technology, Republic of Korea
| | - Michael G Kemp
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, OH 45435, United States.
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7
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Rechkunova NI, Maltseva EA, Lavrik OI. Post-translational Modifications of Nucleotide Excision Repair Proteins and Their Role in the DNA Repair. BIOCHEMISTRY (MOSCOW) 2019; 84:1008-1020. [PMID: 31693460 DOI: 10.1134/s0006297919090037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Nucleotide excision repair (NER) is one of the major DNA repair pathways aimed at maintaining genome stability. Correction of DNA damage by the NER system is a multistage process that proceeds with the formation of multiple DNA-protein and protein-protein intermediate complexes and requires precise coordination and regulation. NER proteins undergo post-translational modifications, such as ubiquitination, sumoylation, phosphorylation, acetylation, and poly(ADP-ribosyl)ation. These modifications affect the interaction of NER factors with DNA and other proteins and thus regulate either their recruitment into the complexes or dissociation from these complexes at certain stages of DNA repair, as well as modulate the functional activity of NER proteins and control the process of DNA repair in general. Here, we review the data on the post-translational modifications of NER factors and their effects on DNA repair. Protein poly(ADP-ribosyl)ation catalyzed by poly(ADP-ribose) polymerase 1 and its impact on NER are discussed in detail, since such analysis has not been done before.
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Affiliation(s)
- N I Rechkunova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia. .,Novosibirsk State University, Novosibirsk, 630090, Russia
| | - E A Maltseva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
| | - O I Lavrik
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.,Novosibirsk State University, Novosibirsk, 630090, Russia
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8
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Abstract
The nucleotide excision repair (NER) system removes a variety of types of helix-distorting lesions from DNA through a dual incision mechanism, in which the damaged nucleotide bases are excised in the form of a small, excised, damage-containing single-stranded DNA oligonucleotide (sedDNA). Damage removal leaves a gap in the DNA template that must then be filled in by the action of a DNA polymerase and ligated to the downstream phosphodiester backbone in the DNA to complete the repair reaction. Defects in damage removal, sedDNA processing, or gap filling have the potential to be mutagenic and lethal to cells, and thus several human pathologies, including cancer and aging, are associated with defects in NER. This review summarizes our current understanding of NER with a focus on the enzymes that excise sedDNAs and restore the duplex DNA to its native state in human cells.
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Affiliation(s)
- Michael G Kemp
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, OH, United States.
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9
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Khan AQ, Travers JB, Kemp MG. Roles of UVA radiation and DNA damage responses in melanoma pathogenesis. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2018; 59:438-460. [PMID: 29466611 PMCID: PMC6031472 DOI: 10.1002/em.22176] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/18/2018] [Accepted: 01/22/2018] [Indexed: 05/10/2023]
Abstract
The growing incidence of melanoma is a serious public health issue that merits a thorough understanding of potential causative risk factors, which includes exposure to ultraviolet radiation (UVR). Though UVR has been classified as a complete carcinogen and has long been recognized for its ability to damage genomic DNA through both direct and indirect means, the precise mechanisms by which the UVA and UVB components of UVR contribute to the pathogenesis of melanoma have not been clearly defined. In this review, we therefore highlight recent studies that have addressed roles for UVA radiation in the generation of DNA damage and in modulating the subsequent cellular responses to DNA damage in melanocytes, which are the cell type that gives rise to melanoma. Recent research suggests that UVA not only contributes to the direct formation of DNA lesions but also impairs the removal of UV photoproducts from genomic DNA through oxidation and damage to DNA repair proteins. Moreover, the melanocyte microenvironment within the epidermis of the skin is also expected to impact melanomagenesis, and we therefore discuss several paracrine signaling pathways that have been shown to impact the DNA damage response in UV-irradiated melanocytes. Lastly, we examine how alterations to the immune microenvironment by UVA-associated DNA damage responses may contribute to melanoma development. Thus, there appear to be multiple avenues by which UVA may elevate the risk of melanoma. Protective strategies against excess exposure to UVA wavelengths of light therefore have the potential to decrease the incidence of melanoma. Environ. Mol. Mutagen. 59:438-460, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Aiman Q Khan
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, Ohio
| | - Jeffrey B Travers
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, Ohio
- Dayton Veterans Affairs Medical Center, Dayton, Ohio
| | - Michael G Kemp
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, Ohio
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10
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Simultaneous detection of nucleotide excision repair events and apoptosis-induced DNA fragmentation in genotoxin-treated cells. Sci Rep 2018; 8:2265. [PMID: 29396432 PMCID: PMC5797224 DOI: 10.1038/s41598-018-20527-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/18/2018] [Indexed: 01/27/2023] Open
Abstract
Novel in vivo excision assays for monitoring the excised oligonucleotide products of nucleotide excision repair in UV-irradiated cells have provided unprecedented views of the kinetics and genomic distribution of repair events. However, an unresolved issue is the fate of the excised oligonucleotide products of repair and their mechanism of degradation. Based on our observation that decreases in excised oligonucleotide abundance coincide with the induction of apoptotic signaling in UV-irradiated cells, we considered the possibility that caspase-mediated apoptotic signaling contributes to excised oligonucleotide degradation or to a general inhibition of the excision repair system. However, genetic and pharmacological approaches to inhibit apoptotic signaling demonstrated that caspase-mediated apoptotic signaling does not affect excision repair or excised oligonucleotide stability. Nonetheless, our assay for detecting soluble DNAs produced by repair also revealed the production of larger DNAs following DNA damage induction that was dependent on caspase activation. We therefore further exploited the versatility of this assay by showing that soluble DNAs produced by both nucleotide excision repair and apoptotic signaling can be monitored simultaneously with a diverse set of DNA damaging agents. Thus, our in vivo excision repair assay provides a sensitive measure of both repair kinetics and apoptotic signaling in genotoxin-treated cells.
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11
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Krasikova YS, Rechkunova NI, Maltseva EA, Lavrik OI. RPA and XPA interaction with DNA structures mimicking intermediates of the late stages in nucleotide excision repair. PLoS One 2018; 13:e0190782. [PMID: 29320546 PMCID: PMC5761895 DOI: 10.1371/journal.pone.0190782] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 12/20/2017] [Indexed: 12/26/2022] Open
Abstract
Replication protein A (RPA) and the xeroderma pigmentosum group A (XPA) protein are indispensable for both pathways of nucleotide excision repair (NER). Here we analyze the interaction of RPA and XPA with DNA containing a flap and different size gaps that imitate intermediates of the late NER stages. Using gel mobility shift assays, we found that RPA affinity for DNA decreased when DNA contained both extended gap and similar sized flap in comparison with gapped-DNA structure. Moreover, crosslinking experiments with the flap-gap DNA revealed that RPA interacts mainly with the ssDNA platform within the long gap and contacts flap in DNA with a short gap. XPA exhibits higher affinity for bubble-DNA structures than to flap-gap-containing DNA. Protein titration analysis showed that formation of the RPA-XPA-DNA ternary complex depends on the protein concentration ratio and these proteins can function as independent players or in tandem. Using fluorescently-labelled RPA, direct interaction of this protein with XPA was detected and characterized quantitatively. The data obtained allow us to suggest that XPA can be involved in the post-incision NER stages via its interaction with RPA.
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Affiliation(s)
| | - Nadejda I. Rechkunova
- Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | | | - Olga I. Lavrik
- Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
- * E-mail:
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12
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Chiou YY, Hu J, Sancar A, Selby CP. RNA polymerase II is released from the DNA template during transcription-coupled repair in mammalian cells. J Biol Chem 2017; 293:2476-2486. [PMID: 29282293 DOI: 10.1074/jbc.ra117.000971] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 12/19/2017] [Indexed: 11/06/2022] Open
Abstract
In mammalian cells, bulky DNA adducts located in the template but not the coding strand of genes block elongation by RNA polymerase II (RNAPII). The blocked RNAPII targets these transcription-blocking adducts to undergo more rapid excision repair than adducts located elsewhere in the genome. In excision repair, coupled incisions are made in the damaged DNA strand on both sides of the adduct. The fate of RNAPII in the course of this transcription-coupled repair (TCR) pathway is unclear. To address the fate of RNAPII, we used methods that control transcription to initiate a discrete "wave" of elongation complexes. Analyzing genome-wide transcription and repair by next-generation sequencing, we identified locations of elongation complexes and transcription-repair coupling events in genes throughout the genome. Using UV-exposed human skin fibroblasts, we found that, at the dose used, a single wave of elongation complexes was blocked within the first 25 kb of genes. TCR occurred where the elongation complexes were blocked, and repair was associated with the dissociation of these complexes. These results indicate that individual elongation complexes do not engage in multiple rounds of TCR with successive lesions. Our results are consistent with a model in which RNAPII is dissociated after the dual incision of the transcription-blocking lesion, perhaps by Cockayne syndrome group B translocase, or during the synthesis of a repair patch.
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Affiliation(s)
- Yi-Ying Chiou
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and.,the Institute of Biochemistry, National Chung Hsing University, Taichung 402, Taiwan
| | - Jinchuan Hu
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and
| | - Aziz Sancar
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and
| | - Christopher P Selby
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and
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13
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Impact of Age and Insulin-Like Growth Factor-1 on DNA Damage Responses in UV-Irradiated Human Skin. Molecules 2017; 22:molecules22030356. [PMID: 28245638 PMCID: PMC5432641 DOI: 10.3390/molecules22030356] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 02/22/2017] [Accepted: 02/24/2017] [Indexed: 01/19/2023] Open
Abstract
The growing incidence of non-melanoma skin cancer (NMSC) necessitates a thorough understanding of its primary risk factors, which include exposure to ultraviolet (UV) wavelengths of sunlight and age. Whereas UV radiation (UVR) has long been known to generate photoproducts in genomic DNA that promote genetic mutations that drive skin carcinogenesis, the mechanism by which age contributes to disease pathogenesis is less understood and has not been sufficiently studied. In this review, we highlight studies that have considered age as a variable in examining DNA damage responses in UV-irradiated skin and then discuss emerging evidence that the reduced production of insulin-like growth factor-1 (IGF-1) by senescent fibroblasts in the dermis of geriatric skin creates an environment that negatively impacts how epidermal keratinocytes respond to UVR-induced DNA damage. In particular, recent data suggest that two principle components of the cellular response to DNA damage, including nucleotide excision repair and DNA damage checkpoint signaling, are both partially defective in keratinocytes with inactive IGF-1 receptors. Overcoming these tumor-promoting conditions in aged skin may therefore provide a way to lower aging-associated skin cancer risk, and thus we will consider how dermal wounding and related clinical interventions may work to rejuvenate the skin, re-activate IGF-1 signaling, and prevent the initiation of NMSC.
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14
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Musich PR, Li Z, Zou Y. Xeroderma Pigmentosa Group A (XPA), Nucleotide Excision Repair and Regulation by ATR in Response to Ultraviolet Irradiation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 996:41-54. [PMID: 29124689 DOI: 10.1007/978-3-319-56017-5_4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The sensitivity of Xeroderma pigmentosa (XP) patients to sunlight has spurred the discovery and genetic and biochemical analysis of the eight XP gene products (XPA-XPG plus XPV) responsible for this disorder. These studies also have served to elucidate the nucleotide excision repair (NER) process, especially the critical role played by the XPA protein. More recent studies have shown that NER also involves numerous other proteins normally employed in DNA metabolism and cell cycle regulation. Central among these is ataxia telangiectasia and Rad3-related (ATR), a protein kinase involved in intracellular signaling in response to DNA damage, especially DNA damage-induced replicative stresses. This review summarizes recent findings on the interplay between ATR as a DNA damage signaling kinase and as a novel ligand for intrinsic cell death proteins to delay damage-induced apoptosis, and on ATR's regulation of XPA and the NER process for repair of UV-induced DNA adducts. ATR's regulatory role in the cytosolic-to-nuclear translocation of XPA will be discussed. In addition, recent findings elucidating a non-NER role for XPA in DNA metabolism and genome stabilization at ds-ssDNA junctions, as exemplified in prematurely aging progeroid cells, also will be reviewed.
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Affiliation(s)
- Phillip R Musich
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, 37614, USA
| | - Zhengke Li
- Department of Cancer Genetics and Epigenetics, City of Hope Comprehensive Cancer Center, 1500 E Duarte Rd, Duarte, CA, 91007, USA
| | - Yue Zou
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, 37614, USA.
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15
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Fouquerel E, Opresko P. Convergence of The Nobel Fields of Telomere Biology and DNA Repair. Photochem Photobiol 2017; 93:229-237. [PMID: 27861975 PMCID: PMC5315637 DOI: 10.1111/php.12672] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/26/2016] [Indexed: 02/02/2023]
Abstract
The fields of telomere biology and DNA repair have enjoyed a great deal of cross-fertilization and convergence in recent years. Telomeres function at chromosome ends to prevent them from being falsely recognized as chromosome breaks by the DNA damage response and repair machineries. Conversely, both canonical and nonconical functions of numerous DNA repair proteins have been found to be critical for preserving telomere structure and function. In 2009, Elizabeth Blackburn, Carol Greider and Jack Szostak were awarded the Nobel prize in Physiology or Medicine for the discovery of telomeres and telomerase. Four years later, pioneers in the field of DNA repair, Aziz Sancar, Tomas Lindahl and Paul Modrich were recognized for their seminal contributions by being awarded the Nobel Prize in Chemistry. This review is part of a special issue meant to celebrate this amazing achievement, and will focus in particular on the convergence of nucleotide excision repair and telomere biology, and will discuss the profound implications for human health.
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Affiliation(s)
- Elise Fouquerel
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health, University of Pittsburgh Cancer Institute Research Pavilion, 5117 Centre Avenue, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Patricia Opresko
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health, University of Pittsburgh Cancer Institute Research Pavilion, 5117 Centre Avenue, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
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16
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Kemp MG, Spandau DF, Simman R, Travers JB. Insulin-like Growth Factor 1 Receptor Signaling Is Required for Optimal ATR-CHK1 Kinase Signaling in Ultraviolet B (UVB)-irradiated Human Keratinocytes. J Biol Chem 2016; 292:1231-1239. [PMID: 27979966 DOI: 10.1074/jbc.m116.765883] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 12/08/2016] [Indexed: 01/16/2023] Open
Abstract
UVB wavelengths of light induce the formation of photoproducts in DNA that are potentially mutagenic if not properly removed by the nucleotide excision repair machinery. As an additional mechanism to minimize the risk of mutagenesis, UVB-irradiated cells also activate a checkpoint signaling cascade mediated by the ATM and Rad3-related (ATR) and checkpoint kinase 1 (CHK1) kinases to transiently suppress DNA synthesis and cell cycle progression. Given that keratinocytes in geriatric skin display reduced activation of the insulin-like growth factor 1 receptor (IGF-1R) and alterations in DNA repair rate, apoptosis, and senescence following UVB exposure, here we used cultured human keratinocytes in vitro and skin explants ex vivo to examine how IGF-1R activation status affects ATR-CHK1 kinase signaling and the inhibition of DNA replication following UVB irradiation. We find that disruption of IGF-1R signaling with small-molecule inhibitors or IGF-1 withdrawal partially abrogates both the phosphorylation and activation of CHK1 by ATR and the accompanying inhibition of chromosomal DNA synthesis in UVB-irradiated keratinocytes. A critical protein factor that mediates both ATR-CHK1 signaling and nucleotide excision repair is replication protein A, and we find that its accumulation on UVB-damaged chromatin is partially attenuated in cells with an inactive IGF-1R. These results indicate that mutagenesis and skin carcinogenesis in IGF-1-deficient geriatric skin may be caused by defects in multiple cellular responses to UVB-induced DNA damage, including through a failure to properly suppress DNA synthesis on UVB-damaged DNA templates.
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Affiliation(s)
- Michael G Kemp
- From the Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, Ohio 45435,
| | - Dan F Spandau
- the Departments of Dermatology and.,Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, and
| | - Richard Simman
- From the Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, Ohio 45435
| | - Jeffrey B Travers
- From the Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, Ohio 45435.,the Dayton Veterans Affairs Medical Center, Dayton, Ohio 45428
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17
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Song J, Kemp MG, Choi JH. Detection of the Excised, Damage-containing Oligonucleotide Products of Nucleotide Excision Repair in Human Cells. Photochem Photobiol 2016; 93:192-198. [PMID: 27634428 PMCID: PMC5315615 DOI: 10.1111/php.12638] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 08/10/2016] [Indexed: 11/29/2022]
Abstract
The human nucleotide excision repair system targets a wide variety of DNA adducts for removal from DNA, including photoproducts induced by UV wavelengths of sunlight. A key feature of nucleotide excision repair is its dual incision mechanism, which results in generation of a small, damage‐containing oligonucleotide approximately 24 to 32 nt in length. Detection of these excised oligonucleotides using cell‐free extracts and purified proteins with defined DNA substrates has provided a robust biochemical assay for excision repair activity in vitro. However, the relevance of a number of in vitro findings to excision repair in living cells in vivo has remained unresolved. Over the past few years, novel methods for detecting and isolating the excised oligonucleotide products of repair in vivo have therefore been developed. Here we provide a basic outline of a sensitive and versatile in vivo excision assay and discuss how the assay both confirms previous in vitro findings and offers a number of advantages over existing cell‐based DNA repair assays. Thus, the in vivo excision assay offers a powerful tool for readily monitoring the repair of DNA lesions induced by a large number of environmental carcinogens and anticancer compounds.
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Affiliation(s)
- Jimyeong Song
- Center for Bioanalysis, Korea Research Institute of Standards and Science, Daejeon, Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon, Korea
| | - Michael G Kemp
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, OH
| | - Jun-Hyuk Choi
- Center for Bioanalysis, Korea Research Institute of Standards and Science, Daejeon, Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon, Korea
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18
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Kemp MG, Hu J. PostExcision Events in Human Nucleotide Excision Repair. Photochem Photobiol 2016; 93:178-191. [PMID: 27645806 DOI: 10.1111/php.12641] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 08/26/2016] [Indexed: 12/27/2022]
Abstract
The nucleotide excision repair system removes a wide variety of DNA lesions from the human genome, including photoproducts induced by ultraviolet (UV) wavelengths of sunlight. A defining feature of nucleotide excision repair is its dual incision mechanism, in which two nucleolytic incision events on the damaged strand of DNA at sites bracketing the lesion generate a damage-containing DNA oligonucleotide and a single-stranded DNA gap approximately 30 nucleotides in length. Although the early events of nucleotide excision repair, which include lesion recognition and the dual incisions, have been explored in detail and are reasonably well understood, the fate of the single-stranded DNA gaps and excised oligonucleotide products of repair have not been as extensively examined. In this review, recent findings that address these less-explored aspects of nucleotide excision repair are discussed and support the concept that postincision gap and excised oligonucleotide processing are critical steps in the cellular response to DNA damage induced by UV light and other environmental carcinogens. Defects in these latter stages of repair lead to cell death and other DNA damage signaling responses and may therefore contribute to a number of human disease states associated with exposure to UV wavelengths of sunlight, including skin cancer, aging and autoimmunity.
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Affiliation(s)
- Michael G Kemp
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, OH
| | - Jinchuan Hu
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, NC
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19
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Sancar A. Mechanisms of DNA Repair by Photolyase and Excision Nuclease (Nobel Lecture). Angew Chem Int Ed Engl 2016; 55:8502-27. [PMID: 27337655 DOI: 10.1002/anie.201601524] [Citation(s) in RCA: 174] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Indexed: 01/27/2023]
Abstract
Ultraviolet light damages DNA by converting two adjacent thymines into a thymine dimer which is potentially mutagenic, carcinogenic, or lethal to the organism. This damage is repaired by photolyase and the nucleotide excision repair system in E. coli by nucleotide excision repair in humans. The work leading to these results is presented by Aziz Sancar in his Nobel Lecture.
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Affiliation(s)
- Aziz Sancar
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.
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20
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Sancar A. Mechanismen der DNA-Reparatur durch Photolyasen und Exzisionsnukleasen (Nobel-Aufsatz). Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601524] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Aziz Sancar
- Department of Biochemistry and Biophysics; University of North Carolina School of Medicine; Chapel Hill North Carolina USA
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21
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Abstract
Plants use light for photosynthesis and for various signaling purposes. The UV wavelengths in sunlight also introduce DNA damage in the form of cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts [(6-4)PPs] that must be repaired for the survival of the plant. Genome sequencing has revealed the presence of genes for both CPD and (6-4)PP photolyases, as well as genes for nucleotide excision repair in plants, such as Arabidopsis and rice. Plant photolyases have been purified, characterized, and have been shown to play an important role in plant survival. In contrast, even though nucleotide excision repair gene homologs have been found in plants, the mechanism of nucleotide excision repair has not been investigated. Here we used the in vivo excision repair assay developed in our laboratory to demonstrate that Arabidopsis removes CPDs and (6-4)PPs by a dual-incision mechanism that is essentially identical to the mechanism of dual incisions in humans and other eukaryotes, in which oligonucleotides with a mean length of 26-27 nucleotides are removed by incising ∼20 phosphodiester bonds 5' and 5 phosphodiester bonds 3' to the photoproduct.
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22
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Kemp MG, Sancar A. ATR Kinase Inhibition Protects Non-cycling Cells from the Lethal Effects of DNA Damage and Transcription Stress. J Biol Chem 2016; 291:9330-42. [PMID: 26940878 DOI: 10.1074/jbc.m116.719740] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Indexed: 01/09/2023] Open
Abstract
ATR (ataxia telangiectasia and Rad-3-related) is a protein kinase that maintains genome stability and halts cell cycle phase transitions in response to DNA lesions that block DNA polymerase movement. These DNA replication-associated features of ATR function have led to the emergence of ATR kinase inhibitors as potential adjuvants for DNA-damaging cancer chemotherapeutics. However, whether ATR affects the genotoxic stress response in non-replicating, non-cycling cells is currently unknown. We therefore used chemical inhibition of ATR kinase activity to examine the role of ATR in quiescent human cells. Although ATR inhibition had no obvious effects on the viability of non-cycling cells, inhibition of ATR partially protected non-replicating cells from the lethal effects of UV and UV mimetics. Analyses of various DNA damage response signaling pathways demonstrated that ATR inhibition reduced the activation of apoptotic signaling by these agents in non-cycling cells. The pro-apoptosis/cell death function of ATR is likely due to transcription stress because the lethal effects of compounds that block RNA polymerase movement were reduced in the presence of an ATR inhibitor. These results therefore suggest that whereas DNA polymerase stalling at DNA lesions activates ATR to protect cell viability and prevent apoptosis, the stalling of RNA polymerases instead activates ATR to induce an apoptotic form of cell death in non-cycling cells. These results have important implications regarding the use of ATR inhibitors in cancer chemotherapy regimens.
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Affiliation(s)
- Michael G Kemp
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | - Aziz Sancar
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
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23
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Tripartite DNA Lesion Recognition and Verification by XPC, TFIIH, and XPA in Nucleotide Excision Repair. Mol Cell 2015; 59:1025-34. [PMID: 26384665 DOI: 10.1016/j.molcel.2015.08.012] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 07/09/2015] [Accepted: 08/17/2015] [Indexed: 11/23/2022]
Abstract
Transcription factor IIH (TFIIH) is essential for both transcription and nucleotide excision repair (NER). DNA lesions are initially detected by NER factors XPC and XPE or stalled RNA polymerases, but only bulky lesions are preferentially repaired by NER. To elucidate substrate specificity in NER, we have prepared homogeneous human ten-subunit TFIIH and its seven-subunit core (Core7) without the CAK module and show that bulky lesions in DNA inhibit the ATPase and helicase activities of both XPB and XPD in Core7 to promote NER, whereas non-genuine NER substrates have no such effect. Moreover, the NER factor XPA activates unwinding of normal DNA by Core7, but inhibits the Core7 helicase activity in the presence of bulky lesions. Finally, the CAK module inhibits DNA binding by TFIIH and thereby enhances XPC-dependent specific recruitment of TFIIH. Our results support a tripartite lesion verification mechanism involving XPC, TFIIH, and XPA for efficient NER.
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24
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Lindsey-Boltz LA, Kemp MG, Hu J, Sancar A. Analysis of Ribonucleotide Removal from DNA by Human Nucleotide Excision Repair. J Biol Chem 2015; 290:29801-7. [PMID: 26491008 DOI: 10.1074/jbc.m115.695254] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Indexed: 11/06/2022] Open
Abstract
Ribonucleotides are incorporated into the genome during DNA replication. The enzyme RNase H2 plays a critical role in targeting the removal of these ribonucleotides from DNA, and defects in RNase H2 activity are associated with both genomic instability and the human autoimmune/inflammatory disorder Aicardi-Goutières syndrome. Whether additional general DNA repair mechanisms contribute to ribonucleotide removal from DNA in human cells is not known. Because of its ability to act on a wide variety of substrates, we examined a potential role for canonical nucleotide excision repair in the removal of ribonucleotides from DNA. However, using highly sensitive dual incision/excision assays, we find that ribonucleotides are not efficiently targeted by the human nucleotide excision repair system in vitro or in cultured human cells. These results suggest that nucleotide excision repair is unlikely to play a major role in the cellular response to ribonucleotide incorporation in genomic DNA in human cells.
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Affiliation(s)
- Laura A Lindsey-Boltz
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | - Michael G Kemp
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | - Jinchuan Hu
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | - Aziz Sancar
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
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25
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Choi JH, Kim SY, Kim SK, Kemp MG, Sancar A. An Integrated Approach for Analysis of the DNA Damage Response in Mammalian Cells: NUCLEOTIDE EXCISION REPAIR, DNA DAMAGE CHECKPOINT, AND APOPTOSIS. J Biol Chem 2015; 290:28812-21. [PMID: 26438822 DOI: 10.1074/jbc.m115.690354] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Indexed: 11/06/2022] Open
Abstract
DNA damage by UV and UV-mimetic agents elicits a set of inter-related responses in mammalian cells, including DNA repair, DNA damage checkpoints, and apoptosis. Conventionally, these responses are analyzed separately using different methodologies. Here we describe a unified approach that is capable of quantifying all three responses in parallel using lysates from the same population of cells. We show that a highly sensitive in vivo excision repair assay is capable of detecting nucleotide excision repair of a wide spectrum of DNA lesions (UV damage, chemical carcinogens, and chemotherapeutic drugs) within minutes of damage induction. This method therefore allows for a real-time measure of nucleotide excision repair activity that can be monitored in conjunction with other components of the DNA damage response, including DNA damage checkpoint and apoptotic signaling. This approach therefore provides a convenient and reliable platform for simultaneously examining multiple aspects of the DNA damage response in a single population of cells that can be applied for a diverse array of carcinogenic and chemotherapeutic agents.
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Affiliation(s)
- Jun-Hyuk Choi
- From the Center for Bioanalysis, Department of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Daejeon 305-340, South Korea, the Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-350, South Korea, and
| | - So-Young Kim
- From the Center for Bioanalysis, Department of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Daejeon 305-340, South Korea
| | - Sook-Kyung Kim
- From the Center for Bioanalysis, Department of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Daejeon 305-340, South Korea, the Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-350, South Korea, and
| | - Michael G Kemp
- the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260
| | - Aziz Sancar
- the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260
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26
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Hu J, Adar S, Selby CP, Lieb JD, Sancar A. Genome-wide analysis of human global and transcription-coupled excision repair of UV damage at single-nucleotide resolution. Genes Dev 2015; 29:948-60. [PMID: 25934506 PMCID: PMC4421983 DOI: 10.1101/gad.261271.115] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hu et al. developed a method for genome-wide mapping of DNA excision repair named XR-seq (excision repair sequencing) and used it to produce stranded, nucleotide-resolution maps of repair of two UV-induced DNA damages in human cells. XR-seq and the resulting repair maps will facilitate studies of the effects of genomic location, chromatin context, transcription, and replication on DNA repair in human cells. We developed a method for genome-wide mapping of DNA excision repair named XR-seq (excision repair sequencing). Human nucleotide excision repair generates two incisions surrounding the site of damage, creating an ∼30-mer. In XR-seq, this fragment is isolated and subjected to high-throughput sequencing. We used XR-seq to produce stranded, nucleotide-resolution maps of repair of two UV-induced DNA damages in human cells: cyclobutane pyrimidine dimers (CPDs) and (6-4) pyrimidine–pyrimidone photoproducts [(6-4)PPs]. In wild-type cells, CPD repair was highly associated with transcription, specifically with the template strand. Experiments in cells defective in either transcription-coupled excision repair or general excision repair isolated the contribution of each pathway to the overall repair pattern and showed that transcription-coupled repair of both photoproducts occurs exclusively on the template strand. XR-seq maps capture transcription-coupled repair at sites of divergent gene promoters and bidirectional enhancer RNA (eRNA) production at enhancers. XR-seq data also uncovered the repair characteristics and novel sequence preferences of CPDs and (6-4)PPs. XR-seq and the resulting repair maps will facilitate studies of the effects of genomic location, chromatin context, transcription, and replication on DNA repair in human cells.
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Affiliation(s)
- Jinchuan Hu
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Sheera Adar
- Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | - Christopher P Selby
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Jason D Lieb
- Department of Human Genetics, University of Chicago, Chicago, Illinois 60637, USA
| | - Aziz Sancar
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA;
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27
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Kemp MG, Lindsey-Boltz LA, Sancar A. UV Light Potentiates STING (Stimulator of Interferon Genes)-dependent Innate Immune Signaling through Deregulation of ULK1 (Unc51-like Kinase 1). J Biol Chem 2015; 290:12184-94. [PMID: 25792739 PMCID: PMC4424351 DOI: 10.1074/jbc.m115.649301] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 03/19/2015] [Indexed: 01/04/2023] Open
Abstract
The mechanism by which ultraviolet (UV) wavelengths of sunlight trigger or exacerbate the symptoms of the autoimmune disorder lupus erythematosus is not known but may involve a role for the innate immune system. Here we show that UV radiation potentiates STING (stimulator of interferon genes)-dependent activation of the immune signaling transcription factor interferon regulatory factor 3 (IRF3) in response to cytosolic DNA and cyclic dinucleotides in keratinocytes and other human cells. Furthermore, we find that modulation of this innate immune response also occurs with UV-mimetic chemical carcinogens and in a manner that is independent of DNA repair and several DNA damage and cell stress response signaling pathways. Rather, we find that the stimulation of STING-dependent IRF3 activation by UV is due to apoptotic signaling-dependent disruption of ULK1 (Unc51-like kinase 1), a pro-autophagic protein that negatively regulates STING. Thus, deregulation of ULK1 signaling by UV-induced DNA damage may contribute to the negative effects of sunlight UV exposure in patients with autoimmune disorders.
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Affiliation(s)
- Michael G Kemp
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | - Laura A Lindsey-Boltz
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | - Aziz Sancar
- From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
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28
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Bee L, Marini S, Pontarin G, Ferraro P, Costa R, Albrecht U, Celotti L. Nucleotide excision repair efficiency in quiescent human fibroblasts is modulated by circadian clock. Nucleic Acids Res 2015; 43:2126-37. [PMID: 25662220 PMCID: PMC4344517 DOI: 10.1093/nar/gkv081] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The efficiency of Nucleotide Excision Repair (NER)process is crucial for maintaining genomic integrity because in many organisms, including humans, it represents the only system able to repair a wide range of DNA damage. The aim of the work was to investigate whether the efficiency of the repair of photoproducts induced by UV-light is affected by the circadian phase at which irradiation occurred. NER activity has been analyzed in human quiescent fibroblasts (in the absence of the cell cycle effect), in which circadian rhythmicity has been synchronized with a pulse of dexamethasone. Our results demonstrate that both DNA damage induction and repair efficiency are strictly dependent on the phase of the circadian rhythm at which the cells are UV-exposed. Furthermore, the differences observed between fibroblasts irradiated at different circadian times (CTs) are abolished when the clock is obliterated. In addition, we observe that chromatin structure is regulated by circadian rhythmicity. Maximal chromatin relaxation occurred at the same CT when photoproduct formation and removal were highest. Our data suggest that the circadian clock regulates both the DNA sensitivity to UV damage and the efficiency of NER by controlling chromatin condensation mainly through histone acetylation.
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Affiliation(s)
- Leonardo Bee
- Department of Biology, University of Padova, Padova 35131, Italy
| | - Selena Marini
- Department of Biology, University of Padova, Padova 35131, Italy
| | | | - Paola Ferraro
- Department of Biology, University of Padova, Padova 35131, Italy
| | - Rodolfo Costa
- Department of Biology, University of Padova, Padova 35131, Italy
| | - Urs Albrecht
- Department of Biology, Unit for Biochemistry, University of Fribourg, Fribourg CH-1700, Switzerland
| | - Lucia Celotti
- Department of Biology, University of Padova, Padova 35131, Italy
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