1
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Gao S, Tahara Y, Kool E, Greenberg M. Promoter dependent RNA polymerase II bypass of the epimerizable DNA lesion, Fapy•dG and 8-Oxo-2'-deoxyguanosine. Nucleic Acids Res 2024; 52:7437-7446. [PMID: 38908029 PMCID: PMC11260475 DOI: 10.1093/nar/gkae529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 05/30/2024] [Accepted: 06/10/2024] [Indexed: 06/24/2024] Open
Abstract
Formamidopyrimidine (Fapy•dG) is a major lesion arising from oxidation of dG that is produced from a common chemical precursor of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OxodGuo). In human cells, replication of single-stranded shuttle vectors containing Fapy•dG is more mutagenic than 8-OxodGuo. Here, we present the first data regarding promoter dependent RNA polymerase II bypass of Fapy•dG. 8-OxodGuo bypass was examined side-by-side. Experiments were carried out using double-stranded shuttle vectors in HeLa cell nuclear lysates and in HEK 293T cells. The lesions do not significantly block transcriptional bypass efficiency. Less than 2% adenosine incorporation occurred in cells when the lesions were base paired with dC. Inhibiting base excision repair in HEK 293T cells significantly increased adenosine incorporation, particularly from Fapy•dG:dC bypass which yielded ∼25% adenosine incorporation. No effect was detected upon transcriptional bypass of either lesion in nucleotide excision repair deficient cells. Transcriptional mutagenesis was significantly higher when shuttle vectors containing dA opposite one of the lesions were employed. For Fapy•dG:dA bypass, adenosine incorporation was greater than 85%; whereas 8-OxodGuo:dA yielded >20% point mutations. The combination of more frequent replication mistakes and greater error-prone Pol II bypass suggest that Fapy•dG is more mutagenic than 8-OxodGuo.
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Affiliation(s)
- Shijun Gao
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Yuki Tahara
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Eric T Kool
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Marc M Greenberg
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA
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2
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Yudkina AV, Kim DV, Zharkov TD, Zharkov DO, Endutkin AV. Probing the Conformational Restraints of DNA Damage Recognition with β-L-Nucleotides. Int J Mol Sci 2024; 25:6006. [PMID: 38892193 PMCID: PMC11172447 DOI: 10.3390/ijms25116006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 05/28/2024] [Accepted: 05/28/2024] [Indexed: 06/21/2024] Open
Abstract
The DNA building blocks 2'-deoxynucleotides are enantiomeric, with their natural β-D-configuration dictated by the sugar moiety. Their synthetic β-L-enantiomers (βLdNs) can be used to obtain L-DNA, which, when fully substituted, is resistant to nucleases and is finding use in many biosensing and nanotechnology applications. However, much less is known about the enzymatic recognition and processing of individual βLdNs embedded in D-DNA. Here, we address the template properties of βLdNs for several DNA polymerases and the ability of base excision repair enzymes to remove these modifications from DNA. The Klenow fragment was fully blocked by βLdNs, whereas DNA polymerase κ bypassed them in an error-free manner. Phage RB69 DNA polymerase and DNA polymerase β treated βLdNs as non-instructive but the latter enzyme shifted towards error-free incorporation on a gapped DNA substrate. DNA glycosylases and AP endonucleases did not process βLdNs. DNA glycosylases sensitive to the base opposite their cognate lesions also did not recognize βLdNs as a correct pairing partner. Nevertheless, when placed in a reporter plasmid, pyrimidine βLdNs were resistant to repair in human cells, whereas purine βLdNs appear to be partly repaired. Overall, βLdNs are unique modifications that are mostly non-instructive but have dual non-instructive/instructive properties in special cases.
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Affiliation(s)
- Anna V. Yudkina
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (A.V.Y.); (D.V.K.); (T.D.Z.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
| | - Daria V. Kim
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (A.V.Y.); (D.V.K.); (T.D.Z.)
| | - Timofey D. Zharkov
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (A.V.Y.); (D.V.K.); (T.D.Z.)
| | - Dmitry O. Zharkov
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (A.V.Y.); (D.V.K.); (T.D.Z.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
| | - Anton V. Endutkin
- Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia; (A.V.Y.); (D.V.K.); (T.D.Z.)
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3
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Fan T, Shi T, Sui R, Wang J, Kang H, Yu Y, Zhu Y. The chromatin remodeler ERCC6 and the histone chaperone NAP1 are involved in apurinic/apyrimidinic endonuclease-mediated DNA repair. THE PLANT CELL 2024; 36:2238-2252. [PMID: 38367203 PMCID: PMC11132878 DOI: 10.1093/plcell/koae052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 01/26/2024] [Accepted: 01/28/2024] [Indexed: 02/19/2024]
Abstract
During base excision repair (BER), the apurinic or apyrimidinic (AP) site serves as an intermediate product following base excision. In plants, APE-redox protein (ARP) represents the major AP site of cleavage activity. Despite the well-established understanding that the nucleosomal structure acts as a barrier to various DNA-templated processes, the regulatory mechanisms underlying BER at the chromatin level remain elusive, especially in plants. In this study, we identified plant chromatin remodeler Excision Repair Cross-Complementing protein group 6 (ERCC6) and histone chaperone Nucleosome Assembly Protein 1 (NAP1) as interacting proteins with ARP. The catalytic ATPase domain of ERCC6 facilitates its interaction with both ARP and NAP1. Additionally, ERCC6 and NAP1 synergistically contribute to nucleosome sliding and exposure of hindered endonuclease cleavage sites. Loss-of-function mutations in Arabidopsis (Arabidopsis thaliana) ERCC6 or NAP1 resulted in arp-dependent plant hypersensitivity to 5-fluorouracil, a toxic agent inducing BER, and the accumulation of AP sites. Furthermore, similar protein interactions are also found in yeast cells, suggesting a conserved recruitment mechanism employed by the AP endonuclease to overcome chromatin barriers during BER progression.
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Affiliation(s)
- Tianyi Fan
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Tianfang Shi
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai 200438, China
| | - Ran Sui
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jingqi Wang
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai 200438, China
| | - Huijia Kang
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
| | - Yao Yu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai 200438, China
| | - Yan Zhu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
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4
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Pfeifer GP. DNA Damage and Parkinson's Disease. Int J Mol Sci 2024; 25:4187. [PMID: 38673772 PMCID: PMC11050701 DOI: 10.3390/ijms25084187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 03/20/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024] Open
Abstract
The etiology underlying most sporadic Parkinson's' disease (PD) cases is unknown. Environmental exposures have been suggested as putative causes of the disease. In cell models and in animal studies, certain chemicals can destroy dopaminergic neurons. However, the mechanisms of how these chemicals cause the death of neurons is not understood. Several of these agents are mitochondrial toxins that inhibit the mitochondrial complex I of the electron transport chain. Familial PD genes also encode proteins with important functions in mitochondria. Mitochondrial dysfunction of the respiratory chain, in combination with the presence of redox active dopamine molecules in these cells, will lead to the accumulation of reactive oxygen species (ROS) in dopaminergic neurons. Here, I propose a mechanism regarding how ROS may lead to cell killing with a specificity for neurons. One rarely considered hypothesis is that ROS produced by defective mitochondria will lead to the formation of oxidative DNA damage in nuclear DNA. Many genes that encode proteins with neuron-specific functions are extraordinary long, ranging in size from several hundred kilobases to well over a megabase. It is predictable that such long genes will contain large numbers of damaged DNA bases, for example in the form of 8-oxoguanine (8-oxoG), which is a major DNA damage type produced by ROS. These DNA lesions will slow down or stall the progression of RNA polymerase II, which is a term referred to as transcription stress. Furthermore, ROS-induced DNA damage may cause mutations, even in postmitotic cells such as neurons. I propose that the impaired transcription and mutagenesis of long, neuron-specific genes will lead to a loss of neuronal integrity, eventually leading to the death of these cells during a human lifetime.
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Affiliation(s)
- Gerd P Pfeifer
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA
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5
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Steele EJ, Franklin A, Lindley RA. Somatic mutation patterns at Ig and Non-Ig Loci. DNA Repair (Amst) 2024; 133:103607. [PMID: 38056368 DOI: 10.1016/j.dnarep.2023.103607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 11/17/2023] [Accepted: 11/21/2023] [Indexed: 12/08/2023]
Abstract
The reverse transcriptase (RT) model of immunoglobulin (Ig) somatic hypermutation (SHM) has received insufficient scientific attention. This is understandable given that DNA deamination mediated by activation-induced deaminase (AID), the initiating step of Ig SHM, has dominated experiments since 2002. We summarise some key history of the RT Ig SHM model dating to 1987. For example, it is now established that DNA polymerase η, the sole DNA repair polymerase involved in post-replication short-patch repair, is an efficient cellular RT. This implies that it is potentially able to initiate target site reverse transcription by RNA-directed DNA repair at AID-induced lesions. Recently, DNA polymerase θ has also been shown to be an efficient cellular RT. Since DNA polymerase θ plays no significant role in Ig SHM, it could serve a similar RNA-dependent DNA polymerase role as DNA polymerase η at non-Ig loci in the putative RNA-templated nucleotide excision repair of bulky adducts and other mutagenic lesions on the transcribed strand. A major yet still poorly recognised consequence of the proposed RT process in Ig SHM is the generation of significant and characteristic strand-biased mutation signatures at both deoxyadenosine/deoxythymidine and deoxyguanosine/deoxycytidine base pairs. In this historical perspective, we highlight how diagnostic strand-biased mutation signatures are detected in vivo during SHM at both Ig loci in germinal centre B lymphocytes and non-Ig loci in cancer genomes. These strand-biased signatures have been significantly obscured by technical issues created by improper use of the polymerase chain reaction technique. A heightened awareness of this fact should contribute to better data interpretation and somatic mutation pattern recognition both at Ig and non-Ig loci.
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Affiliation(s)
- Edward J Steele
- Melville Analytics Pty Ltd, 2/102 Duke St, Kangaroo Point, Brisbane 4169, Qld, Australia.
| | - Andrew Franklin
- Novartis Pharmaceuticals UK Limited, The WestWorks Building, White City Place, 195 Wood Lane, W12 7FQ London, United Kingdom
| | - Robyn A Lindley
- GMDxgenomics, Suite 201, 697 Burke Rd, Camberwell, Melbourne 3124, Vic, Australia; Department of Clinical Pathology, Faculty of Medicine, Dentistry & Health Sciences, University of Melbourne, Vic, Australia
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6
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Gohil D, Sarker AH, Roy R. Base Excision Repair: Mechanisms and Impact in Biology, Disease, and Medicine. Int J Mol Sci 2023; 24:14186. [PMID: 37762489 PMCID: PMC10531636 DOI: 10.3390/ijms241814186] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/12/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Base excision repair (BER) corrects forms of oxidative, deamination, alkylation, and abasic single-base damage that appear to have minimal effects on the helix. Since its discovery in 1974, the field has grown in several facets: mechanisms, biology and physiology, understanding deficiencies and human disease, and using BER genes as potential inhibitory targets to develop therapeutics. Within its segregation of short nucleotide (SN-) and long patch (LP-), there are currently six known global mechanisms, with emerging work in transcription- and replication-associated BER. Knockouts (KOs) of BER genes in mouse models showed that single glycosylase knockout had minimal phenotypic impact, but the effects were clearly seen in double knockouts. However, KOs of downstream enzymes showed critical impact on the health and survival of mice. BER gene deficiency contributes to cancer, inflammation, aging, and neurodegenerative disorders. Medicinal targets are being developed for single or combinatorial therapies, but only PARP and APE1 have yet to reach the clinical stage.
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Affiliation(s)
- Dhara Gohil
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA;
| | - Altaf H. Sarker
- Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA;
| | - Rabindra Roy
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA;
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7
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Laughery MF, Plummer DA, Wilson HE, Vandenberg BN, Mitchell D, Mieczkowski PA, Roberts SA, Wyrick JJ. Genome-wide maps of UVA and UVB mutagenesis in yeast reveal distinct causative lesions and mutational strand asymmetries. Genetics 2023; 224:iyad086. [PMID: 37170598 PMCID: PMC10324949 DOI: 10.1093/genetics/iyad086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 05/01/2023] [Accepted: 05/03/2023] [Indexed: 05/13/2023] Open
Abstract
Ultraviolet (UV) light primarily causes C > T substitutions in lesion-forming dipyrimidine sequences. However, many of the key driver mutations in melanoma do not fit this canonical UV signature, but are instead caused by T > A, T > C, or C > A substitutions. To what extent exposure to the UVB or UVA spectrum of sunlight can induce these noncanonical mutation classes, and the molecular mechanism involved is unclear. Here, we repeatedly exposed wild-type or repair-deficient yeast (Saccharomyces cerevisiae) to UVB or UVA light and characterized the resulting mutations by whole genome sequencing. Our data indicate that UVB induces C > T and T > C substitutions in dipyrimidines, and T > A substitutions that are often associated with thymine-adenine (TA) sequences. All of these mutation classes are induced in nucleotide excision repair-deficient cells and show transcriptional strand asymmetry, suggesting they are caused by helix-distorting UV photoproducts. In contrast, UVA exposure induces orders of magnitude fewer mutations with a distinct mutation spectrum. UVA-induced mutations are elevated in Ogg1-deficient cells, and the resulting spectrum consists almost entirely of C > A/G > T mutations, indicating they are likely derived from oxidative guanine lesions. These mutations show replication asymmetry, with elevated G > T mutations on the leading strand, suggesting there is a strand bias in the removal or bypass of guanine lesions during replication. Finally, we develop a mutation reporter to show that UVA induces a G > T reversion mutation in yeast that mimics the oncogenic NRAS Q61K mutation in melanoma. Taken together, these findings indicate that UVA and UVB exposure can induce many of the noncanonical mutation classes that cause driver mutations in melanoma.
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Affiliation(s)
- Marian F Laughery
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA
| | - Dalton A Plummer
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA
| | - Hannah E Wilson
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA
| | - Brittany N Vandenberg
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA
| | - Debra Mitchell
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA
| | - Piotr A Mieczkowski
- Department of Genetics, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Steven A Roberts
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA
- Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - John J Wyrick
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA
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8
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Xu M, Liu Y, Wan HL, Wong AM, Ding X, You W, Lo WS, Ng KKC, Wong N. Overexpression of nucleotide metabolic enzyme DUT in hepatocellular carcinoma potentiates a therapeutic opportunity through targeting its dUTPase activity. Cancer Lett 2022; 548:215898. [PMID: 36075487 DOI: 10.1016/j.canlet.2022.215898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 07/24/2022] [Accepted: 08/24/2022] [Indexed: 11/26/2022]
Abstract
Uracil misincorporation during DNA replication is a major cell toxic event, of which cancer cells overcome by activating the dUTPase enzyme. The DUT gene is the only known dUTPase in human. Despite reports on common upregulations in cancers, the role of DUT in human hepatocellular carcinoma (HCC) remains largely undetermined. In this study, we investigated the mechanism underlying DUT biology in HCC and tumor susceptibility to drug targeting dUTPase. Overexpression of DUT was found in 42% of HCC tumors and correlated with advanced stage HCC. Knockout of DUT in HCC cell lines showed suppressed proliferation through cell cycle arrest and a spontaneous induction of DNA damage. A protective effect from oxidative stress was also demonstrated in both knockout and overexpression DUT assays. Transcriptome analysis highlighted the NF-κB survival signaling as the downstream effector pathway of DUT in overriding oxidative stress-induced cell death. Interestingly, stably expressed DUT in liver progenitor organoids conferred drug resistance to TKI Sorafenib. Targeting dUTPase activity by TAS-114, could potentiate suppression of HCC growth that synergized with Sorafenib for better treatment sensitivity. In conclusion, upregulated DUT represents a nucleotide metabolic weakness and therapeutic opportunity in HCC.
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Affiliation(s)
- Mingjing Xu
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Yue Liu
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Ho Lee Wan
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Alissa M Wong
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Xiaofan Ding
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Wenxing You
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Wing Sze Lo
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Kelvin K-C Ng
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Nathalie Wong
- Department of Surgery, Sir Y.K. Pao Centre for Cancer, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China; State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
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9
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Hahm JY, Park J, Jang ES, Chi SW. 8-Oxoguanine: from oxidative damage to epigenetic and epitranscriptional modification. Exp Mol Med 2022; 54:1626-1642. [PMID: 36266447 PMCID: PMC9636213 DOI: 10.1038/s12276-022-00822-z] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 05/06/2022] [Accepted: 05/26/2022] [Indexed: 12/29/2022] Open
Abstract
In pathophysiology, reactive oxygen species control diverse cellular phenotypes by oxidizing biomolecules. Among these, the guanine base in nucleic acids is the most vulnerable to producing 8-oxoguanine, which can pair with adenine. Because of this feature, 8-oxoguanine in DNA (8-oxo-dG) induces a G > T (C > A) mutation in cancers, which can be deleterious and thus actively repaired by DNA repair pathways. 8-Oxoguanine in RNA (o8G) causes problems in aberrant quality and translational fidelity, thereby it is subjected to the RNA decay pathway. In addition to oxidative damage, 8-oxo-dG serves as an epigenetic modification that affects transcriptional regulatory elements and other epigenetic modifications. With the ability of o8G•A in base pairing, o8G alters structural and functional RNA-RNA interactions, enabling redirection of posttranscriptional regulation. Here, we address the production, regulation, and function of 8-oxo-dG and o8G under oxidative stress. Primarily, we focus on the epigenetic and epitranscriptional roles of 8-oxoguanine, which highlights the significance of oxidative modification in redox-mediated control of gene expression.
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Affiliation(s)
- Ja Young Hahm
- grid.222754.40000 0001 0840 2678Department of Life Sciences, Korea University, Seoul, 02481 Republic of Korea ,grid.222754.40000 0001 0840 2678Institute of Life Sciences and Biotechnology, Korea University, Seoul, 02481 Republic of Korea
| | - Jongyeun Park
- grid.222754.40000 0001 0840 2678Department of Life Sciences, Korea University, Seoul, 02481 Republic of Korea ,grid.222754.40000 0001 0840 2678Institute of Life Sciences and Biotechnology, Korea University, Seoul, 02481 Republic of Korea
| | - Eun-Sook Jang
- grid.222754.40000 0001 0840 2678Department of Life Sciences, Korea University, Seoul, 02481 Republic of Korea ,grid.222754.40000 0001 0840 2678Institute of Life Sciences and Biotechnology, Korea University, Seoul, 02481 Republic of Korea
| | - Sung Wook Chi
- grid.222754.40000 0001 0840 2678Department of Life Sciences, Korea University, Seoul, 02481 Republic of Korea ,grid.222754.40000 0001 0840 2678Institute of Life Sciences and Biotechnology, Korea University, Seoul, 02481 Republic of Korea ,grid.222754.40000 0001 0840 2678KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02481 Republic of Korea
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10
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Xue Z, Demple B. Knockout and Inhibition of Ape1: Roles of Ape1 in Base Excision DNA Repair and Modulation of Gene Expression. Antioxidants (Basel) 2022; 11:antiox11091817. [PMID: 36139891 PMCID: PMC9495735 DOI: 10.3390/antiox11091817] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/31/2022] [Accepted: 09/07/2022] [Indexed: 11/21/2022] Open
Abstract
Apurinic/apyrimidinic endonuclease 1/redox effector-1 (Ape1/Ref-1) is the major apurinic/apyrimidinic (AP) endonuclease in mammalian cells. It functions mainly in the base excision repair pathway to create a suitable substrate for DNA polymerases. Human Ape1 protein can activate some transcription factors to varying degrees, dependent on its N-terminal, unstructured domain, and some of the cysteines within it, apparently via a redox mechanism in some cases. Many cancer studies also suggest that Ape1 has potential for prognosis in terms of the protein level or intracellular localization. While homozygous disruption of the Ape1 structural gene APEX1 in mice causes embryonic lethality, and most studies in cell culture indicate that the expression of Ape1 is essential, some recent studies reported the isolation of viable APEX1 knockout cells with only mild phenotypes. It has not been established by what mechanism the Ape1-null cell lines cope with the endogenous DNA damage that the enzyme normally handles. We review the enzymatic and other activities of Ape1 and the recent studies of the properties of the APEX1 knockout lines. The APEX1 deletions in CH12F3 and HEK293 FT provide an opportunity to test for possible off-target effects of Ape1 inhibition. For this work, we tested the Ape1 endonuclease inhibitor Compound 3 and the redox inhibitor APX2009. Our results confirmed that both APEX1 knockout cell lines are modestly more sensitive to killing by an alkylating agent than their Ape1-proficient cells. Surprisingly, the knockout lines showed equal sensitivity to direct killing by either inhibitor, despite the lack of the target protein. Moreover, the CH12F3 APEX1 knockout was even more sensitive to Compound 3 than its APEX1+ counterpart. Thus, it appears that both Compound 3 and APX2009 have off-target effects. In cases where this issue may be important, it is advisable that more specific endpoints than cell survival be tested for establishing mechanism.
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Affiliation(s)
- Zhouyiyuan Xue
- Department of Pharmacological Sciences, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794-8651, USA
- Molecular and Cellular Biochemistry Program, Stony Brook University, Stony Brook, NY 11794-8651, USA
| | - Bruce Demple
- Department of Pharmacological Sciences, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794-8651, USA
- Correspondence: ; Tel.: +1-(631)-444-3978
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11
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Agapov A, Olina A, Kulbachinskiy A. OUP accepted manuscript. Nucleic Acids Res 2022; 50:3018-3041. [PMID: 35323981 PMCID: PMC8989532 DOI: 10.1093/nar/gkac174] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 02/26/2022] [Accepted: 03/03/2022] [Indexed: 11/14/2022] Open
Abstract
Cellular DNA is continuously transcribed into RNA by multisubunit RNA polymerases (RNAPs). The continuity of transcription can be disrupted by DNA lesions that arise from the activities of cellular enzymes, reactions with endogenous and exogenous chemicals or irradiation. Here, we review available data on translesion RNA synthesis by multisubunit RNAPs from various domains of life, define common principles and variations in DNA damage sensing by RNAP, and consider existing controversies in the field of translesion transcription. Depending on the type of DNA lesion, it may be correctly bypassed by RNAP, or lead to transcriptional mutagenesis, or result in transcription stalling. Various lesions can affect the loading of the templating base into the active site of RNAP, or interfere with nucleotide binding and incorporation into RNA, or impair RNAP translocation. Stalled RNAP acts as a sensor of DNA damage during transcription-coupled repair. The outcome of DNA lesion recognition by RNAP depends on the interplay between multiple transcription and repair factors, which can stimulate RNAP bypass or increase RNAP stalling, and plays the central role in maintaining the DNA integrity. Unveiling the mechanisms of translesion transcription in various systems is thus instrumental for understanding molecular pathways underlying gene regulation and genome stability.
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Affiliation(s)
- Aleksei Agapov
- Correspondence may also be addressed to Aleksei Agapov. Tel: +7 499 196 0015; Fax: +7 499 196 0015;
| | - Anna Olina
- Institute of Molecular Genetics, National Research Center “Kurchatov Institute” Moscow 123182, Russia
| | - Andrey Kulbachinskiy
- To whom correspondence should be addressed. Tel: +7 499 196 0015; Fax: +7 499 196 0015;
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12
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Adamowicz M, Hailstone R, Demin AA, Komulainen E, Hanzlikova H, Brazina J, Gautam A, Wells SE, Caldecott KW. XRCC1 protects transcription from toxic PARP1 activity during DNA base excision repair. Nat Cell Biol 2021; 23:1287-1298. [PMID: 34811483 PMCID: PMC8683375 DOI: 10.1038/s41556-021-00792-w] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 10/11/2021] [Indexed: 11/22/2022]
Abstract
Genetic defects in the repair of DNA single-strand breaks (SSBs) can result in neurological disease triggered by toxic activity of the single-strand-break sensor protein PARP1. However, the mechanism(s) by which this toxic PARP1 activity triggers cellular dysfunction are unclear. Here we show that human cells lacking XRCC1 fail to rapidly recover transcription following DNA base damage, a phenotype also observed in patient-derived fibroblasts with XRCC1 mutations and Xrcc1−/− mouse neurons. This defect is caused by excessive/aberrant PARP1 activity during DNA base excision repair, resulting from the loss of PARP1 regulation by XRCC1. We show that aberrant PARP1 activity suppresses transcriptional recovery during base excision repair by promoting excessive recruitment and activity of the ubiquitin protease USP3, which as a result reduces the level of monoubiquitinated histones important for normal transcriptional regulation. Importantly, inhibition and/or deletion of PARP1 or USP3 restores transcriptional recovery in XRCC1−/− cells, highlighting PARP1 and USP3 as possible therapeutic targets in neurological disease. Adamowicz et al. report that toxic PARP1 activity, induced by ataxia-associated mutations in XRCC1, impairs the recovery of global transcription during DNA base excision repair by promoting aberrant recruitment and activity of the histone ubiquitin protease USP3.
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Affiliation(s)
- Marek Adamowicz
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Richard Hailstone
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Annie A Demin
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Emilia Komulainen
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Hana Hanzlikova
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK.,Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Science, Prague, Czech Republic
| | - Jan Brazina
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Amit Gautam
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Sophie E Wells
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Keith W Caldecott
- Genome Damage and Stability Centre and Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK. .,Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Science, Prague, Czech Republic.
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13
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Bhakat KK, Ray S. The FAcilitates Chromatin Transcription (FACT) complex: Its roles in DNA repair and implications for cancer therapy. DNA Repair (Amst) 2021; 109:103246. [PMID: 34847380 DOI: 10.1016/j.dnarep.2021.103246] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/07/2021] [Accepted: 11/03/2021] [Indexed: 12/17/2022]
Abstract
Genomic DNA in the nucleus is wrapped around nucleosomes, a repeating unit of chromatin. The nucleosome, consisting of octamer of core histones, is a barrier for several cellular processes that require access to the naked DNA. The FAcilitates Chromatin Transcription (FACT), a histone chaperone complex, is involved in nucleosome remodeling via eviction or assembly of histones during transcription, replication, and DNA repair. Increasing evidence suggests that FACT plays an important role in multiple DNA repair pathways including transcription-coupled nucleotide excision repair (TC-NER) of UV-induced damage, DNA single- and double-strand breaks (DSBs) repair, and base excision repair (BER) of oxidized or alkylated damaged bases. Further, studies have shown overexpression of FACT in multiple types of cancer and its association with drug resistance and patients' poor prognosis. In this review, we discuss how FACT is accumulated at the damage site and what functions it performs. We describe the known mechanisms by which FACT facilitates repair of different types of DNA damage. Further, we highlight the recent advances in a class of FACT inhibitors, called curaxins, which show promise as a new adjuvant therapy to sensitize multiple types of cancer to chemotherapy and radiation.
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Affiliation(s)
- Kishor K Bhakat
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, USA 68198; Fred and Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA 68198.
| | - Sutapa Ray
- Department of Pediatric, Division of Hematology/oncology, University of Nebraska Medical Center, Omaha, NE, USA 68198; Fred and Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA 68198
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14
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Chakraborty A, Tapryal N, Islam A, Mitra S, Hazra T. Transcription coupled base excision repair in mammalian cells: So little is known and so much to uncover. DNA Repair (Amst) 2021; 107:103204. [PMID: 34390916 DOI: 10.1016/j.dnarep.2021.103204] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 07/06/2021] [Accepted: 08/03/2021] [Indexed: 12/31/2022]
Abstract
Oxidized bases in the genome has been implicated in various human pathologies, including cancer, aging and neurological diseases. Their repair is initiated with excision by DNA glycosylases (DGs) in the base excision repair (BER) pathway. Among the five oxidized base-specific human DGs, OGG1 and NTH1 preferentially excise oxidized purines and pyrimidines, respectively, while NEILs remove both oxidized purines and pyrimidines. However, little is known about why cells possess multiple DGs with overlapping substrate specificities. Studies of the past decades revealed that some DGs are involved in repair of oxidized DNA base lesions in the actively transcribed regions. Preferential removal of lesions from the transcribed strands of active genes, called transcription-coupled repair (TCR), was discovered as a distinct sub-pathway of nucleotide excision repair; however, such repair of oxidized DNA bases had not been established until our recent demonstration of NEIL2's role in TC-BER of the nuclear genome. We have shown that NEIL2 forms a distinct transcriptionally active, repair proficient complex. More importantly, we for the first time reconstituted TC-BER using purified components. These studies are important for characterizing critical requirement for the process. However, because NEIL2 cannot remove all types of oxidized bases, it is unlikely to be the only DNA glycosylase involved in TC-BER. Hence, we postulate TC-BER process to be universally involved in maintaining the functional integrity of active genes, especially in post-mitotic, non-growing cells. We further postulate that abnormal bases (e.g., uracil), and alkylated and other small DNA base adducts are also repaired via TC-BER. In this review, we have provided an overview of the various aspects of TC-BER in mammalian cells with the hope of generating significant interest of many researchers in the field. Further studies aimed at better understanding the mechanistic aspects of TC-BER could help elucidate the linkage of TC-BER deficiency to various human pathologies.
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Affiliation(s)
- Anirban Chakraborty
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Nisha Tapryal
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Azharul Islam
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Sankar Mitra
- Department of Radiation Oncology, The Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Tapas Hazra
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, TX 77555, USA.
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15
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SenGupta T, Palikaras K, Esbensen YQ, Konstantinidis G, Galindo FJN, Achanta K, Kassahun H, Stavgiannoudaki I, Bohr VA, Akbari M, Gaare J, Tzoulis C, Tavernarakis N, Nilsen H. Base excision repair causes age-dependent accumulation of single-stranded DNA breaks that contribute to Parkinson disease pathology. Cell Rep 2021; 36:109668. [PMID: 34496255 PMCID: PMC8441048 DOI: 10.1016/j.celrep.2021.109668] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 05/26/2021] [Accepted: 08/13/2021] [Indexed: 01/24/2023] Open
Abstract
Aging, genomic stress, and mitochondrial dysfunction are risk factors for neurodegenerative pathologies, such as Parkinson disease (PD). Although genomic instability is associated with aging and mitochondrial impairment, the underlying mechanisms are poorly understood. Here, we show that base excision repair generates genomic stress, promoting age-related neurodegeneration in a Caenorhabditis elegans PD model. A physiological level of NTH-1 DNA glycosylase mediates mitochondrial and nuclear genomic instability, which promote degeneration of dopaminergic neurons in older nematodes. Conversely, NTH-1 deficiency protects against α-synuclein-induced neurotoxicity, maintaining neuronal function with age. This apparent paradox is caused by modulation of mitochondrial transcription in NTH-1-deficient cells, and this modulation activates LMD-3, JNK-1, and SKN-1 and induces mitohormesis. The dependance of neuroprotection on mitochondrial transcription highlights the integration of BER and transcription regulation during physiological aging. Finally, whole-exome sequencing of genomic DNA from patients with idiopathic PD suggests that base excision repair might modulate susceptibility to PD in humans. Incomplete base excision repair is a source of genomic stress during aging The NTH-1 DNA glycosylase is a key mediator of age-dependent genomic instability Compromised NTH-1 activity promotes neuroprotection in PD nematodes NTH-1 deficiency triggers LMD-3/JNK-1/SKN-1-dependent mitohormetic response
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Affiliation(s)
- Tanima SenGupta
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway
| | - Konstantinos Palikaras
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece; Department of Physiology, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Ying Q Esbensen
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway
| | - Georgios Konstantinidis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece
| | - Francisco Jose Naranjo Galindo
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway
| | - Kavya Achanta
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, SUND, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Henok Kassahun
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway
| | - Ioanna Stavgiannoudaki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece
| | - Vilhelm A Bohr
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, SUND, University of Copenhagen, 2200 Copenhagen, Denmark; DNA Repair Section, National Institute on Aging, 251 Bayview Boulevard, Baltimore, MD, USA
| | - Mansour Akbari
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, SUND, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Johannes Gaare
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, 5021 Bergen, Norway; Department of Clinical Medicine, University of Bergen, Pb 7804, 5020 Bergen, Norway
| | - Charalampos Tzoulis
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, 5021 Bergen, Norway; Department of Clinical Medicine, University of Bergen, Pb 7804, 5020 Bergen, Norway
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece; Department of Basic Sciences, Faculty of Medicine, University of Crete, Heraklion, 70013 Crete, Greece.
| | - Hilde Nilsen
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway.
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16
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Sarker AH, Cooper PK, Hazra TK. DNA glycosylase NEIL2 functions in multiple cellular processes. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 164:72-80. [PMID: 33753087 DOI: 10.1016/j.pbiomolbio.2021.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 03/09/2021] [Accepted: 03/16/2021] [Indexed: 12/24/2022]
Abstract
Cell survival largely depends on the faithful maintenance of genetic material since genomic DNA is constantly exposed to genotoxicants from both endogenous and exogenous sources. The evolutionarily conserved base excision repair (BER) pathway is critical for maintaining genome integrity by eliminating highly abundant and potentially mutagenic oxidized DNA base lesions. BER is a multistep process, which is initiated with recognition and excision of the DNA base lesion by a DNA glycosylase, followed by DNA end processing, gap filling and finally sealing of the nick. Besides genome maintenance by global BER, DNA glycosylases have been found to play additional roles, including preferential repair of oxidized lesions from transcribed genes, modulation of the immune response, participation in active DNA demethylation and maintenance of the mitochondrial genome. Central to these functions is the DNA glycosylase NEIL2. Its loss results in increased accumulation of oxidized base lesions in the transcribed genome, triggers an immune response and causes early neurodevelopmental defects, thus emphasizing the multitasking capabilities of this repair protein. Here we review the specialized functions of NEIL2 and discuss the consequences of its absence both in vitro and in vivo.
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Affiliation(s)
- Altaf H Sarker
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Priscilla K Cooper
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Tapas K Hazra
- University of Texas Medical Branch, Galveston, TX, 77555, USA
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17
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Bordin DL, Lirussi L, Nilsen H. Cellular response to endogenous DNA damage: DNA base modifications in gene expression regulation. DNA Repair (Amst) 2021; 99:103051. [PMID: 33540225 DOI: 10.1016/j.dnarep.2021.103051] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/15/2021] [Accepted: 01/18/2021] [Indexed: 12/19/2022]
Abstract
The integrity of the genetic information is continuously challenged by numerous genotoxic insults, most frequently in the form of oxidation, alkylation or deamination of the bases that result in DNA damage. These damages compromise the fidelity of the replication, and interfere with the progression and function of the transcription machineries. The DNA damage response (DDR) comprises a series of strategies to deal with DNA damage, including transient transcriptional inhibition, activation of DNA repair pathways and chromatin remodeling. Coordinated control of transcription and DNA repair is required to safeguardi cellular functions and identities. Here, we address the cellular responses to endogenous DNA damage, with a particular focus on the role of DNA glycosylases and the Base Excision Repair (BER) pathway, in conjunction with the DDR factors, in responding to DNA damage during the transcription process. We will also discuss functions of newly identified epigenetic and regulatory marks, such as 5-hydroxymethylcytosine and its oxidative products and 8-oxoguanine, that were previously considered only as DNA damages. In light of these resultsthe classical perception of DNA damage as detrimental for cellular processes are changing. and a picture emerges whereDNA glycosylases act as dynamic regulators of transcription, placing them at the intersection of DNA repair and gene expression modulation.
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Affiliation(s)
- Diana L Bordin
- Department of Clinical Molecular Biology, University of Oslo, 0318, Oslo, Norway; Department of Clinical Molecular Biology (EpiGen), Akershus University Hospital, 1478, Lørenskog, Norway
| | - Lisa Lirussi
- Department of Clinical Molecular Biology, University of Oslo, 0318, Oslo, Norway; Department of Clinical Molecular Biology (EpiGen), Akershus University Hospital, 1478, Lørenskog, Norway
| | - Hilde Nilsen
- Department of Clinical Molecular Biology, University of Oslo, 0318, Oslo, Norway; Department of Clinical Molecular Biology (EpiGen), Akershus University Hospital, 1478, Lørenskog, Norway.
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18
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Anagnostou M, Chung C, McGann E, Verheijen B, Kou Y, Chen L, Vermulst M. Transcription errors in aging and disease. TRANSLATIONAL MEDICINE OF AGING 2021. [DOI: 10.1016/j.tma.2021.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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19
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Liang S, Ezerskyte M, Wang J, Pelechano V, Dreij K. Transcriptional mutagenesis dramatically alters genome-wide p53 transactivation landscape. Sci Rep 2020; 10:13513. [PMID: 32782319 PMCID: PMC7419513 DOI: 10.1038/s41598-020-70412-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 07/27/2020] [Indexed: 11/29/2022] Open
Abstract
The transcriptional error rate can be significantly increased by the presence of DNA lesions that instruct mis-insertion during transcription; a process referred to as transcriptional mutagenesis (TM) that can result in altered protein function. Herein, we determined the effect of O6-methylguanine (O6-meG) on transcription and subsequent transactivation activity of p53 in human lung H1299 cells. Levels of TM and effects on transactivation were determined genome wide by RNA-seq. Results showed that 47% of all p53 transcripts contained an uridine misincorporation opposite the lesion at 6 h post transfection, which was decreased to 18% at 24 h. TM at these levels reduced DNA binding activity of p53 to 21% and 80% compared to wild type p53, respectively. Gene expression data were analysed to identify differentially expressed genes due to TM of p53. We show a temporal repression of transactivation of > 100 high confidence p53 target genes including regulators of the cell cycle, DNA damage response and apoptosis. In addition, TM repressed the transcriptional downregulation by p53 of several negative regulators of proliferation and differentiation. Our work demonstrates that TM, even when restricting its effect to an individual transcription factor, has the potential to alter gene expression programs and diversify cellular phenotypes.
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Affiliation(s)
- Shuo Liang
- Unit of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Monika Ezerskyte
- Unit of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
| | - Jingwen Wang
- Science for Life Laboratory, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Vicent Pelechano
- Science for Life Laboratory, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Kristian Dreij
- Unit of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
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20
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Agapov A, Ignatov A, Turtola M, Belogurov G, Esyunina D, Kulbachinskiy A. Role of the trigger loop in translesion RNA synthesis by bacterial RNA polymerase. J Biol Chem 2020; 295:9583-9595. [PMID: 32439804 DOI: 10.1074/jbc.ra119.011844] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 05/20/2020] [Indexed: 11/06/2022] Open
Abstract
DNA lesions can severely compromise transcription and block RNA synthesis by RNA polymerase (RNAP), leading to subsequent recruitment of DNA repair factors to the stalled transcription complex. Recent structural studies have uncovered molecular interactions of several DNA lesions within the transcription elongation complex. However, little is known about the role of key elements of the RNAP active site in translesion transcription. Here, using recombinantly expressed proteins, in vitro transcription, kinetic analyses, and in vivo cell viability assays, we report that point amino acid substitutions in the trigger loop, a flexible element of the active site involved in nucleotide addition, can stimulate translesion RNA synthesis by Escherichia coli RNAP without altering the fidelity of nucleotide incorporation. We show that these substitutions also decrease transcriptional pausing and strongly affect the nucleotide addition cycle of RNAP by increasing the rate of nucleotide addition but also decreasing the rate of translocation. The secondary channel factors DksA and GreA modulated translesion transcription by RNAP, depending on changes in the trigger loop structure. We observed that although the mutant RNAPs stimulate translesion synthesis, their expression is toxic in vivo, especially under stress conditions. We conclude that the efficiency of translesion transcription can be significantly modulated by mutations affecting the conformational dynamics of the active site of RNAP, with potential effects on cellular stress responses and survival.
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Affiliation(s)
- Aleksei Agapov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Artem Ignatov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Matti Turtola
- Department of Biochemistry, University of Turku, Turku, Finland
| | | | - Daria Esyunina
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
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21
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Franklin A, Steele EJ, Lindley RA. A proposed reverse transcription mechanism for (CAG)n and similar expandable repeats that cause neurological and other diseases. Heliyon 2020; 6:e03258. [PMID: 32140575 PMCID: PMC7044655 DOI: 10.1016/j.heliyon.2020.e03258] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 09/26/2019] [Accepted: 01/15/2020] [Indexed: 12/12/2022] Open
Abstract
The mechanism of (CAG)n repeat generation, and related expandable repeat diseases in non-dividing cells, is currently understood in terms of a DNA template-based DNA repair synthesis process involving hairpin stabilized slippage, local error-prone repair via MutSβ (MSH2-MSH3) hairpin protective stabilization, then nascent strand extension by DNA polymerases-β and -δ. We advance a very similar slipped hairpin-stabilized model involving MSH2-MSH3 with two key differences: the copying template may also be the nascent pre-mRNA with the repair pathway being mediated by the Y-family error-prone enzymes DNA polymerase-η and DNA polymerase-κ acting as reverse transcriptases. We argue that both DNA-based and RNA-based mechanisms could well be activated in affected non-dividing brain cells in vivo. Here, we compare the advantages of the RNA/RT-based model proposed by us as an adjunct to previously proposed models. In brief, our model depends upon dysregulated innate and adaptive immunity cascades involving AID/APOBEC and ADAR deaminases that are known to be involved in normal locus-specific immunoglobulin somatic hypermutation, cancer progression and somatic mutations at many off-target non-immunoglobulin sites across the genome: we explain how these processes could also play an active role in repeat expansion diseases at RNA polymerase II-transcribed genes.
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Affiliation(s)
- Andrew Franklin
- Medical Department, Novartis Pharmaceuticals UK Limited, 200 Frimley Business Park, Frimley, Surrey, GU16 7SR, United Kingdom
| | - Edward J. Steele
- Melville Analytics Pty Ltd, Melbourne, Vic, 3004, Australia
- CYO’Connor ERADE Village Foundation, Perth, WA, Australia
| | - Robyn A. Lindley
- GMDxgenomics, Melbourne, Vic, Australia
- Department of Clinical Pathology, Faculty of Medicine, Dentistry & Health Sciences, University of Melbourne, Vic, Australia
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22
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Giorgio M, Dellino GI, Gambino V, Roda N, Pelicci PG. On the epigenetic role of guanosine oxidation. Redox Biol 2020; 29:101398. [PMID: 31926624 PMCID: PMC6926346 DOI: 10.1016/j.redox.2019.101398] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/23/2019] [Accepted: 12/02/2019] [Indexed: 01/14/2023] Open
Abstract
Chemical modifications of DNA and RNA regulate genome functions or trigger mutagenesis resulting in aging or cancer. Oxidations of macromolecules, including DNA, are common reactions in biological systems and often part of regulatory circuits rather than accidental events. DNA alterations are particularly relevant since the unique role of nuclear and mitochondrial genome is coding enduring and inheritable information. Therefore, an alteration in DNA may represent a relevant problem given its transmission to daughter cells. At the same time, the regulation of gene expression allows cells to continuously adapt to the environmental changes that occur throughout the life of the organism to ultimately maintain cellular homeostasis. Here we review the multiple ways that lead to DNA oxidation and the regulation of mechanisms activated by cells to repair this damage. Moreover, we present the recent evidence suggesting that DNA damage caused by physiological metabolism acts as epigenetic signal for regulation of gene expression. In particular, the predisposition of guanine to oxidation might reflect an adaptation to improve the genome plasticity to redox changes.
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Affiliation(s)
- Marco Giorgio
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy; Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.
| | - Gaetano Ivan Dellino
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Valentina Gambino
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy
| | - Niccolo' Roda
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy
| | - Pier Giuseppe Pelicci
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
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23
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Kitsera N, Rodriguez-Alvarez M, Emmert S, Carell T, Khobta A. Nucleotide excision repair of abasic DNA lesions. Nucleic Acids Res 2019; 47:8537-8547. [PMID: 31226203 PMCID: PMC6895268 DOI: 10.1093/nar/gkz558] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/28/2019] [Accepted: 06/18/2019] [Indexed: 01/05/2023] Open
Abstract
Apurinic/apyrimidinic (AP) sites are a class of highly mutagenic and toxic DNA lesions arising in the genome from a number of exogenous and endogenous sources. Repair of AP lesions takes place predominantly by the base excision pathway (BER). However, among chemically heterogeneous AP lesions formed in DNA, some are resistant to the endonuclease APE1 and thus refractory to BER. Here, we employed two types of reporter constructs accommodating synthetic APE1-resistant AP lesions to investigate the auxiliary repair mechanisms in human cells. By combined analyses of recovery of the transcription rate and suppression of transcriptional mutagenesis at specifically positioned AP lesions, we demonstrate that nucleotide excision repair pathway (NER) efficiently removes BER-resistant AP lesions and significantly enhances the repair of APE1-sensitive ones. Our results further indicate that core NER components XPA and XPF are equally required and that both global genome (GG-NER) and transcription coupled (TC-NER) subpathways contribute to the repair.
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Affiliation(s)
- Nataliya Kitsera
- Unit "Responses to DNA Lesions", Institute of Toxicology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz 55131, Germany
| | - Marta Rodriguez-Alvarez
- Unit "Responses to DNA Lesions", Institute of Toxicology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz 55131, Germany
| | - Steffen Emmert
- Clinic and Policlinic for Dermatology and Venereology, University Medical Center Rostock, Rostock 18057, Germany
| | - Thomas Carell
- Center for Integrated Protein Science at the Department of Chemistry, Ludwig-Maximilians-Universität München, Munich 81377, Germany
| | - Andriy Khobta
- Unit "Responses to DNA Lesions", Institute of Toxicology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz 55131, Germany
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Transcriptional Fidelity of Mitochondrial RNA Polymerase RpoTm from Arabidopsis thaliana. J Mol Biol 2019; 431:4767-4783. [PMID: 31626802 DOI: 10.1016/j.jmb.2019.08.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 05/30/2019] [Accepted: 08/26/2019] [Indexed: 11/21/2022]
Abstract
Fidelity of RNA synthesis is essential for the faithful transfer of information from DNA to RNA. A comprehensive analysis of the nucleotide selectivity by the mitochondrial RNA polymerase (RNAP) RpoTm, from Arabidopsis thaliana, has been carried out. The kinetic parameters for the incorporation of cognate, noncognate, and oxidized bases have been determined. The results establish high fidelity of mitochondrial transcription resembling those of replicative polymerases in the absence of repair. In addition, RpoTm incorporates oxidized nucleotides with similar efficiency compared with mismatches and is capable of extending the RNA beyond the insertion of the oxidized base. Furthermore, lesion bypass study on RpoTm demonstrates that the enzyme bypasses 8-oxo-guanine by insertion of adenine leading to C to A mutations in RNA. Homology modeling of RpoTm elongation complex allows delineation of the residues necessary for stabilizing the incoming NTP substrate and for posing the template nucleotide residue. Substitution of these residues leads to compromise in the activity of the enzyme corroborating their importance in RNA synthesis. Comparison of the data with T7 RNAPs indicates that low efficiency of misincorporation is a universal strategy used by single-subunit RNAPs for maintaining high fidelity in the absence of proofreading and repair activity in mitochondria.
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25
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Steele EJ, Gorczynski RM, Lindley RA, Liu Y, Temple R, Tokoro G, Wickramasinghe DT, Wickramasinghe NC. Lamarck and Panspermia - On the Efficient Spread of Living Systems Throughout the Cosmos. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 149:10-32. [PMID: 31445944 DOI: 10.1016/j.pbiomolbio.2019.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 08/14/2019] [Accepted: 08/21/2019] [Indexed: 02/06/2023]
Abstract
We review the main lines of evidence (molecular, cellular and whole organism) published since the 1970s demonstrating Lamarckian Inheritance in animals, plants and microorganisms viz. the transgenerational inheritance of environmentally-induced acquired characteristics. The studies in animals demonstrate the genetic permeability of the soma-germline Weismann Barrier. The widespread nature of environmentally-directed inheritance phenomena reviewed here contradicts a key pillar of neo-Darwinism which affirms the rigidity of the Weismann Barrier. These developments suggest that neo-Darwinian evolutionary theory is in need of significant revision. We argue that Lamarckian inheritance strategies involving environmentally-induced rapid directional genetic adaptations make biological sense in the context of cosmic Panspermia allowing the efficient spread of living systems and genetic innovation throughout the Universe. The Hoyle-Wickramasinghe Panspermia paradigm also developed since the 1970s, unlike strictly geocentric neo-Darwinism provides a cogent biological rationale for the actual widespread existence of Lamarckian modes of inheritance - it provides its raison d'être. Under a terrestrially confined neo-Darwinian viewpoint such an association may have been thought spurious in the past. Our aim is to outline the conceptual links between rapid Lamarckian-based evolutionary hypermutation processes dependent on reverse transcription-coupled mechanisms among others and the effective cosmic spread of living systems. For example, a viable, or cryo-preserved, living system travelling through space in a protective matrix will need of necessity to rapidly adapt and proliferate on landing in a new cosmic niche. Lamarckian mechanisms thus come to the fore and supersede the slow (blind and random) genetic processes expected under a traditional neo-Darwinian evolutionary paradigm.
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Affiliation(s)
- Edward J Steele
- C.Y.O'Connor ERADE Village Foundation, Piara Waters, Perth, 6112, WA, Australia; Centre for Astrobiology, University of Ruhuna, Matara, Sri Lanka; Melville Analytics Pty Ltd, Melbourne, Vic, Australia.
| | | | - Robyn A Lindley
- Department of Clinical Pathology, Faculty of Medicine, Dentistry & Health Sciences, University of MelbourneVic, Australia; GMDx Group Ltd, Melbourne, Vic, Australia
| | - Yongsheng Liu
- Henan Collaborative Innovation Center of Modern Biological Breeding, Henan Institute of Science and Technology, Xinxiang, 453003, China
| | - Robert Temple
- The History of Chinese Science and Culture Foundation, Conway Hall, London, UK
| | - Gensuke Tokoro
- Centre for Astrobiology, University of Ruhuna, Matara, Sri Lanka; Institute for the Study of Panspermia and Astrobiology, Gifu, Japan
| | - Dayal T Wickramasinghe
- Centre for Astrobiology, University of Ruhuna, Matara, Sri Lanka; College of Physical and Mathematical Sciences, Australian National University, Canberra, Australia
| | - N Chandra Wickramasinghe
- Centre for Astrobiology, University of Ruhuna, Matara, Sri Lanka; Institute for the Study of Panspermia and Astrobiology, Gifu, Japan; Buckingham Centre for Astrobiology, University of Buckingham, UK
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26
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Agapov A, Esyunina D, Kulbachinskiy A. Gre-family factors modulate DNA damage sensing by Deinococcus radiodurans RNA polymerase. RNA Biol 2019; 16:1711-1720. [PMID: 31416390 DOI: 10.1080/15476286.2019.1656027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Deinococcus radiodurans is a highly stress resistant bacterium that encodes universal as well as lineage-specific factors involved in DNA transcription and repair. However, the effects of DNA lesions on RNA synthesis by D. radiodurans RNA polymerase (RNAP) have never been studied. We investigated the ability of this RNAP to transcribe damaged DNA templates and demonstrated that various lesions significantly affect the efficiency and fidelity of RNA synthesis. DNA modifications that disrupt correct base-pairing can strongly inhibit transcription and increase nucleotide misincorporation by D. radiodurans RNAP. The universal transcription factor GreA and Deinococcus-specific factor Gfh1 stimulate RNAP stalling at various DNA lesions, depending on the type of the lesion and the presence of Mn2+ ions, abundant divalent cations in D. radiodurans. Furthermore, Gfh1 stimulates the action of the Mfd translocase, which removes transcription elongation complexes paused at the sites of DNA lesions. Thus, Gre-family factors in D. radiodurans might have evolved to increase the efficiency of DNA damage recognition by the transcription and repair machineries in this bacterium.
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Affiliation(s)
- Aleksei Agapov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Daria Esyunina
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
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AID, APOBEC3A and APOBEC3B efficiently deaminate deoxycytidines neighboring DNA damage induced by oxidation or alkylation. Biochim Biophys Acta Gen Subj 2019; 1863:129415. [PMID: 31404619 DOI: 10.1016/j.bbagen.2019.129415] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 07/26/2019] [Accepted: 08/07/2019] [Indexed: 12/29/2022]
Abstract
BACKGROUND AID/APOBEC3 (A3) enzymes instigate genomic mutations that are involved in immunity and cancer. Although they can deaminate any deoxycytidine (dC) to deoxyuridine (dU), each family member has a signature preference determined by nucleotides surrounding the target dC. This WRC (W = A/T, R = A/G) and YC (Y = T/C) hotspot preference is established for AID and A3A/A3B, respectively. Base alkylation and oxidation are two of the most common types of DNA damage induced environmentally or by chemotherapy. Here we examined the activity of AID, A3A and A3B on dCs neighboring such damaged bases. METHODS Substrates were designed to contain target dCs either in normal WRC/YC hotspots, or in oxidized/alkylated DNA motifs. AID, A3A and A3B were purified and deamination kinetics of each were compared between substrates containing damaged vs. normal motifs. RESULTS All three enzymes efficiently deaminated dC when common damaged bases were present in the -2 or -1 positions. Strikingly, some damaged motifs supported comparable or higher catalytic efficiencies by AID, A3A and A3B than the WRC/YC motifs which are their most favored normal sequences. Based on the resolved interactions of AID, A3A and A3B with DNA, we modeled interactions with alkylated or oxidized bases. Corroborating the enzyme assay data, the surface regions that recognize normal bases are predicted to also interact robustly with oxidized and alkylated bases. CONCLUSIONS AID, A3A and A3B can efficiently recognize and deaminate dC whose neighbouring nucleotides are damaged. GENERAL SIGNIFICANCE Beyond AID/A3s initiating DNA damage, some forms of pre-existing damaged DNA can constitute favored targets of AID/A3s if encountered.
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28
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DNA mismatch repair is required for the host innate response and controls cellular fate after influenza virus infection. Nat Microbiol 2019; 4:1964-1977. [PMID: 31358986 PMCID: PMC6814535 DOI: 10.1038/s41564-019-0509-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 06/07/2019] [Indexed: 02/07/2023]
Abstract
Despite the cytopathic nature of influenza A virus (IAV) replication, we
recently reported that a subset of lung epithelial club cells is able to
intrinsically clear virus and survive infection. However, the mechanisms that
drive cell survival during a normally lytic infection remained unclear. Using a
loss-of-function screening approach, we discovered that the DNA mismatch repair
(MMR) pathway is essential for club cell survival of IAV infection. Repair of
virally-induced oxidative damage by the DNA MMR pathway not only allowed cell
survival of infection but also facilitated host gene transcription, including
the expression of antiviral and stress response genes. Enhanced viral
suppression of the DNA MMR pathway prevented club cell survival and increased
the severity of viral disease in vivo. Altogether, these
results identify previously unappreciated roles for DNA MMR as a central
modulator of cellular fate and a contributor to the innate antiviral response,
which together, control influenza viral disease severity.
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29
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Slyskova J, Sabatella M, Ribeiro-Silva C, Stok C, Theil AF, Vermeulen W, Lans H. Base and nucleotide excision repair facilitate resolution of platinum drugs-induced transcription blockage. Nucleic Acids Res 2019; 46:9537-9549. [PMID: 30137419 PMCID: PMC6182164 DOI: 10.1093/nar/gky764] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/20/2018] [Indexed: 12/21/2022] Open
Abstract
Sensitivity and resistance of cells to platinum drug chemotherapy are to a large extent determined by activity of the DNA damage response (DDR). Combining chemotherapy with inhibition of specific DDR pathways could therefore improve treatment efficacy. Multiple DDR pathways have been implicated in removal of platinum-DNA lesions, but it is unclear which exact pathways are most important to cellular platinum drug resistance. Here, we used CRISPR/Cas9 screening to identify DDR proteins that protect colorectal cancer cells against the clinically applied platinum drug oxaliplatin. We find that besides the expected homologous recombination, Fanconi anemia and translesion synthesis pathways, in particular also transcription-coupled nucleotide excision repair (TC-NER) and base excision repair (BER) protect against platinum-induced cytotoxicity. Both repair pathways are required to overcome oxaliplatin- and cisplatin-induced transcription arrest. In addition to the generation of DNA crosslinks, exposure to platinum drugs leads to reactive oxygen species production that induces oxidative DNA lesions, explaining the requirement for BER. Our findings highlight the importance of transcriptional integrity in cells exposed to platinum drugs and suggest that both TC-NER and BER should be considered as targets for novel combinatorial treatment strategies.
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Affiliation(s)
- Jana Slyskova
- Department of Molecular Genetics, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
| | - Mariangela Sabatella
- Department of Molecular Genetics, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
| | - Cristina Ribeiro-Silva
- Department of Molecular Genetics, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
- Oncode Institute, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
| | - Colin Stok
- Department of Molecular Genetics, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
| | - Arjan F Theil
- Department of Molecular Genetics, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
- Oncode Institute, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
| | - Wim Vermeulen
- Department of Molecular Genetics, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
- Oncode Institute, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
| | - Hannes Lans
- Department of Molecular Genetics, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
- Oncode Institute, Erasmus MC, Erasmus University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands
- To whom correspondence should be addressed. Tel: +31 10 7038169; Fax: +31 10 7044743;
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Cui J, Gizzi A, Stivers JT. Deoxyuridine in DNA has an inhibitory and promutagenic effect on RNA transcription by diverse RNA polymerases. Nucleic Acids Res 2019; 47:4153-4168. [PMID: 30892639 PMCID: PMC6486633 DOI: 10.1093/nar/gkz183] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/04/2019] [Accepted: 03/09/2019] [Indexed: 12/16/2022] Open
Abstract
dUTP is a close structural congener of dTTP and can be readily incorporated into DNA opposite to adenine during DNA replication leading to non-mutagenic dU/A base pairs ('uracilation'). We find that dU/A pairs located within DNA transcriptional templates optimized for either T7 RNA polymerase (T7 RNAP) or human RNA polymerase II (pol II) have inhibitory and mutagenic effects on transcription. The data for T7 RNAP establishes that even a single dU/A pair can inhibit promoter binding and transcription initiation up to 30-fold, and that inhibitory effects on transcription elongation are also possible. Sequencing of the mRNA transcribed from uniformly uracilated DNA templates by T7 RNAP indicated an increased frequency of transversion and insertion mutations compared to all T/A templates. Strong effects of dU/A pairs on cellular transcription activity and fidelity were also observed with RNA pol II using uracil base excision repair (UBER)-deficient human cells. At the highest levels of template uracilation, transcription by RNA pol II was completely blocked. We propose that these effects arise from the decreased thermodynamic stability and increased dynamics of dU/A pairs in DNA. The potential implications of these findings on gene regulation and disease are discussed.
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Affiliation(s)
- Junru Cui
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205-2185, USA
| | - Anthony Gizzi
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205-2185, USA
| | - James T Stivers
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205-2185, USA
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Rho-dependent transcription termination in bacteria recycles RNA polymerases stalled at DNA lesions. Nat Commun 2019; 10:1207. [PMID: 30872584 PMCID: PMC6418286 DOI: 10.1038/s41467-019-09146-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 02/14/2019] [Indexed: 01/25/2023] Open
Abstract
In bacteria, transcription-coupled repair of DNA lesions initiates after the Mfd protein removes RNA polymerases (RNAPs) stalled at the lesions. The bacterial RNA helicase, Rho, is a transcription termination protein that dislodges the elongation complexes. Here, we show that Rho dislodges the stalled RNAPs at DNA lesions. Strains defective in both Rho and Mfd are susceptible to DNA-damaging agents and are inefficient in repairing or propagating UV-damaged DNA. In vitro transcription assays show that Rho dissociates the stalled elongation complexes at the DNA lesions. We conclude that Rho-dependent termination recycles stalled RNAPs, which might facilitate DNA repair and other DNA-dependent processes essential for bacterial cell survival. We surmise that Rho might compete with, or augment, the Mfd function. In bacteria, the Rho protein dislodges elongation complexes to terminate transcription, and the Mfd protein removes RNA polymerases (RNAPs) stalled at DNA lesions. Here, Jain et al. show that Rho also dissociates stalled RNAPs at DNA lesions, which may facilitate DNA repair and other DNA-dependent processes.
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32
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Konovalov KA, Pardo-Avila F, Tse CKM, Oh J, Wang D, Huang X. 8-Oxo-guanine DNA damage induces transcription errors by escaping two distinct fidelity control checkpoints of RNA polymerase II. J Biol Chem 2019; 294:4924-4933. [PMID: 30718278 DOI: 10.1074/jbc.ra118.007333] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 01/29/2019] [Indexed: 01/05/2023] Open
Abstract
RNA polymerase II (Pol II) has an intrinsic fidelity control mechanism to maintain faithful genetic information transfer during transcription. 8-Oxo-guanine (8OG), a commonly occurring damaged guanine base, promotes misincorporation of adenine into the RNA strand. Recent structural work has shown that adenine can pair with the syn conformation of 8OG directly upstream of the Pol II active site. However, it remains unknown how 8OG is accommodated in the active site as a template base for the incoming ATP. Here, we used molecular dynamics (MD) simulations to investigate two consecutive steps that may contribute to the adenine misincorporation by Pol II. First, the mismatch is located in the active site, contributing to initial incorporation of adenine. Second, the mismatch is in the adjacent upstream position, contributing to extension from the mismatched bp. These results are supported by an in vitro transcription assay, confirming that 8OG can induce adenine misincorporation. Our simulations further suggest that 8OG forms a stable bp with the mismatched adenine in both the active site and the adjacent upstream position. This stability predominantly originates from hydrogen bonding between the mismatched adenine and 8OG in a noncanonical syn conformation. Interestingly, we also found that an unstable bp present directly upstream of the active site, such as adenine paired with 8OG in the canonical anti conformation, largely disrupts the stability of the active site. Our findings have uncovered two main factors contributing to how 8OG induces transcriptional errors and escapes Pol II transcriptional fidelity control checkpoints.
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Affiliation(s)
- Kirill A Konovalov
- From the HKUST-Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen 518057, China.,Department of Chemistry, Center of Systems Biology and Human Health, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, and
| | - Fátima Pardo-Avila
- Department of Chemistry, Center of Systems Biology and Human Health, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, and
| | - Carmen Ka Man Tse
- Department of Chemistry, Center of Systems Biology and Human Health, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, and
| | - Juntaek Oh
- Department of Cellular and Molecular Medicine, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093
| | - Dong Wang
- Department of Cellular and Molecular Medicine, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093
| | - Xuhui Huang
- From the HKUST-Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen 518057, China, .,Department of Chemistry, Center of Systems Biology and Human Health, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, and
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Pupov D, Ignatov A, Agapov A, Kulbachinskiy A. Distinct effects of DNA lesions on RNA synthesis by Escherichia coli RNA polymerase. Biochem Biophys Res Commun 2019; 510:122-127. [PMID: 30665719 DOI: 10.1016/j.bbrc.2019.01.062] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 01/12/2019] [Indexed: 01/08/2023]
Abstract
DNA lesions can severely compromise genome stability and lead to cell death if unrepaired. RNA polymerase (RNAP) is known to serve as a sensor of DNA damage and to attract DNA repair factors to the damaged template sites. Here, we systematically investigated the ability of Escherichia coli RNAP to transcribe DNA templates containing various types of DNA lesions, and analyzed their effects on transcription fidelity. We showed that transcription is strongly inhibited on templates containing cyclobutane thymine dimers, 1,N6-ethenoadenine and abasic sites, while 8-oxoguanine and thymine glycol have mild effects on transcription efficiency. Similarly to many polymerases, E. coli RNAP follows the "A" rule during nucleotide insertion opposite abasic sites and bulky lesions, and can also incorporate and efficiently extend an adenine nucleotide opposite 8-oxoguanine. Mutations in RNAP regions around the templating nucleotide decrease the efficiency of translesion synthesis, likely by altering the RNAP-template contacts in the active site. Thus, DNA lesions can lead to distinct outcomes in transcription, depending on the severity of the damage and contacts of the damaged template with the active site of RNAP.
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Affiliation(s)
- Danil Pupov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia
| | - Artem Ignatov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia
| | - Aleksei Agapov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia
| | - Andrey Kulbachinskiy
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia.
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Abstract
Base excision repair (BER) is one of the most active DNA repair pathways in cells correcting DNA damage from oxidation, deamination, alkylation, and damages induced by free radicals and ionizing radiation. Deregulation or deficiencies in BER mechanisms increase the level of mutations leading to carcinogenesis, and single-strand DNA break formation, which may be converted to double-strand breaks and induce apoptosis. BER deficiency is associated with development of diseases causing neurodegenerative disorders, such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). In addition, BER mechanisms can be affected by viral infections, such as HPV, HTLV-1, and HIV-1. Deficiencies in DNA repair in cells can be analyzed using a very convenient and effective approach, where mammalian cells are transfected with plasmids carrying a reporter gene of fluorescent protein that contain inactivating damages. The repair of DNA damages depends on the cellular machinery and is reflected by expression of the reporter gene measured by flow cytometry. In this chapter, we describe this plasmid-based reporter gene system to investigate in cell the repairs of DNA damages involving BER mechanisms.
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Affiliation(s)
- Dorota Piekna-Przybylska
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA.
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35
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Baptiste BA, Katchur SR, Fivenson EM, Croteau DL, Rumsey WL, Bohr VA. Enhanced mitochondrial DNA repair of the common disease-associated variant, Ser326Cys, of hOGG1 through small molecule intervention. Free Radic Biol Med 2018; 124:149-162. [PMID: 29879444 PMCID: PMC6098717 DOI: 10.1016/j.freeradbiomed.2018.05.094] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/30/2018] [Accepted: 05/31/2018] [Indexed: 12/22/2022]
Abstract
The common oxidatively generated lesion, 8-oxo-7,8-dihydroguanine (8-oxoGua), is removed from DNA by base excision repair. The glycosylase primarily charged with recognition and removal of this lesion is 8-oxoGuaDNA glycosylase 1 (OGG1). When left unrepaired, 8-oxodG alters transcription and is mutagenic. Individuals homozygous for the less active OGG1 allele, Ser326Cys, have increased risk of several cancers. Here, small molecule enhancers of OGG1 were identified and tested for their ability to stimulate DNA repair and protect cells from the environmental hazard paraquat (PQ). PQ-induced mtDNA damage was inversely proportional to the levels of OGG1 expression whereas stimulation of OGG1, in some cases, entirely abolished its cellular effects. The PQ-mediated decline of mitochondrial membrane potential or nuclear condensation were prevented by the OGG1 activators. In addition, in Ogg1-/- mouse embryonic fibroblasts complemented with hOGG1S326C, there was increased cellular and mitochondrial reactive oxygen species compared to their wild type counterparts. Mitochondrial extracts from cells expressing hOGG1S326C were deficient in mitochondrial 8-oxodG incision activity, which was rescued by the OGG1 activators. These data demonstrate that small molecules can stimulate OGG1 activity with consequent cellular protection. Thus, OGG1-activating compounds may be useful in select humans to mitigate the deleterious effects of environmental oxidants and mutagens.
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Affiliation(s)
- Beverly A Baptiste
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Steven R Katchur
- Respiratory Therapy Area, GSK R&D, Collegeville, PA, United States
| | - Elayne M Fivenson
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Deborah L Croteau
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - William L Rumsey
- Respiratory Therapy Area, GSK R&D, Collegeville, PA, United States
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States.
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36
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Steele EJ. Reverse Transcriptase Mechanism of Somatic Hypermutation: 60 Years of Clonal Selection Theory. Front Immunol 2017; 8:1611. [PMID: 29218047 PMCID: PMC5704389 DOI: 10.3389/fimmu.2017.01611] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 11/07/2017] [Indexed: 01/24/2023] Open
Abstract
The evidence for the reverse transcriptase mechanism of somatic hypermutation is substantial and multifactorial. In this 60th anniversary year of the publication of Sir MacFarlane Burnet's Clonal Selection Theory, the evidence is briefly reviewed and updated.
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Affiliation(s)
- Edward J. Steele
- CYO’Connor ERADE Village Foundation Inc., Piara Waters, WA, Australia
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37
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In vivo measurements of interindividual differences in DNA glycosylases and APE1 activities. Proc Natl Acad Sci U S A 2017; 114:E10379-E10388. [PMID: 29122935 DOI: 10.1073/pnas.1712032114] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The integrity of our DNA is challenged with at least 100,000 lesions per cell on a daily basis. Failure to repair DNA damage efficiently can lead to cancer, immunodeficiency, and neurodegenerative disease. Base excision repair (BER) recognizes and repairs minimally helix-distorting DNA base lesions induced by both endogenous and exogenous DNA damaging agents. Levels of BER-initiating DNA glycosylases can vary between individuals, suggesting that quantitating and understanding interindividual differences in DNA repair capacity (DRC) may enable us to predict and prevent disease in a personalized manner. However, population studies of BER capacity have been limited because most methods used to measure BER activity are cumbersome, time consuming and, for the most part, only allow for the analysis of one DNA glycosylase at a time. We have developed a fluorescence-based multiplex flow-cytometric host cell reactivation assay wherein the activity of several enzymes [four BER-initiating DNA glycosylases and the downstream processing apurinic/apyrimidinic endonuclease 1 (APE1)] can be tested simultaneously, at single-cell resolution, in vivo. Taking advantage of the transcriptional properties of several DNA lesions, we have engineered specific fluorescent reporter plasmids for quantitative measurements of 8-oxoguanine DNA glycosylase, alkyl-adenine DNA glycosylase, MutY DNA glycosylase, uracil DNA glycosylase, and APE1 activity. We have used these reporters to measure differences in BER capacity across a panel of cell lines collected from healthy individuals, and to generate mathematical models that predict cellular sensitivity to methylmethane sulfonate, H2O2, and 5-FU from DRC. Moreover, we demonstrate the suitability of these reporters to measure differences in DRC in multiple pathways using primary lymphocytes from two individuals.
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38
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Abstract
Transcription elongation is not uniform and transcription is often hindered by protein-bound factors or DNA lesions that limit translocation and impair catalysis. Despite the high degree of sequence and structural homology of the multi-subunit RNA polymerases (RNAP), substantial differences in response to DNA lesions have been reported. Archaea encode only a single RNAP with striking structural conservation with eukaryotic RNAP II (Pol II). Here, we demonstrate that the archaeal RNAP from Thermococcus kodakarensis is sensitive to a variety of DNA lesions that pause and arrest RNAP at or adjacent to the site of DNA damage. DNA damage only halts elongation when present in the template strand, and the damage often results in RNAP arresting such that the lesion would be encapsulated with the transcription elongation complex. The strand-specific halt to archaeal transcription elongation on modified templates is supportive of RNAP recognizing DNA damage and potentially initiating DNA repair through a process akin to the well-described transcription-coupled DNA repair (TCR) pathways in Bacteria and Eukarya.
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Affiliation(s)
- Alexandra M Gehring
- a Department of Biochemistry and Molecular Biology , Colorado State University , Fort Collins , CO , USA.,b Institute for Genome Architecture and Function, Colorado State University , Fort Collins , CO , USA
| | - Thomas J Santangelo
- a Department of Biochemistry and Molecular Biology , Colorado State University , Fort Collins , CO , USA.,b Institute for Genome Architecture and Function, Colorado State University , Fort Collins , CO , USA
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Kolbanovskiy M, Chowdhury MA, Nadkarni A, Broyde S, Geacintov NE, Scicchitano DA, Shafirovich V. The Nonbulky DNA Lesions Spiroiminodihydantoin and 5-Guanidinohydantoin Significantly Block Human RNA Polymerase II Elongation in Vitro. Biochemistry 2017; 56:3008-3018. [PMID: 28514164 DOI: 10.1021/acs.biochem.7b00295] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The most common, oxidatively generated lesion in cellular DNA is 8-oxo-7,8-dihydroguanine, which can be oxidized further to yield highly mutagenic spiroiminodihydantoin (Sp) and 5-guanidinohydantoin (Gh) in DNA. In human cell-free extracts, both lesions can be excised by base excision repair and global genomic nucleotide excision repair. However, it is not known if these lesions can be removed by transcription-coupled DNA repair (TCR), a pathway that clears lesions from DNA that impede RNA synthesis. To determine if Sp or Gh impedes transcription, which could make each a viable substrate for TCR, either an Sp or a Gh lesion was positioned on the transcribed strand of DNA under the control of a promoter that supports transcription by human RNA polymerase II. These constructs were incubated in HeLa nuclear extracts that contained active RNA polymerase II, and the resulting transcripts were resolved by denaturing polyacrylamide gel electrophoresis. The structurally rigid Sp strongly blocks transcription elongation, permitting 1.6 ± 0.5% nominal lesion bypass. In contrast, the conformationally flexible Gh poses less of a block to human RNAPII, allowing 9 ± 2% bypass. Furthermore, fractional lesion bypass for Sp and Gh is minimally affected by glycosylase activity found in the HeLa nuclear extract. These data specifically suggest that both Sp and Gh may well be susceptible to TCR because each poses a significant block to human RNA polymerase II progression. A more general principle is also proposed: Conformational flexibility may be an important structural feature of DNA lesions that enhances their transcriptional bypass.
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Affiliation(s)
- Marina Kolbanovskiy
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003-5180, United States
| | - Moinuddin A Chowdhury
- Department of Biology, New York University , 100 Washington Square East, New York, New York 10003-5180, United States
| | - Aditi Nadkarni
- Department of Biology, New York University , 100 Washington Square East, New York, New York 10003-5180, United States
| | - Suse Broyde
- Department of Biology, New York University , 100 Washington Square East, New York, New York 10003-5180, United States
| | - Nicholas E Geacintov
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003-5180, United States
| | - David A Scicchitano
- Department of Biology, New York University , 100 Washington Square East, New York, New York 10003-5180, United States.,Division of Science, New York University Abu Dhabi , P.O. Box 129188, Abu Dhabi, United Arab Emirates
| | - Vladimir Shafirovich
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003-5180, United States
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40
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Menoni H, Di Mascio P, Cadet J, Dimitrov S, Angelov D. Chromatin associated mechanisms in base excision repair - nucleosome remodeling and DNA transcription, two key players. Free Radic Biol Med 2017; 107:159-169. [PMID: 28011149 DOI: 10.1016/j.freeradbiomed.2016.12.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 12/13/2016] [Accepted: 12/19/2016] [Indexed: 12/30/2022]
Abstract
Genomic DNA is prone to a large number of insults by a myriad of endogenous and exogenous agents. The base excision repair (BER) is the major mechanism used by cells for the removal of various DNA lesions spontaneously or environmentally induced and the maintenance of genome integrity. The presence of persistent DNA damage is not compatible with life, since abrogation of BER leads to early embryonic lethality in mice. There are several lines of evidences showing existence of a link between deficient BER, cancer proneness and ageing, thus illustrating the importance of this DNA repair pathway in human health. Although the enzymology of BER mechanisms has been largely elucidated using chemically defined DNA damage substrates and purified proteins, the complex interplay of BER with another vital process like transcription or when DNA is in its natural state (i.e. wrapped in nucleosome and assembled in chromatin fiber is largely unexplored. Cells use chromatin remodeling factors to overcome the general repression associated with the nucleosomal organization. It is broadly accepted that energy-dependent nucleosome remodeling factors disrupt histones-DNA interactions at the expense of ATP hydrolysis to favor transcription as well as DNA repair. Importantly, unlike transcription, BER is not part of a regulated developmental process but represents a maintenance system that should be efficient anytime and anywhere in the genome. In this review we will discuss how BER can deal with chromatin organization to maintain genetic information. Emphasis will be placed on the following challenging question: how BER is initiated within chromatin?
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Affiliation(s)
- Hervé Menoni
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL UMR 5239 and Institut NeuroMyoGène - INMG CNRS/UCBL UMR 5310, Université de Lyon, Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université de Grenoble Alpes/INSERM U1209/CNRS UMR 5309, 38042 Grenoble Cedex 9, France.
| | - Paolo Di Mascio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, CP 26077, CEP 05508-000 São Paulo, SP, Brazil
| | - Jean Cadet
- Département de Médecine Nucléaire et de Radiobiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada J1H 5N4
| | - Stefan Dimitrov
- Université de Grenoble Alpes/INSERM U1209/CNRS UMR 5309, 38042 Grenoble Cedex 9, France
| | - Dimitar Angelov
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL UMR 5239 and Institut NeuroMyoGène - INMG CNRS/UCBL UMR 5310, Université de Lyon, Ecole Normale Supérieure de Lyon, 69007 Lyon, France.
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41
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Steele EJ, Lindley RA. ADAR deaminase A-to-I editing of DNA and RNA moieties of RNA:DNA hybrids has implications for the mechanism of Ig somatic hypermutation. DNA Repair (Amst) 2017; 55:1-6. [PMID: 28482199 DOI: 10.1016/j.dnarep.2017.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 04/14/2017] [Accepted: 04/14/2017] [Indexed: 11/16/2022]
Abstract
The implications are discussed of recently published biochemical studies on ADAR-mediated A-to-I DNA and RNA deamination at RNA:DNA hybrids. The significance of these data are related to previous work on strand-biased and codon-context mutation signatures in B lymphocytes and cancer genomes. Those studies have established that there are two significant strand biases at A:T and G:C base pairs, A-site mutations exceed T-site mutations (A>>T) by 2.9 fold and G-site mutations exceed C-site mutations (G>>C) by 1.7 fold. Both these strand biases are inconsistent with alternative "DNA Deamination" mechanisms, yet are expected consequences of the RNA/RT-based "Reverse Transcriptase" mechanism of immunoglobulin (Ig) somatic hypermutation (SHM). The A-to-I DNA editing component at RNA:DNA hybrids that is likely to occur in Transcription Bubbles, while important, is of far lower A-to-I editing efficiency than in dsRNA substrates. The RNA moiety of RNA:DNA hybrids is also edited at similar lower frequencies relative to the editing rate at dsRNA substrates. Further, if the A-to-I DNA editing at RNA:DNA hybrids were the sole cause of A-to-I (read as A-to-G) mutation events for Ig SHM in vivo then the exact opposite strand biases at A:T base pairs (T>>A) of what is actually observed (A>>T) would be predicted. It is concluded that the strand-biased somatic mutation patterns at both A:T and G:C base pairs in vivo are best interpreted by the sequential steps of the RNA/RT-based mechanism. Further, the direct DNA A-to-I deamination at Transcription Bubbles is expected to contribute to the T-to-C component of the strand-biased Ig SHM spectrum.
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Affiliation(s)
- Edward J Steele
- CYO'Connor ERADE Village Foundation Inc., Piara Waters, WA, Australia.
| | - Robyn A Lindley
- GMDxCo Pty Ltd., Hawthorn Vic, Australia; Department of Pathology, Faculty of Medicine, Dentistry & Health Sciences, University of Melbourne Vic, Australia
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42
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Weihe P, Debes F, Halling J, Petersen MS, Muckle G, Odland JØ, Dudarev A, Ayotte P, Dewailly É, Grandjean P, Bonefeld-Jørgensen E. Health effects associated with measured levels of contaminants in the Arctic. Int J Circumpolar Health 2016; 75:33805. [PMID: 27974137 PMCID: PMC5156856 DOI: 10.3402/ijch.v75.33805] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The Human Health Assessment Group has over the past decade recommended that effect studies be conducted in the circumpolar area. Such studies examine the association between contaminant exposure in the Arctic populations and health effects. Because foetuses and young children are the most vulnerable, effect studies are often prospective child cohort studies. The emphasis in this article is on a description of the effects associated with contaminant exposure in the Arctic. The main topics addressed are neurobehavioural, immunological, reproductive, cardiovascular, endocrine and carcinogenic effect. For each topic, the association between exposure and effects is described, and some results are reported for similar studies outside the Arctic.
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Affiliation(s)
- Pál Weihe
- Department of Occupational Medicine and Public Health, The Faroese Hospital System, Torshavn, Faroe Islands;
| | - Fróði Debes
- Department of Occupational Medicine and Public Health, The Faroese Hospital System, Torshavn, Faroe Islands
| | - Jónrit Halling
- Department of Occupational Medicine and Public Health, The Faroese Hospital System, Torshavn, Faroe Islands
| | - Maria Skaalum Petersen
- Department of Occupational Medicine and Public Health, The Faroese Hospital System, Torshavn, Faroe Islands
| | - Gina Muckle
- École de psychologie, Université Laval and Centre de recherche du CHU de Québec, Québec, City, QC, Canada
| | - Jon Øyvind Odland
- Department of Community Medicine, UiT The Arctic University of Norway, Tromso, Norway
| | - Alexey Dudarev
- Northwest Public Health Research Center, St. Petersburg, Russia
| | | | | | - Philippe Grandjean
- Department of Environmental Medicine, Univerisity of Southern Denmark, Odense, Denmark
| | - Eva Bonefeld-Jørgensen
- Centre for Arctic Health, Department of Public Health, Aarhus University, Aarhus, Denmark
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43
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Yu Y, Cui Y, Niedernhofer LJ, Wang Y. Occurrence, Biological Consequences, and Human Health Relevance of Oxidative Stress-Induced DNA Damage. Chem Res Toxicol 2016; 29:2008-2039. [PMID: 27989142 DOI: 10.1021/acs.chemrestox.6b00265] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A variety of endogenous and exogenous agents can induce DNA damage and lead to genomic instability. Reactive oxygen species (ROS), an important class of DNA damaging agents, are constantly generated in cells as a consequence of endogenous metabolism, infection/inflammation, and/or exposure to environmental toxicants. A wide array of DNA lesions can be induced by ROS directly, including single-nucleobase lesions, tandem lesions, and hypochlorous acid (HOCl)/hypobromous acid (HOBr)-derived DNA adducts. ROS can also lead to lipid peroxidation, whose byproducts can also react with DNA to produce exocyclic DNA lesions. A combination of bioanalytical chemistry, synthetic organic chemistry, and molecular biology approaches have provided significant insights into the occurrence, repair, and biological consequences of oxidatively induced DNA lesions. The involvement of these lesions in the etiology of human diseases and aging was also investigated in the past several decades, suggesting that the oxidatively induced DNA adducts, especially bulky DNA lesions, may serve as biomarkers for exploring the role of oxidative stress in human diseases. The continuing development and improvement of LC-MS/MS coupled with the stable isotope-dilution method for DNA adduct quantification will further promote research about the clinical implications and diagnostic applications of oxidatively induced DNA adducts.
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Affiliation(s)
| | | | - Laura J Niedernhofer
- Department of Metabolism and Aging, The Scripps Research Institute Florida , Jupiter, Florida 33458, United States
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44
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Hansen EC, Ransom M, Hesselberth JR, Hosmane NN, Capoferri AA, Bruner KM, Pollack RA, Zhang H, Drummond MB, Siliciano JM, Siliciano R, Stivers JT. Diverse fates of uracilated HIV-1 DNA during infection of myeloid lineage cells. eLife 2016; 5. [PMID: 27644592 PMCID: PMC5030084 DOI: 10.7554/elife.18447] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 08/23/2016] [Indexed: 12/22/2022] Open
Abstract
We report that a major subpopulation of monocyte-derived macrophages (MDMs) contains high levels of dUTP, which is incorporated into HIV-1 DNA during reverse transcription (U/A pairs), resulting in pre-integration restriction and post-integration mutagenesis. After entering the nucleus, uracilated viral DNA products are degraded by the uracil base excision repair (UBER) machinery with less than 1% of the uracilated DNA successfully integrating. Although uracilated proviral DNA showed few mutations, the viral genomic RNA was highly mutated, suggesting that errors occur during transcription. Viral DNA isolated from blood monocytes and alveolar macrophages (but not T cells) of drug-suppressed HIV-infected individuals also contained abundant uracils. The presence of viral uracils in short-lived monocytes suggests their recent infection through contact with virus producing cells in a tissue reservoir. These findings reveal new elements of a viral defense mechanism involving host UBER that may be relevant to the establishment and persistence of HIV-1 infection. DOI:http://dx.doi.org/10.7554/eLife.18447.001 Human immunodeficiency virus type 1 (HIV-1) infects and kills immune cells known as CD4+ T cells, leading to the disease AIDS. Current drug treatments enable HIV-1 infected patients to live relatively long and healthy lives. However, no cure for HIV-1 exists because the virus lives indefinitely in a resting state within the genetic material – or genome – of the infected cell, where it is not susceptible to drug treatments. Most HIV-1 research focuses on T cells, but another type of immune cell – the macrophage – may also harbor resting HIV-1 in its genome. Compared to other cells, macrophages are unusual because they produce large amounts of a molecule called deoxyuridine triphosphate (dUTP). Most cells, including T cells, keep dUTP levels very low because it closely resembles molecules that are used to make DNA and so it can be accidentally incorporated into the cell’s DNA. When this happens, the cell removes the dUTP from the DNA using enzymes in a process called uracil base excision repair (UBER). To hide inside the cell’s genome, HIV-1 needs to produce a DNA copy of its own genome, but it was not known what happens when HIV-1 tries to do this within a macrophage that contains high levels of dUTP and UBER enzymes. Here, Hansen et al. reveal that about 90% of macrophages have exceptionally high levels of dUTP and are poorly infected by HIV-1. The high levels of dUTP result in the virus incorporating dUTP into its DNA, which is then attacked and fragmented by UBER enzymes. However, about one in a hundred viral DNA molecules do manage to successfully integrate into the genome of the macrophage. This viral DNA later gives rise to new virus particles through an error-prone process that, by introducing new mutations into the virus genome, may help HIV-1 to evolve and persist. Further experiments examined cells that give rise to macrophages from infected patients who had been on anti-HIV drug therapy for several years. Hansen et al. found that there was lots of dUTP in the DNA sequences of HIV-1 viruses found in these “precursor” cells. These precursor cells only live for several days before being eliminated, so the presence of viruses containing dUTP suggests these cells were infected recently. A future challenge will be to identify new anti-HIV drugs that specifically target macrophages and to understand the role of error-prone production of new viral genomes. DOI:http://dx.doi.org/10.7554/eLife.18447.002
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Affiliation(s)
- Erik C Hansen
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Monica Ransom
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, United States
| | - Jay R Hesselberth
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, United States
| | - Nina N Hosmane
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Adam A Capoferri
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, The Johns Hopkins School of Medicine, Baltimore, United States
| | - Katherine M Bruner
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Ross A Pollack
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Hao Zhang
- W Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
| | - Michael Bradley Drummond
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Janet M Siliciano
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Robert Siliciano
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, The Johns Hopkins School of Medicine, Baltimore, United States
| | - James T Stivers
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
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45
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Somatic hypermutation in immunity and cancer: Critical analysis of strand-biased and codon-context mutation signatures. DNA Repair (Amst) 2016; 45:1-24. [DOI: 10.1016/j.dnarep.2016.07.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 07/01/2016] [Indexed: 01/01/2023]
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46
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Ranes M, Boeing S, Wang Y, Wienholz F, Menoni H, Walker J, Encheva V, Chakravarty P, Mari PO, Stewart A, Giglia-Mari G, Snijders AP, Vermeulen W, Svejstrup JQ. A ubiquitylation site in Cockayne syndrome B required for repair of oxidative DNA damage, but not for transcription-coupled nucleotide excision repair. Nucleic Acids Res 2016; 44:5246-55. [PMID: 27060134 PMCID: PMC4914099 DOI: 10.1093/nar/gkw216] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 02/11/2016] [Accepted: 03/18/2016] [Indexed: 12/23/2022] Open
Abstract
Cockayne syndrome B (CSB), best known for its role in transcription-coupled nucleotide excision repair (TC-NER), contains a ubiquitin-binding domain (UBD), but the functional connection between protein ubiquitylation and this UBD remains unclear. Here, we show that CSB is regulated via site-specific ubiquitylation. Mass spectrometry analysis of CSB identified lysine (K) 991 as a ubiquitylation site. Intriguingly, mutation of this residue (K991R) does not affect CSB's catalytic activity or protein stability, but greatly affects genome stability, even in the absence of induced DNA damage. Moreover, cells expressing CSB K991R are sensitive to oxidative DNA damage, but proficient for TC-NER. K991 becomes ubiquitylated upon oxidative DNA damage, and while CSB K991R is recruited normally to such damage, it fails to dissociate in a timely manner, suggesting a requirement for K991 ubiquitylation in CSB activation. Interestingly, deletion of CSB's UBD gives rise to oxidative damage sensitivity as well, while CSB ΔUBD and CSB K991R affects expression of overlapping groups of genes, further indicating a functional connection. Together, these results shed new light on the regulation of CSB, with K991R representing an important separation-of-function-mutation in this multi-functional protein.
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Affiliation(s)
- Michael Ranes
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, Clare Hall Laboratories, South Mimms EN6 3LD, UK
| | - Stefan Boeing
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, Clare Hall Laboratories, South Mimms EN6 3LD, UK
| | - Yuming Wang
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, Clare Hall Laboratories, South Mimms EN6 3LD, UK
| | - Franziska Wienholz
- Department of Genetics, Cancer Genomics Netherlands, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, Netherlands
| | - Hervé Menoni
- Department of Genetics, Cancer Genomics Netherlands, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, Netherlands
| | - Jane Walker
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, Clare Hall Laboratories, South Mimms EN6 3LD, UK
| | - Vesela Encheva
- Protein Analysis and Proteomics Laboratory, The Francis Crick Institute, Clare Hall Laboratories, South Mimms EN6 3LD, UK
| | - Probir Chakravarty
- Bioinformatics & Biostatistics Laboratory, The Francis Crick Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Pierre-Olivier Mari
- Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, F-31077 Toulouse, France
| | - Aengus Stewart
- Bioinformatics & Biostatistics Laboratory, The Francis Crick Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Giuseppina Giglia-Mari
- Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, F-31077 Toulouse, France
| | - Ambrosius P Snijders
- Protein Analysis and Proteomics Laboratory, The Francis Crick Institute, Clare Hall Laboratories, South Mimms EN6 3LD, UK
| | - Wim Vermeulen
- Department of Genetics, Cancer Genomics Netherlands, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, Netherlands
| | - Jesper Q Svejstrup
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, Clare Hall Laboratories, South Mimms EN6 3LD, UK
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47
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hSSB1 (NABP2/OBFC2B) is regulated by oxidative stress. Sci Rep 2016; 6:27446. [PMID: 27273218 PMCID: PMC4897654 DOI: 10.1038/srep27446] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/18/2016] [Indexed: 12/17/2022] Open
Abstract
The maintenance of genome stability is an essential cellular process to prevent the development of diseases including cancer. hSSB1 (NABP2/ OBFC2A) is a critical component of the DNA damage response where it participates in the repair of double-strand DNA breaks and in base excision repair of oxidized guanine residues (8-oxoguanine) by aiding the localization of the human 8-oxoguanine glycosylase (hOGG1) to damaged DNA. Here we demonstrate that following oxidative stress, hSSB1 is stabilized as an oligomer which is required for hSSB1 to function in the removal of 8-oxoguanine. Monomeric hSSB1 shows a decreased affinity for oxidized DNA resulting in a cellular 8-oxoguanine-repair defect and in the absence of ATM signaling initiation. While hSSB1 oligomerization is important for the removal of 8-oxoguanine from the genome, it is not required for the repair of double-strand DNA-breaks by homologous recombination. These findings demonstrate a novel hSSB1 regulatory mechanism for the repair of damaged DNA.
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48
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Goljanek-Whysall K, Iwanejko LA, Vasilaki A, Pekovic-Vaughan V, McDonagh B. Ageing in relation to skeletal muscle dysfunction: redox homoeostasis to regulation of gene expression. Mamm Genome 2016; 27:341-57. [PMID: 27215643 PMCID: PMC4935741 DOI: 10.1007/s00335-016-9643-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/05/2016] [Indexed: 12/17/2022]
Abstract
Ageing is associated with a progressive loss of skeletal muscle mass, quality and function—sarcopenia, associated with reduced independence and quality of life in older generations. A better understanding of the mechanisms, both genetic and epigenetic, underlying this process would help develop therapeutic interventions to prevent, slow down or reverse muscle wasting associated with ageing. Currently, exercise is the only known effective intervention to delay the progression of sarcopenia. The cellular responses that occur in muscle fibres following exercise provide valuable clues to the molecular mechanisms regulating muscle homoeostasis and potentially the progression of sarcopenia. Redox signalling, as a result of endogenous generation of ROS/RNS in response to muscle contractions, has been identified as a crucial regulator for the adaptive responses to exercise, highlighting the redox environment as a potentially core therapeutic approach to maintain muscle homoeostasis during ageing. Further novel and attractive candidates include the manipulation of microRNA expression. MicroRNAs are potent gene regulators involved in the control of healthy and disease-associated biological processes and their therapeutic potential has been researched in the context of various disorders, including ageing-associated muscle wasting. Finally, we discuss the impact of the circadian clock on the regulation of gene expression in skeletal muscle and whether disruption of the peripheral muscle clock affects sarcopenia and altered responses to exercise. Interventions that include modifying altered redox signalling with age and incorporating genetic mechanisms such as circadian- and microRNA-based gene regulation, may offer potential effective treatments against age-associated sarcopenia.
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Affiliation(s)
- Katarzyna Goljanek-Whysall
- MRC-Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8XL, UK.
| | - Lesley A Iwanejko
- MRC-Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8XL, UK
| | - Aphrodite Vasilaki
- MRC-Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8XL, UK
| | - Vanja Pekovic-Vaughan
- MRC-Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8XL, UK
| | - Brian McDonagh
- MRC-Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8XL, UK.
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49
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Raindlová V, Janoušková M, Slavíčková M, Perlíková P, Boháčová S, Milisavljevič N, Šanderová H, Benda M, Barvík I, Krásný L, Hocek M. Influence of major-groove chemical modifications of DNA on transcription by bacterial RNA polymerases. Nucleic Acids Res 2016; 44:3000-12. [PMID: 27001521 PMCID: PMC4838386 DOI: 10.1093/nar/gkw171] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 03/04/2016] [Indexed: 12/11/2022] Open
Abstract
DNA templates containing a set of base modifications in the major groove (5-substituted pyrimidines or 7-substituted 7-deazapurines bearing H, methyl, vinyl, ethynyl or phenyl groups) were prepared by PCR using the corresponding base-modified 2′-deoxyribonucleoside triphosphates (dNTPs). The modified templates were used in an in vitro transcription assay using RNA polymerase from Bacillus subtilis and Escherichia coli. Some modified nucleobases bearing smaller modifications (H, Me in 7-deazapurines) were perfectly tolerated by both enzymes, whereas bulky modifications (Ph at any nucleobase) and, surprisingly, uracil blocked transcription. Some middle-sized modifications (vinyl or ethynyl) were partly tolerated mostly by the E. coli enzyme. In all cases where the transcription proceeded, full length RNA product with correct sequence was obtained indicating that the modifications of the template are not mutagenic and the inhibition is probably at the stage of initiation. The results are promising for the development of bioorthogonal reactions for artificial chemical switching of the transcription.
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Affiliation(s)
- Veronika Raindlová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Gilead & IOCB Research Center, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic
| | - Martina Janoušková
- Department of Molecular Genetics of Bacteria, Institute of Microbiology, Academy of Sciences of the Czech Republic, CZ-14220 Prague 4, Czech Republic
| | - Michaela Slavíčková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Gilead & IOCB Research Center, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic
| | - Pavla Perlíková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Gilead & IOCB Research Center, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic
| | - Soňa Boháčová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Gilead & IOCB Research Center, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic
| | - Nemanja Milisavljevič
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Gilead & IOCB Research Center, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic
| | - Hana Šanderová
- Department of Molecular Genetics of Bacteria, Institute of Microbiology, Academy of Sciences of the Czech Republic, CZ-14220 Prague 4, Czech Republic
| | - Martin Benda
- Department of Molecular Genetics of Bacteria, Institute of Microbiology, Academy of Sciences of the Czech Republic, CZ-14220 Prague 4, Czech Republic
| | - Ivan Barvík
- Division of Biomolecular Physics, Institute of Physics, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2, Czech Republic
| | - Libor Krásný
- Department of Molecular Genetics of Bacteria, Institute of Microbiology, Academy of Sciences of the Czech Republic, CZ-14220 Prague 4, Czech Republic
| | - Michal Hocek
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Gilead & IOCB Research Center, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 8, CZ-12843 Prague 2, Czech Republic
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50
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Sanchez JR, Reddick TL, Perez M, Centonze VE, Mitra S, Izumi T, McMahan CA, Walter CA. Increased human AP endonuclease 1 level confers protection against the paternal age effect in mice. Mutat Res 2015; 779:124-33. [PMID: 26201249 PMCID: PMC4554949 DOI: 10.1016/j.mrfmmm.2015.06.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 06/12/2015] [Accepted: 06/17/2015] [Indexed: 11/27/2022]
Abstract
Increased paternal age is associated with a greater risk of producing children with genetic disorders originating from de novo germline mutations. Mice mimic the human condition by displaying an age-associated increase in spontaneous mutant frequency in spermatogenic cells. The observed increase in mutant frequency appears to be associated with a decrease in the DNA repair protein, AP endonuclease 1 (APEX1) and Apex1 heterozygous mice display an accelerated paternal age effect as young adults. In this study, we directly tested if APEX1 over-expression in cell lines and transgenic mice could prevent increases in mutagenesis. Cell lines with ectopic expression of APEX1 had increased APEX1 activity and lower spontaneous and induced mutations in the lacI reporter gene relative to the control. Spermatogenic cells obtained from mice transgenic for human APEX1 displayed increased APEX1 activity, were protected from the age-dependent increase in spontaneous germline mutagenesis, and exhibited increased apoptosis in the spermatogonial cell population. These results directly indicate that increases in APEX1 level confer protection against the murine paternal age effect, thus highlighting the role of APEX1 in preserving reproductive health with increasing age and in protection against genotoxin-induced mutagenesis in somatic cells.
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Affiliation(s)
- Jamila R Sanchez
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX 78229, USA
| | - Traci L Reddick
- Duke Cancer Institute, Duke University, 20 Duke Medicine Circle, Durham, NC 27710, USA
| | - Marissa Perez
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX 78229, USA
| | - Victoria E Centonze
- Cell & Tissue Imaging Center, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Sankar Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, 6550 Fannin Street, Houston, TX 77030, USA
| | - Tadahide Izumi
- Graduate Center for Toxicology, 1095 V.A. Drive, Lexington, KY 40536, USA
| | - C Alex McMahan
- Department of Pathology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX 78229, USA
| | - Christi A Walter
- South Texas Veteran's Health Care System, 7400 Merton Minter Blvd., San Antonio, TX 78229, USA; Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX 78229, USA; Cancer Therapy & Research Center, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX 78229, USA; Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX 78229, USA.
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