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Boldinova EO, Baranovskiy AG, Filina YV, Miftakhova RR, Shamsutdinova YF, Tahirov TH, Makarova AV. PrimPol Variant V102A with Altered Primase and Polymerase Activities. J Mol Biol 2024; 436:168542. [PMID: 38492718 DOI: 10.1016/j.jmb.2024.168542] [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: 01/05/2024] [Revised: 03/10/2024] [Accepted: 03/12/2024] [Indexed: 03/18/2024]
Abstract
PrimPol is a human DNA primase-polymerase which restarts DNA synthesis beyond DNA lesions and non-B DNA structures blocking replication. Disfunction of PrimPol in cells leads to slowing of DNA replication rates in mitochondria and nucleus, accumulation of chromosome aberrations, cell cycle delay, and elevated sensitivity to DNA-damaging agents. A defective PrimPol has been suggested to be associated with the development of ophthalmic diseases, elevated mitochondrial toxicity of antiviral drugs and increased cell resistance to chemotherapy. Here, we describe a rare missense PrimPol variant V102A with altered biochemical properties identified in patients suffering from ovarian and cervical cancer. The Val102 to Ala substitution dramatically reduced both the primase and DNA polymerase activities of PrimPol as well as specifically decreased its ability to incorporate ribonucleotides. Structural analysis indicates that the V102A substitution can destabilize the hydrophobic pocket adjacent to the active site, affecting dNTP binding and catalysis.
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Affiliation(s)
- Elizaveta O Boldinova
- National Research Center "Kurchatov Institute", Kurchatov sq. 2, 123182 Moscow, Russia; Institute of Gene Biology, Russian Academy of Sciences, Vavilova 34 / 5, 119334 Moscow, Russia
| | - Andrey G Baranovskiy
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Yulia V Filina
- "Translational Oncology" Research Laboratory, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia
| | - Regina R Miftakhova
- "Translational Oncology" Research Laboratory, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia
| | - Yana F Shamsutdinova
- Chemotherapy Department №1, Republican Clinical Oncology Dispensary of the Ministry of Health of the Republic of Tatarstan Named After Prof. M.Z. Sigal, Sibirskiy trakt 29, 420029 Kazan, Russia
| | - Tahir H Tahirov
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Alena V Makarova
- National Research Center "Kurchatov Institute", Kurchatov sq. 2, 123182 Moscow, Russia; Institute of Gene Biology, Russian Academy of Sciences, Vavilova 34 / 5, 119334 Moscow, Russia.
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2
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Mellor C, Nassar J, Šviković S, Sale J. PRIMPOL ensures robust handoff between on-the-fly and post-replicative DNA lesion bypass. Nucleic Acids Res 2024; 52:243-258. [PMID: 37971291 PMCID: PMC10783524 DOI: 10.1093/nar/gkad1054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/17/2023] [Accepted: 10/24/2023] [Indexed: 11/19/2023] Open
Abstract
The primase/polymerase PRIMPOL restarts DNA synthesis when replication is arrested by template impediments. However, we do not have a comprehensive view of how PRIMPOL-dependent repriming integrates with the main pathways of damage tolerance, REV1-dependent 'on-the-fly' lesion bypass at the fork and PCNA ubiquitination-dependent post-replicative gap filling. Guided by genome-wide CRISPR/Cas9 screens to survey the genetic interactions of PRIMPOL in a non-transformed and p53-proficient human cell line, we find that PRIMPOL is needed for cell survival following loss of the Y-family polymerases REV1 and POLη in a lesion-dependent manner, while it plays a broader role in promoting survival of cells lacking PCNA K164-dependent post-replicative gap filling. Thus, while REV1- and PCNA K164R-bypass provide two layers of protection to ensure effective damage tolerance, PRIMPOL is required to maximise the effectiveness of the interaction between them. We propose this is through the restriction of post-replicative gap length provided by PRIMPOL-dependent repriming.
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Affiliation(s)
- Christopher Mellor
- Division of Protein & Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Joelle Nassar
- Division of Protein & Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Saša Šviković
- Division of Protein & Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Julian E Sale
- Division of Protein & Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
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3
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Duardo RC, Guerra F, Pepe S, Capranico G. Non-B DNA structures as a booster of genome instability. Biochimie 2023; 214:176-192. [PMID: 37429410 DOI: 10.1016/j.biochi.2023.07.002] [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: 03/29/2023] [Revised: 07/04/2023] [Accepted: 07/06/2023] [Indexed: 07/12/2023]
Abstract
Non-canonical secondary structures (NCSs) are alternative nucleic acid structures that differ from the canonical B-DNA conformation. NCSs often occur in repetitive DNA sequences and can adopt different conformations depending on the sequence. The majority of these structures form in the context of physiological processes, such as transcription-associated R-loops, G4s, as well as hairpins and slipped-strand DNA, whose formation can be dependent on DNA replication. It is therefore not surprising that NCSs play important roles in the regulation of key biological processes. In the last years, increasing published data have supported their biological role thanks to genome-wide studies and the development of bioinformatic prediction tools. Data have also highlighted the pathological role of these secondary structures. Indeed, the alteration or stabilization of NCSs can cause the impairment of transcription and DNA replication, modification in chromatin structure and DNA damage. These events lead to a wide range of recombination events, deletions, mutations and chromosomal aberrations, well-known hallmarks of genome instability which are strongly associated with human diseases. In this review, we summarize molecular processes through which NCSs trigger genome instability, with a focus on G-quadruplex, i-motif, R-loop, Z-DNA, hairpin, cruciform and multi-stranded structures known as triplexes.
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Affiliation(s)
- Renée C Duardo
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126, Bologna, Italy
| | - Federico Guerra
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126, Bologna, Italy
| | - Simona Pepe
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126, Bologna, Italy
| | - Giovanni Capranico
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126, Bologna, Italy.
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4
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Gromova AS, Boldinova EO, Kim DV, Chuprov-Netochin RN, Leonov SV, Pustovalova MV, Zharkov DO, Makarova AV. Response of PRIMPOL-Knockout Human Lung Adenocarcinoma A549 Cells to Genotoxic Stress. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:1933-1943. [PMID: 38105210 DOI: 10.1134/s0006297923110214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 08/08/2023] [Accepted: 09/15/2023] [Indexed: 12/19/2023]
Abstract
Human DNA primase/polymerase PrimPol synthesizes DNA primers de novo after replication fork stalling at the sites of DNA damage, thus contributing to the DNA damage tolerance. The role of PrimPol in response to the different types of DNA damage is poorly understood. We knocked out the PRIMPOL gene in the lung carcinoma A549 cell line and characterized the response of the obtained cells to the DNA damage caused by hydrogen peroxide, methyl methanesulfonate (MMS), cisplatin, bleomycin, and ionizing radiation. The PRIMPOL knockout reduced the number of proliferating cells and cells in the G2 phase after treatment with MMS and caused a more pronounced delay of the S phase in the cisplatin-treated cells. Ionizing radiation at a dose of 10 Gy significantly increased the content of apoptotic cells among the PRIMPOL-deficient cells, while the proportion of cells undergoing necroptosis increased in both parental and knockout cells at any radiation dose. The viability of PRIMPOL-deficient cells upon the hydrogen peroxide-induced oxidative stress increased compared to the control cells, as determined by the methyl tetrazolium (MTT) assay. The obtained data indicate the involvement of PRIMPOL in the modulation of adaptive cell response to various types of genotoxic stress.
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Affiliation(s)
- Anastasia S Gromova
- Institute of Molecular Genetics, Kurchatov Institute National Research Center, Moscow, 123182, Russia
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
| | - Elizaveta O Boldinova
- Institute of Molecular Genetics, Kurchatov Institute National Research Center, Moscow, 123182, Russia
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
| | - Daria V Kim
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
- Novosibirsk State University, Novosibirsk, 630090, Russia
| | - Roman N Chuprov-Netochin
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, 141700, Russia
| | - Sergey V Leonov
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, 141700, Russia
- Institute of Cell Biophysics of the Russian Academy of Sciences, Pushchino, 142290, Russia
| | - Margarita V Pustovalova
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, 141700, Russia
| | - Dmitry O Zharkov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.
- Novosibirsk State University, Novosibirsk, 630090, Russia
| | - Alena V Makarova
- Institute of Molecular Genetics, Kurchatov Institute National Research Center, Moscow, 123182, Russia.
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
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Boldinova EO, Baranovskiy AG, Gagarinskaya DI, Manukyan A, Makarova A, Tahirov T. The role of catalytic and regulatory domains of human PrimPol in DNA binding and synthesis. Nucleic Acids Res 2023; 51:7541-7551. [PMID: 37326028 PMCID: PMC10415149 DOI: 10.1093/nar/gkad507] [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: 12/15/2022] [Revised: 04/28/2023] [Accepted: 05/31/2023] [Indexed: 06/17/2023] Open
Abstract
Human PrimPol possesses DNA primase and DNA polymerase activities and restarts stalled replication forks protecting cells against DNA damage in nuclei and mitochondria. The zinc-binding motif (ZnFn) of the C-terminal domain (CTD) of PrimPol is required for DNA primase activity but the mechanism is not clear. In this work, we biochemically demonstrate that PrimPol initiates de novo DNA synthesis in cis-orientation, when the N-terminal catalytic domain (NTD) and the CTD of the same molecule cooperate for substrates binding and catalysis. The modeling studies revealed that PrimPol uses a similar mode of initiating NTP coordination as the human primase. The ZnFn motif residue Arg417 is required for binding the 5'-triphosphate group that stabilizes the PrimPol complex with a DNA template-primer. We found that the NTD alone is able to initiate DNA synthesis, and the CTD stimulates the primase activity of NTD. The regulatory role of the RPA-binding motif in the modulation of PrimPol binding to DNA is also demonstrated.
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Affiliation(s)
- Elizaveta O Boldinova
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Kurchatov sq. 2, 123182 Moscow, Russia
- Institute of Gene Biology, Russian Academy of Sciences, Vavilov 34/5, 119334 Moscow, Russia
| | - Andrey G Baranovskiy
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Diana I Gagarinskaya
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Kurchatov sq. 2, 123182 Moscow, Russia
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Anna A Manukyan
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Kurchatov sq. 2, 123182 Moscow, Russia
- Institute of Gene Biology, Russian Academy of Sciences, Vavilov 34/5, 119334 Moscow, Russia
| | - Alena V Makarova
- Institute of Molecular Genetics, National Research Center "Kurchatov Institute", Kurchatov sq. 2, 123182 Moscow, Russia
- Institute of Gene Biology, Russian Academy of Sciences, Vavilov 34/5, 119334 Moscow, Russia
| | - Tahir H Tahirov
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
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6
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Boldinova EO, Makarova AV. Regulation of Human DNA Primase-Polymerase PrimPol. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:1139-1155. [PMID: 37758313 DOI: 10.1134/s0006297923080084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 10/03/2023]
Abstract
Transmission of genetic information depends on successful completion of DNA replication. Genomic DNA is subjected to damage on a daily basis. DNA lesions create obstacles for DNA polymerases and can lead to the replication blockage, formation of DNA breaks, cell cycle arrest, and apoptosis. Cells have evolutionary adapted to DNA damage by developing mechanisms allowing elimination of lesions prior to DNA replication (DNA repair) and helping to bypass lesions during DNA synthesis (DNA damage tolerance). The second group of mechanisms includes the restart of DNA synthesis at the sites of DNA damage by DNA primase-polymerase PrimPol. Human PrimPol was described in 2013. The properties and functions of this enzyme have been extensively studied in recent years, but very little is known about the regulation of PrimPol and association between the enzyme dysfunction and diseases. In this review, we described the mechanisms of human PrimPol regulation in the context of DNA replication, discussed in detail interactions of PrimPol with other proteins, and proposed possible pathways for the regulation of human PrimPol activity. The article also addresses the association of PrimPol dysfunction with human diseases.
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Affiliation(s)
- Elizaveta O Boldinova
- Kurchatov Institute National Research Centre, Moscow, 123182, Russia.
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
| | - Alena V Makarova
- Kurchatov Institute National Research Centre, Moscow, 123182, Russia
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
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7
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Saldanha J, Rageul J, Patel JA, Kim H. The Adaptive Mechanisms and Checkpoint Responses to a Stressed DNA Replication Fork. Int J Mol Sci 2023; 24:10488. [PMID: 37445667 PMCID: PMC10341514 DOI: 10.3390/ijms241310488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/13/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
DNA replication is a tightly controlled process that ensures the faithful duplication of the genome. However, DNA damage arising from both endogenous and exogenous assaults gives rise to DNA replication stress associated with replication fork slowing or stalling. Therefore, protecting the stressed fork while prompting its recovery to complete DNA replication is critical for safeguarding genomic integrity and cell survival. Specifically, the plasticity of the replication fork in engaging distinct DNA damage tolerance mechanisms, including fork reversal, repriming, and translesion DNA synthesis, enables cells to overcome a variety of replication obstacles. Furthermore, stretches of single-stranded DNA generated upon fork stalling trigger the activation of the ATR kinase, which coordinates the cellular responses to replication stress by stabilizing the replication fork, promoting DNA repair, and controlling cell cycle and replication origin firing. Deregulation of the ATR checkpoint and aberrant levels of chronic replication stress is a common characteristic of cancer and a point of vulnerability being exploited in cancer therapy. Here, we discuss the various adaptive responses of a replication fork to replication stress and the roles of ATR signaling that bring fork stabilization mechanisms together. We also review how this knowledge is being harnessed for the development of checkpoint inhibitors to trigger the replication catastrophe of cancer cells.
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Affiliation(s)
- Joanne Saldanha
- The Graduate Program in Genetics, Stony Brook University, Stony Brook, NY 11794, USA
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Julie Rageul
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Jinal A Patel
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Hyungjin Kim
- The Graduate Program in Genetics, Stony Brook University, Stony Brook, NY 11794, USA
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
- Stony Brook Cancer Center, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA
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8
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Si B, Wang X, Liu Y, Wang J, Zhou Y, Nie Y, Xu A. Multi-locus deletion mutation induced by silver nanoparticles: Role of lysosomal-autophagy dysfunction. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 257:114947. [PMID: 37105094 DOI: 10.1016/j.ecoenv.2023.114947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 04/18/2023] [Accepted: 04/21/2023] [Indexed: 05/08/2023]
Abstract
Due to the rapid production growth and a wide range of applications, safety concerns are being raised about the genotoxic properties of silver nanoparticles (AgNPs). In this research, we found AgNPs induced a size-dependent genotoxicity via lysosomal-autophagy dysfunction in human-hamster hybrid (AL) cells. Compared with 25 nm and 75 nm particles, 5 nm AgNPs could accentuate the genotoxic responses, including DNA double-strand breaks (DSBs) and multi-locus deletion mutation, which could be significantly enhanced by autophagy inhibitors 3-methyl adenine (3-MA), Bafilomycin A1 (BFA), and cathepsin inhibitors, respectively. The autophagy dysfunction was closely related to the accumulation of 5 nm AgNPs in the lysosomes and the interruption of lysosome-autophagosome fusion. With lysosomal protective agent 3-O-Methylsphingomyelin (3-O-M) and endocytosis inhibitor wortmannin, the reactivation of lysosomal function and the recovery of autophagy significantly attenuated AgNP-induced genotoxicity. Our data provide clear evidence to illustrate the role of subcellular targets in the genotoxicity of AgNPs in mammalian cells, which laid the basis for better understanding the health risk of AgNPs and their related products.
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Affiliation(s)
- Bo Si
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, PR China; University of Science and Technology of China, Hefei, Anhui 230026, PR China
| | - Xue Wang
- School of Public Health, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong 250117, PR China
| | - Yun Liu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, PR China
| | - Juan Wang
- Department of Public Health Inspection and Quarantine, School of Public Health, Anhui Medical University, Hefei, Anhui 230032, PR China
| | - Yemian Zhou
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, PR China
| | - Yaguang Nie
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, PR China.
| | - An Xu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, PR China; University of Science and Technology of China, Hefei, Anhui 230026, PR China; Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, PR China.
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9
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Zerbib A, Simon I. Characterization of Unidirectional Replication Forks in the Mouse Genome. Int J Mol Sci 2023; 24:9611. [PMID: 37298562 PMCID: PMC10253849 DOI: 10.3390/ijms24119611] [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: 04/30/2023] [Revised: 05/22/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023] Open
Abstract
Origins of replication are genomic regions in which replication initiates in a bidirectional manner. Recently, a new methodology (origin-derived single-stranded DNA sequencing; ori-SSDS) was developed that allows the detection of replication initiation in a strand-specific manner. Reanalysis of the strand-specific data revealed that 18-33% of the peaks are non-symmetrical, suggesting a single direction of replication. Analysis of replication fork direction data revealed that these are origins of replication in which the replication is paused in one of the directions, probably due to the existence of a replication fork barrier. Analysis of the unidirectional origins revealed a preference of G4 quadruplexes for the blocked leading strand. Taken together, our analysis identified hundreds of genomic locations in which the replication initiates only in one direction, and suggests that G4 quadruplexes may serve as replication fork barriers in such places.
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Affiliation(s)
| | - Itamar Simon
- Department of Microbiology and Molecular Genetics, IMRIC, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem 91120, Israel;
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10
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Di Biagi L, Malacaria E, Aiello FA, Valenzisi P, Marozzi G, Franchitto A, Pichierri P. RAD52 prevents accumulation of Polα-dependent replication gaps at perturbed replication forks in human cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.12.536536. [PMID: 37090680 PMCID: PMC10120653 DOI: 10.1101/2023.04.12.536536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Replication gaps can arise as a consequence of perturbed DNA replication and their accumulation might undermine the stability of the genome. Loss of RAD52, a protein involved in the regulation of fork reversal, promotes accumulation of parental ssDNA gaps during replication perturbation. Here, we demonstrate that this is due to the engagement of Polα downstream of the extensive degradation of perturbed replication forks after their reversal, and is not dependent on PrimPol. Polα is hyper-recruited at parental ssDNA in the absence of RAD52, and this recruitment is dependent on fork reversal enzymes and RAD51. Of note, we report that the interaction between Polα and RAD51 is stimulated by RAD52 inhibition, and Polα-dependent gap accumulation requires nucleation of RAD51 suggesting that it occurs downstream strand invasion. Altogether, our data indicate that RAD51-Polα-dependent repriming is essential to promote fork restart and limit DNA damage accumulation when RAD52 function is disabled.
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Affiliation(s)
- Ludovica Di Biagi
- Mechanisms, Biomarkers and Models Section, Department of Environment and Health, Istituto Superiore di Sanità - Viale Regina Elena 299, 00161 Rome (Italy)
- Istituto Nazionale Biostrutture e Biosistemi - Roma Area Research Unit - Via delle Medaglie d’Oro 305, 00136 Rome (Italy)
| | - Eva Malacaria
- Mechanisms, Biomarkers and Models Section, Department of Environment and Health, Istituto Superiore di Sanità - Viale Regina Elena 299, 00161 Rome (Italy)
| | - Francesca Antonella Aiello
- Mechanisms, Biomarkers and Models Section, Department of Environment and Health, Istituto Superiore di Sanità - Viale Regina Elena 299, 00161 Rome (Italy)
- Istituto Nazionale Biostrutture e Biosistemi - Roma Area Research Unit - Via delle Medaglie d’Oro 305, 00136 Rome (Italy)
| | - Pasquale Valenzisi
- Mechanisms, Biomarkers and Models Section, Department of Environment and Health, Istituto Superiore di Sanità - Viale Regina Elena 299, 00161 Rome (Italy)
| | - Giorgia Marozzi
- Mechanisms, Biomarkers and Models Section, Department of Environment and Health, Istituto Superiore di Sanità - Viale Regina Elena 299, 00161 Rome (Italy)
| | - Annapaola Franchitto
- Mechanisms, Biomarkers and Models Section, Department of Environment and Health, Istituto Superiore di Sanità - Viale Regina Elena 299, 00161 Rome (Italy)
| | - Pietro Pichierri
- Mechanisms, Biomarkers and Models Section, Department of Environment and Health, Istituto Superiore di Sanità - Viale Regina Elena 299, 00161 Rome (Italy)
- Istituto Nazionale Biostrutture e Biosistemi - Roma Area Research Unit - Via delle Medaglie d’Oro 305, 00136 Rome (Italy)
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11
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Abstract
High-fidelity DNA replication is critical for the faithful transmission of genetic information to daughter cells. Following genotoxic stress, specialized DNA damage tolerance pathways are activated to ensure replication fork progression. These pathways include translesion DNA synthesis, template switching and repriming. In this Review, we describe how DNA damage tolerance pathways impact genome stability, their connection with tumorigenesis and their effects on cancer therapy response. We discuss recent findings that single-strand DNA gap accumulation impacts chemoresponse and explore a growing body of evidence that suggests that different DNA damage tolerance factors, including translesion synthesis polymerases, template switching proteins and enzymes affecting single-stranded DNA gaps, represent useful cancer targets. We further outline how the consequences of DNA damage tolerance mechanisms could inform the discovery of new biomarkers to refine cancer therapies.
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Affiliation(s)
- Emily Cybulla
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, USA
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
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12
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Saleem B, Farooq U, Rehman OU, Aqeel M, Farooq MS, Naeem MK, Inam S, Ajmal W, Rahim AA, Chen M, Kalsoom R, Uzair M, Fiaz S, Attia K, Alafari HA, Khan MR, Yu G. Genome-wide and molecular characterization of the DNA replication helicase 2 ( DNA2) gene family in rice under drought and salt stress. Front Genet 2022; 13:1039548. [PMID: 36506305 PMCID: PMC9728955 DOI: 10.3389/fgene.2022.1039548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 10/31/2022] [Indexed: 11/23/2022] Open
Abstract
Rice plants experience various biotic (such as insect and pest attack) and abiotic (such as drought, salt, heat, and cold etc.) stresses during the growing season, resulting in DNA damage and the subsequent losses in rice production. DNA Replication Helicase/Nuclease2 (DNA2) is known to be involved in DNA replication and repair. In animals and yeast DNA2 are well characterized because it has the abilities of both helicase and nuclease, it plays a crucial role in DNA replication in the nucleus and mitochondrial genomes. However; they are not fully examined in plants due to less focused on plants damage repair. To fill this research gap, the current study focused on the genome-wide identification and characterization of OsDNA2 genes, along with analyses of their transcriptional expression, duplication, and phylogeny in rice. Overall, 17 OsDNA2 members were reported to be found on eight different chromosomes (2, 3, 4, 6, 7, 9, 10, and 11). Among these chromosomes (Chr), Chr4 contained a maximum of six OsDNA2 genes. Based on phylogenetic analysis, the OsDNA2 gene members were clustered into three different groups. Furthermore, the conserved domains, gene structures, and cis-regulatory elements were systematically investigated. Gene duplication analysis revealed that OsDNA2_2 had an evolutionary relationship with OsDNA2_14, OsDNA2_5 with OsDNA2_6, and OsDNA2_1 with OsDNA2_8. Moreover, results showed that the conserved domain (AAA_11 superfamily) were present in the OsDNA2 genes, which belongs to the DEAD-like helicase superfamily. In addition, to understand the post-transcriptional modification of OsDNA2 genes, miRNAs were predicted, where 653 miRNAs were reported to target 17 OsDNA2 genes. The results indicated that at the maximum, OsDNA2_1 and OsDNA2_4 were targeted by 74 miRNAs each, and OsDNA2_9 was less targeted (20 miRNAs). The three-dimensional (3D) structures of 17 OsDNA2 proteins were also predicted. Expression of OsDNA2 members was also carried out under drought and salt stresses, and conclusively their induction indicated the possible involvement of OsDNA2 in DNA repair under stress when compared with the control. Further studies are recommended to confirm where this study will offer valuable basic data on the functioning of DNA2 genes in rice and other crop plants.
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Affiliation(s)
- Bilal Saleem
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Umer Farooq
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Obaid Ur Rehman
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan,Department of Bioinformatics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Muhammad Aqeel
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Muhammad Shahbaz Farooq
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Muhammad Kashif Naeem
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Safeena Inam
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Wajya Ajmal
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Amna Abdul Rahim
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan
| | - Ming Chen
- Department of Bioinformatics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Rabia Kalsoom
- School of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Muhammad Uzair
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan,National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China,*Correspondence: Muhammad Uzair, ; Muhammad Ramzan Khan, ; Guoping Yu,
| | - Sajid Fiaz
- Department of Plant Breeding and Genetics, The University of Haripur, Haripur, Pakistan
| | - Kotb Attia
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Hayat Ali Alafari
- Department of Biology, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Muhammad Ramzan Khan
- National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Islamabad, Pakistan,*Correspondence: Muhammad Uzair, ; Muhammad Ramzan Khan, ; Guoping Yu,
| | - Guoping Yu
- National Nanfan Research Institute, Chinese Academy of Agricultural Sciences, Sanya, China,China National Rice Research Institute, Hangzhou, China,Hainan Yazhou Bay Seed Lab, Sanya, China,*Correspondence: Muhammad Uzair, ; Muhammad Ramzan Khan, ; Guoping Yu,
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13
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Benureau Y, Pouvelle C, Dupaigne P, Baconnais S, Moreira Tavares E, Mazón G, Despras E, Le Cam E, Kannouche P. Changes in the architecture and abundance of replication intermediates delineate the chronology of DNA damage tolerance pathways at UV-stalled replication forks in human cells. Nucleic Acids Res 2022; 50:9909-9929. [PMID: 36107774 PMCID: PMC9508826 DOI: 10.1093/nar/gkac746] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 08/09/2022] [Accepted: 08/23/2022] [Indexed: 11/21/2022] Open
Abstract
DNA lesions in S phase threaten genome stability. The DNA damage tolerance (DDT) pathways overcome these obstacles and allow completion of DNA synthesis by the use of specialised translesion (TLS) DNA polymerases or through recombination-related processes. However, how these mechanisms coordinate with each other and with bulk replication remains elusive. To address these issues, we monitored the variation of replication intermediate architecture in response to ultraviolet irradiation using transmission electron microscopy. We show that the TLS polymerase η, able to accurately bypass the major UV lesion and mutated in the skin cancer-prone xeroderma pigmentosum variant (XPV) syndrome, acts at the replication fork to resolve uncoupling and prevent post-replicative gap accumulation. Repriming occurs as a compensatory mechanism when this on-the-fly mechanism cannot operate, and is therefore predominant in XPV cells. Interestingly, our data support a recombination-independent function of RAD51 at the replication fork to sustain repriming. Finally, we provide evidence for the post-replicative commitment of recombination in gap repair and for pioneering observations of in vivo recombination intermediates. Altogether, we propose a chronology of UV damage tolerance in human cells that highlights the key role of polη in shaping this response and ensuring the continuity of DNA synthesis.
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Affiliation(s)
- Yann Benureau
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory Genome Integrity , Immune Response and Cancers, Equipe Labellisée La Ligue Contre Le Cancer, Gustave Roussy 94805 , Villejuif , France
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory DSB Repair , Replication stress and Genome Integrity, Gustave Roussy 94805 , Villejuif, France
- Université Paris-Saclay , France
| | - Caroline Pouvelle
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory Genome Integrity , Immune Response and Cancers, Equipe Labellisée La Ligue Contre Le Cancer, Gustave Roussy 94805 , Villejuif , France
- Université Paris-Saclay , France
| | - Pauline Dupaigne
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory DSB Repair , Replication stress and Genome Integrity, Gustave Roussy 94805 , Villejuif, France
- Université Paris-Saclay , France
| | - Sonia Baconnais
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory DSB Repair , Replication stress and Genome Integrity, Gustave Roussy 94805 , Villejuif, France
- Université Paris-Saclay , France
| | - Eliana Moreira Tavares
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory DSB Repair , Replication stress and Genome Integrity, Gustave Roussy 94805 , Villejuif, France
- Université Paris-Saclay , France
| | - Gerard Mazón
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory DSB Repair , Replication stress and Genome Integrity, Gustave Roussy 94805 , Villejuif, France
- Université Paris-Saclay , France
| | - Emmanuelle Despras
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory Genome Integrity , Immune Response and Cancers, Equipe Labellisée La Ligue Contre Le Cancer, Gustave Roussy 94805 , Villejuif , France
- Université Paris-Saclay , France
| | - Eric Le Cam
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory DSB Repair , Replication stress and Genome Integrity, Gustave Roussy 94805 , Villejuif, France
- Université Paris-Saclay , France
| | - Patricia L Kannouche
- UMR9019 CNRS, Genome Integrity and Cancers, Laboratory Genome Integrity , Immune Response and Cancers, Equipe Labellisée La Ligue Contre Le Cancer, Gustave Roussy 94805 , Villejuif , France
- Université Paris-Saclay , France
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14
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APOBEC mutagenesis is low in most types of non-B DNA structures. iScience 2022; 25:104535. [PMID: 35754742 PMCID: PMC9213766 DOI: 10.1016/j.isci.2022.104535] [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: 01/14/2022] [Revised: 04/22/2022] [Accepted: 06/01/2022] [Indexed: 11/22/2022] Open
Abstract
While somatic mutations are known to be enriched in genome regions with non-canonical DNA secondary structure, the impact of particular mutagens still needs to be elucidated. Here, we demonstrate that in human cancers, the APOBEC mutagenesis is not enriched in direct repeats, mirror repeats, short tandem repeats, and G-quadruplexes, and even decreased below its level in B-DNA for cancer samples with very high APOBEC activity. In contrast, we observe that the APOBEC-induced mutational density is positively associated with APOBEC activity in inverted repeats (cruciform structures), where the impact of cytosine at the 3’-end of the hairpin loop is substantial. Surprisingly, the APOBEC-signature mutation density per TC motif in the single-stranded DNA of a G-quadruplex (G4) is lower than in the four-stranded part of G4 and in B-DNA. The APOBEC mutagenesis, as well as the UV-mutagenesis in melanoma samples, are absent in Z-DNA regions, owing to the depletion of their mutational signature motifs. APOBEC mutagenesis is not enriched in most non-canonical DNA structures Inverted repeats (cruciform structures) show increased APOBEC mutagenesis G-quadruplex’s unstructured strand has low APOBEC-induced mutation density Decrease of APOBEC mutagenesis in non-B DNA possibly associated with PrimPol
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15
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Mehta KPM, Thada V, Zhao R, Krishnamoorthy A, Leser M, Lindsey Rose K, Cortez D. CHK1 phosphorylates PRIMPOL to promote replication stress tolerance. SCIENCE ADVANCES 2022; 8:eabm0314. [PMID: 35353580 PMCID: PMC8967226 DOI: 10.1126/sciadv.abm0314] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 02/07/2022] [Indexed: 05/02/2023]
Abstract
Replication-coupled DNA repair and damage tolerance mechanisms overcome replication stress challenges and complete DNA synthesis. These pathways include fork reversal, translesion synthesis, and repriming by specialized polymerases such as PRIMPOL. Here, we investigated how these pathways are used and regulated in response to varying replication stresses. Blocking lagging-strand priming using a POLα inhibitor slows both leading- and lagging-strand synthesis due in part to RAD51-, HLTF-, and ZRANB3-mediated, but SMARCAL1-independent, fork reversal. ATR is activated, but CHK1 signaling is dampened compared to stalling both the leading and lagging strands with hydroxyurea. Increasing CHK1 activation by overexpressing CLASPIN in POLα-inhibited cells promotes replication elongation through PRIMPOL-dependent repriming. CHK1 phosphorylates PRIMPOL to promote repriming irrespective of the type of replication stress, and this phosphorylation is important for cellular resistance to DNA damage. However, PRIMPOL activation comes at the expense of single-strand gap formation, and constitutive PRIMPOL activity results in reduced cell fitness.
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Affiliation(s)
| | - Vaughn Thada
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Runxiang Zhao
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Archana Krishnamoorthy
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Micheal Leser
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Kristie Lindsey Rose
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
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16
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PrimPol: A Breakthrough among DNA Replication Enzymes and a Potential New Target for Cancer Therapy. Biomolecules 2022; 12:biom12020248. [PMID: 35204749 PMCID: PMC8961649 DOI: 10.3390/biom12020248] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/29/2022] [Accepted: 02/02/2022] [Indexed: 02/01/2023] Open
Abstract
DNA replication can encounter blocking obstacles, leading to replication stress and genome instability. There are several mechanisms for evading this blockade. One mechanism consists of repriming ahead of the obstacles, creating a new starting point; in humans, PrimPol is responsible for carrying out this task. PrimPol is a primase that operates in both the nucleus and mitochondria. In contrast with conventional primases, PrimPol is a DNA primase able to initiate DNA synthesis de novo using deoxynucleotides, discriminating against ribonucleotides. In vitro, PrimPol can act as a DNA primase, elongating primers that PrimPol itself sythesizes, or as translesion synthesis (TLS) DNA polymerase, elongating pre-existing primers across lesions. However, the lack of evidence for PrimPol polymerase activity in vivo suggests that PrimPol only acts as a DNA primase. Here, we provide a comprehensive review of human PrimPol covering its biochemical properties and structure, in vivo function and regulation, and the processes that take place to fill the gap-containing lesion that PrimPol leaves behind. Finally, we explore the available data on human PrimPol expression in different tissues in physiological conditions and its role in cancer.
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17
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Bailey LJ, Teague R, Kolesar P, Bainbridge LJ, Lindsay HD, Doherty AJ. PLK1 regulates the PrimPol damage tolerance pathway during the cell cycle. SCIENCE ADVANCES 2021; 7:eabh1004. [PMID: 34860556 PMCID: PMC8641930 DOI: 10.1126/sciadv.abh1004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 10/14/2021] [Indexed: 05/14/2023]
Abstract
Replication stress and DNA damage stall replication forks and impede genome synthesis. During S phase, damage tolerance pathways allow lesion bypass to ensure efficient genome duplication. One such pathway is repriming, mediated by Primase-Polymerase (PrimPol) in human cells. However, the mechanisms by which PrimPol is regulated are poorly understood. Here, we demonstrate that PrimPol is phosphorylated by Polo-like kinase 1 (PLK1) at a conserved residue between PrimPol’s RPA binding motifs. This phosphorylation is differentially modified throughout the cell cycle, which prevents aberrant recruitment of PrimPol to chromatin. Phosphorylation can also be delayed and reversed in response to replication stress. The absence of PLK1-dependent regulation of PrimPol induces phenotypes including chromosome breaks, micronuclei, and decreased survival after treatment with camptothecin, olaparib, and UV-C. Together, these findings establish that deregulated repriming leads to genomic instability, highlighting the importance of regulating this damage tolerance pathway following fork stalling and throughout the cell cycle.
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Affiliation(s)
- Laura J. Bailey
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Rebecca Teague
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Peter Kolesar
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Lewis J. Bainbridge
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Howard D. Lindsay
- Lancaster Medical School, Faculty of Health and Medicine, Lancaster University, Lancaster LA1 4YQ, UK
| | - Aidan J. Doherty
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
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18
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García-Medel PL, Peralta-Castro A, Baruch-Torres N, Fuentes-Pascacio A, Pedroza-García JA, Cruz-Ramirez A, Brieba LG. Arabidopsis thaliana PrimPol is a primase and lesion bypass DNA polymerase with the biochemical characteristics to cope with DNA damage in the nucleus, mitochondria, and chloroplast. Sci Rep 2021; 11:20582. [PMID: 34663822 PMCID: PMC8523556 DOI: 10.1038/s41598-021-00151-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/07/2021] [Indexed: 11/09/2022] Open
Abstract
PrimPol is a novel Primase–Polymerase that synthesizes RNA and DNA primers de novo and extents from these primers as a DNA polymerase. Animal PrimPol is involved in nuclear and mitochondrial DNA replication by virtue of its translesion DNA synthesis (TLS) and repriming activities. Here we report that the plant model Arabidopsis thaliana encodes a functional PrimPol (AtPrimPol). AtPrimPol is a low fidelity and a TLS polymerase capable to bypass DNA lesions, like thymine glycol and abasic sites, by incorporating directly across these lesions or by skipping them. AtPrimPol is also an efficient primase that preferentially recognizes the single-stranded 3′-GTCG-5′ DNA sequence, where the 3′-G is cryptic. AtPrimPol is the first DNA polymerase that localizes in three cellular compartments: nucleus, mitochondria, and chloroplast. In vitro, AtPrimPol synthesizes primers that are extended by the plant organellar DNA polymerases and this reaction is regulated by organellar single-stranded binding proteins. Given the constant exposure of plants to endogenous and exogenous DNA-damaging agents and the enzymatic capabilities of lesion bypass and re-priming of AtPrimPol, we postulate a predominant role of this enzyme in avoiding replication fork collapse in all three plant genomes, both as a primase and as a TLS polymerase.
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Affiliation(s)
- Paola L García-Medel
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, CP 36821, Irapuato, Guanajuato, Mexico
| | - Antolín Peralta-Castro
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, CP 36821, Irapuato, Guanajuato, Mexico
| | - Noe Baruch-Torres
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, CP 36821, Irapuato, Guanajuato, Mexico.,Department of Pharmacology and Toxicology, The University of Texas Medical Branch at Galveston, Galveston, TX, 77555, USA
| | - Alma Fuentes-Pascacio
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, CP 36821, Irapuato, Guanajuato, Mexico
| | - José A Pedroza-García
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 510-3, 62250, Cuernavaca, Morelos, Mexico
| | - Alfredo Cruz-Ramirez
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, CP 36821, Irapuato, Guanajuato, Mexico
| | - Luis G Brieba
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, Km. 9.6 Libramiento Norte Carretera, Irapuato-León, CP 36821, Irapuato, Guanajuato, Mexico.
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19
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Teng FY, Jiang ZZ, Guo M, Tan XZ, Chen F, Xi XG, Xu Y. G-quadruplex DNA: a novel target for drug design. Cell Mol Life Sci 2021; 78:6557-6583. [PMID: 34459951 PMCID: PMC11072987 DOI: 10.1007/s00018-021-03921-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/13/2021] [Accepted: 08/12/2021] [Indexed: 02/08/2023]
Abstract
G-quadruplex (G4) DNA is a type of quadruple helix structure formed by a continuous guanine-rich DNA sequence. Emerging evidence in recent years authenticated that G4 DNA structures exist both in cell-free and cellular systems, and function in different diseases, especially in various cancers, aging, neurological diseases, and have been considered novel promising targets for drug design. In this review, we summarize the detection method and the structure of G4, highlighting some non-canonical G4 DNA structures, such as G4 with a bulge, a vacancy, or a hairpin. Subsequently, the functions of G4 DNA in physiological processes are discussed, especially their regulation of DNA replication, transcription of disease-related genes (c-MYC, BCL-2, KRAS, c-KIT et al.), telomere maintenance, and epigenetic regulation. Typical G4 ligands that target promoters and telomeres for drug design are also reviewed, including ellipticine derivatives, quinoxaline analogs, telomestatin analogs, berberine derivatives, and CX-5461, which is currently in advanced phase I/II clinical trials for patients with hematologic cancer and BRCA1/2-deficient tumors. Furthermore, since the long-term stable existence of G4 DNA structures could result in genomic instability, we summarized the G4 unfolding mechanisms emerged recently by multiple G4-specific DNA helicases, such as Pif1, RecQ family helicases, FANCJ, and DHX36. This review aims to present a general overview of the field of G-quadruplex DNA that has progressed in recent years and provides potential strategies for drug design and disease treatment.
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Affiliation(s)
- Fang-Yuan Teng
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Zong-Zhe Jiang
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Man Guo
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Xiao-Zhen Tan
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Feng Chen
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Xu-Guang Xi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China.
- LBPA, Ecole Normale Supérieure Paris-Saclay, CNRS, Université Paris Saclay, 61, Avenue du Président Wilson, 94235, Cachan, France.
| | - Yong Xu
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
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20
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Boldinova EO, Yudkina AV, Shilkin ES, Gagarinskaya DI, Baranovskiy AG, Tahirov TH, Zharkov DO, Makarova AV. Translesion activity of PrimPol on DNA with cisplatin and DNA-protein cross-links. Sci Rep 2021; 11:17588. [PMID: 34475447 PMCID: PMC8413282 DOI: 10.1038/s41598-021-96692-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 07/26/2021] [Indexed: 12/24/2022] Open
Abstract
Human PrimPol belongs to the archaeo-eukaryotic primase superfamily of primases and is involved in de novo DNA synthesis downstream of blocking DNA lesions and non-B DNA structures. PrimPol possesses both DNA/RNA primase and DNA polymerase activities, and also bypasses a number of DNA lesions in vitro. In this work, we have analyzed translesion synthesis activity of PrimPol in vitro on DNA with an 1,2-intrastrand cisplatin cross-link (1,2-GG CisPt CL) or a model DNA–protein cross-link (DpCL). PrimPol was capable of the 1,2-GG CisPt CL bypass in the presence of Mn2+ ions and preferentially incorporated two complementary dCMPs opposite the lesion. Nucleotide incorporation was stimulated by PolDIP2, and yeast Pol ζ efficiently extended from the nucleotides inserted opposite the 1,2-GG CisPt CL in vitro. DpCLs significantly blocked the DNA polymerase activity and strand displacement synthesis of PrimPol. However, PrimPol was able to reach the DpCL site in single strand template DNA in the presence of both Mg2+ and Mn2+ ions despite the presence of the bulky protein obstacle.
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Affiliation(s)
- Elizaveta O Boldinova
- Institute of Molecular Genetics, National Research Center «Kurchatov Institute», Kurchatov sq. 2, Moscow, Russia, 123182
| | - Anna V Yudkina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 8 Lavrentiev Avenue, Novosibirsk, Russia, 630090
| | - Evgeniy S Shilkin
- Institute of Molecular Genetics, National Research Center «Kurchatov Institute», Kurchatov sq. 2, Moscow, Russia, 123182
| | - Diana I Gagarinskaya
- Institute of Molecular Genetics, National Research Center «Kurchatov Institute», Kurchatov sq. 2, Moscow, Russia, 123182
| | - Andrey G Baranovskiy
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Tahir H Tahirov
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Dmitry O Zharkov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 8 Lavrentiev Avenue, Novosibirsk, Russia, 630090.,Novosibirsk State University, 2 Pirogova St., Novosibirsk, Russia, 630090
| | - Alena V Makarova
- Institute of Molecular Genetics, National Research Center «Kurchatov Institute», Kurchatov sq. 2, Moscow, Russia, 123182.
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21
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Butler TJ, Estep KN, Sommers JA, Maul RW, Moore AZ, Bandinelli S, Cucca F, Tuke MA, Wood AR, Bharti SK, Bogenhagen DF, Yakubovskaya E, Garcia-Diaz M, Guilliam TA, Byrd AK, Raney KD, Doherty AJ, Ferrucci L, Schlessinger D, Ding J, Brosh RM. Mitochondrial genetic variation is enriched in G-quadruplex regions that stall DNA synthesis in vitro. Hum Mol Genet 2021; 29:1292-1309. [PMID: 32191790 DOI: 10.1093/hmg/ddaa043] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/27/2020] [Accepted: 03/18/2020] [Indexed: 01/08/2023] Open
Abstract
As the powerhouses of the eukaryotic cell, mitochondria must maintain their genomes which encode proteins essential for energy production. Mitochondria are characterized by guanine-rich DNA sequences that spontaneously form unusual three-dimensional structures known as G-quadruplexes (G4). G4 structures can be problematic for the essential processes of DNA replication and transcription because they deter normal progression of the enzymatic-driven processes. In this study, we addressed the hypothesis that mitochondrial G4 is a source of mutagenesis leading to base-pair substitutions. Our computational analysis of 2757 individual genomes from two Italian population cohorts (SardiNIA and InCHIANTI) revealed a statistically significant enrichment of mitochondrial mutations within sequences corresponding to stable G4 DNA structures. Guided by the computational analysis results, we designed biochemical reconstitution experiments and demonstrated that DNA synthesis by two known mitochondrial DNA polymerases (Pol γ, PrimPol) in vitro was strongly blocked by representative stable G4 mitochondrial DNA structures, which could be overcome in a specific manner by the ATP-dependent G4-resolving helicase Pif1. However, error-prone DNA synthesis by PrimPol using the G4 template sequence persisted even in the presence of Pif1. Altogether, our results suggest that genetic variation is enriched in G-quadruplex regions that impede mitochondrial DNA replication.
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Affiliation(s)
- Thomas J Butler
- Translational Gerontology Branch, National Institute on Aging, Baltimore, MD 21224, USA
| | - Katrina N Estep
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Joshua A Sommers
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Robert W Maul
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Ann Zenobia Moore
- Translational Gerontology Branch, National Institute on Aging, Baltimore, MD 21224, USA
| | | | - Francesco Cucca
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, Monserrato 09042, Italy
| | - Marcus A Tuke
- Genetics of Complex Traits, University of Exeter Medical School, Exeter EX1 2LU, UK
| | - Andrew R Wood
- Genetics of Complex Traits, University of Exeter Medical School, Exeter EX1 2LU, UK
| | - Sanjay Kumar Bharti
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Daniel F Bogenhagen
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794-8651, USA
| | - Elena Yakubovskaya
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794-8651, USA
| | - Miguel Garcia-Diaz
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794-8651, USA
| | - Thomas A Guilliam
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton BN1 9RQ, UK
| | - Alicia K Byrd
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Kevin D Raney
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Aidan J Doherty
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton BN1 9RQ, UK
| | - Luigi Ferrucci
- Translational Gerontology Branch, National Institute on Aging, Baltimore, MD 21224, USA
| | - David Schlessinger
- Laboratory of Genetics and Genomics, National Institute on Aging, Baltimore, MD 21224, USA
| | - Jun Ding
- Translational Gerontology Branch, National Institute on Aging, Baltimore, MD 21224, USA
| | - Robert M Brosh
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
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22
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Guilliam TA. Mechanisms for Maintaining Eukaryotic Replisome Progression in the Presence of DNA Damage. Front Mol Biosci 2021; 8:712971. [PMID: 34295925 PMCID: PMC8290200 DOI: 10.3389/fmolb.2021.712971] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/25/2021] [Indexed: 12/04/2022] Open
Abstract
The eukaryotic replisome coordinates template unwinding and nascent-strand synthesis to drive DNA replication fork progression and complete efficient genome duplication. During its advancement along the parental template, each replisome may encounter an array of obstacles including damaged and structured DNA that impede its progression and threaten genome stability. A number of mechanisms exist to permit replisomes to overcome such obstacles, maintain their progression, and prevent fork collapse. A combination of recent advances in structural, biochemical, and single-molecule approaches have illuminated the architecture of the replisome during unperturbed replication, rationalised the impact of impediments to fork progression, and enhanced our understanding of DNA damage tolerance mechanisms and their regulation. This review focusses on these studies to provide an updated overview of the mechanisms that support replisomes to maintain their progression on an imperfect template.
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Affiliation(s)
- Thomas A. Guilliam
- Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
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23
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Bainbridge LJ, Teague R, Doherty AJ. Repriming DNA synthesis: an intrinsic restart pathway that maintains efficient genome replication. Nucleic Acids Res 2021; 49:4831-4847. [PMID: 33744934 PMCID: PMC8136793 DOI: 10.1093/nar/gkab176] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/01/2021] [Accepted: 03/05/2021] [Indexed: 12/25/2022] Open
Abstract
To bypass a diverse range of fork stalling impediments encountered during genome replication, cells possess a variety of DNA damage tolerance (DDT) mechanisms including translesion synthesis, template switching, and fork reversal. These pathways function to bypass obstacles and allow efficient DNA synthesis to be maintained. In addition, lagging strand obstacles can also be circumvented by downstream priming during Okazaki fragment generation, leaving gaps to be filled post-replication. Whether repriming occurs on the leading strand has been intensely debated over the past half-century. Early studies indicated that both DNA strands were synthesised discontinuously. Although later studies suggested that leading strand synthesis was continuous, leading to the preferred semi-discontinuous replication model. However, more recently it has been established that replicative primases can perform leading strand repriming in prokaryotes. An analogous fork restart mechanism has also been identified in most eukaryotes, which possess a specialist primase called PrimPol that conducts repriming downstream of stalling lesions and structures. PrimPol also plays a more general role in maintaining efficient fork progression. Here, we review and discuss the historical evidence and recent discoveries that substantiate repriming as an intrinsic replication restart pathway for maintaining efficient genome duplication across all domains of life.
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Affiliation(s)
- Lewis J Bainbridge
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK
| | - Rebecca Teague
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK
| | - Aidan J Doherty
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK
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24
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Rechkoblit O, Johnson RE, Gupta YK, Prakash L, Prakash S, Aggarwal AK. Structural basis of DNA synthesis opposite 8-oxoguanine by human PrimPol primase-polymerase. Nat Commun 2021; 12:4020. [PMID: 34188055 PMCID: PMC8241999 DOI: 10.1038/s41467-021-24317-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 06/14/2021] [Indexed: 11/30/2022] Open
Abstract
PrimPol is a human DNA polymerase-primase that localizes to mitochondria and nucleus and bypasses the major oxidative lesion 7,8-dihydro-8-oxoguanine (oxoG) via translesion synthesis, in mostly error-free manner. We present structures of PrimPol insertion complexes with a DNA template-primer and correct dCTP or erroneous dATP opposite the lesion, as well as extension complexes with C or A as a 3′−terminal primer base. We show that during the insertion of C and extension from it, the active site is unperturbed, reflecting the readiness of PrimPol to accommodate oxoG(anti). The misinsertion of A opposite oxoG(syn) also does not alter the active site, and is likely less favorable due to lower thermodynamic stability of the oxoG(syn)•A base-pair. During the extension step, oxoG(syn) induces an opening of its base-pair with A or misalignment of the 3′-A primer terminus. Together, the structures show how PrimPol accurately synthesizes DNA opposite oxidatively damaged DNA in human cells. The human DNA primase and DNA polymerase PrimPol replicates through the major oxidative DNA damage lesion 7,8-dihydro-8-oxoguanine (oxoG) via translesion synthesis in a mostly error-free manner thus suppressing oxoG-induced mutagenesis in mitochondria and the nucleus. Here, the authors present crystal structures of PrimPol in complex with an oxoG lesion in different contexts that provide mechanistic insights into how PrimPol performs predominantly accurate synthesis on oxidative-damaged DNAs in human cells.
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Affiliation(s)
- Olga Rechkoblit
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Robert E Johnson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Yogesh K Gupta
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,Greehey Children's Cancer Research Institute & Department of Biochemistry and Structural Biology, University of Texas Health at San Antonio, San Antonio, TX, USA
| | - Louise Prakash
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Satya Prakash
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Aneel K Aggarwal
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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25
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Kulik AA, Maruszczak KK, Thomas DC, Nabi-Aldridge NLA, Carr M, Bingham RJ, Cooper CDO. Crystal structure and molecular dynamics of human POLDIP2, a multifaceted adaptor protein in metabolism and genome stability. Protein Sci 2021; 30:1196-1209. [PMID: 33884680 PMCID: PMC8138528 DOI: 10.1002/pro.4085] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 01/02/2023]
Abstract
Polymerase δ‐interacting protein 2 (POLDIP2, PDIP38) is a multifaceted, “moonlighting” protein, involved in binding protein partners from many different cellular processes, including mitochondrial metabolism and DNA replication and repair. How POLDIP2 interacts with many different proteins is unknown. Towards this goal, we present the crystal structure of POLDIP2 to 2.8 Å, which exhibited a compact two‐domain β‐strand‐rich globular structure, confirmed by circular dichroism and small angle X‐ray scattering approaches. POLDIP2 comprised canonical DUF525 and YccV domains, but with a conserved domain linker packed tightly, resulting in an “extended” YccV module. A central channel was observed, which we hypothesize could influence structural changes potentially mediated by redox conditions, following observation of a modified cysteine residue in the channel. Unstructured regions were rebuilt by ab initio modelling to generate a model of full‐length POLDIP2. Molecular dynamics simulations revealed a highly dynamic N‐terminal region tethered to the YccV‐domain by an extended linker, potentially facilitating interactions with distal binding partners. Models of POLDIP2 complexed with two of its partners, PrimPol and PCNA, indicated that dynamic flexibility of the POLDIP2 N‐terminus and loop regions likely mediate protein interactions. PDB Code(s): 6Z9C;
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Affiliation(s)
- Anastasija A Kulik
- Department of Biological and Geographical Sciences, School of Applied Sciences, University of Huddersfield, Huddersfield, UK
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26
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Kasho K, Stojkovič G, Velázquez-Ruiz C, Martínez-Jiménez MI, Doimo M, Laurent T, Berner A, Pérez-Rivera AE, Jenninger L, Blanco L, Wanrooij S. A unique arginine cluster in PolDIP2 enhances nucleotide binding and DNA synthesis by PrimPol. Nucleic Acids Res 2021; 49:2179-2191. [PMID: 33533925 PMCID: PMC7913696 DOI: 10.1093/nar/gkab049] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Accepted: 01/19/2021] [Indexed: 01/22/2023] Open
Abstract
Replication forks often stall at damaged DNA. To overcome these obstructions and complete the DNA duplication in a timely fashion, replication can be restarted downstream of the DNA lesion. In mammalian cells, this repriming of replication can be achieved through the activities of primase and polymerase PrimPol. PrimPol is stimulated in DNA synthesis through interaction with PolDIP2, however the exact mechanism of this PolDIP2-dependent stimulation is still unclear. Here, we show that PrimPol uses a flexible loop to interact with the C-terminal ApaG-like domain of PolDIP2, and that this contact is essential for PrimPol's enhanced processivity. PolDIP2 increases primer-template and dNTP binding affinities of PrimPol, which concomitantly enhances its nucleotide incorporation efficiency. This stimulation is dependent on a unique arginine cluster in PolDIP2. Since the polymerase activity of PrimPol alone is very limited, this mechanism, where the affinity for dNTPs gets increased by PolDIP2 binding, might be critical for the in vivo function of PrimPol in tolerating DNA lesions at physiological nucleotide concentrations.
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Affiliation(s)
- Kazutoshi Kasho
- Department of Medical Biochemistry and Biophysics, Umeå University, 90187 Umeå, Sweden
| | - Gorazd Stojkovič
- Department of Medical Biochemistry and Biophysics, Umeå University, 90187 Umeå, Sweden
| | | | | | - Mara Doimo
- Department of Medical Biochemistry and Biophysics, Umeå University, 90187 Umeå, Sweden
| | - Timothée Laurent
- Department of Medical Biochemistry and Biophysics, Umeå University, 90187 Umeå, Sweden
| | - Andreas Berner
- Department of Medical Biochemistry and Biophysics, Umeå University, 90187 Umeå, Sweden
| | | | - Louise Jenninger
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Luis Blanco
- Centro de Biologia Molecular Severo Ochoa, E-28049 Madrid, Spain
| | - Sjoerd Wanrooij
- Department of Medical Biochemistry and Biophysics, Umeå University, 90187 Umeå, Sweden
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27
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Quinet A, Tirman S, Cybulla E, Meroni A, Vindigni A. To skip or not to skip: choosing repriming to tolerate DNA damage. Mol Cell 2021; 81:649-658. [PMID: 33515486 PMCID: PMC7935405 DOI: 10.1016/j.molcel.2021.01.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/21/2020] [Accepted: 01/06/2021] [Indexed: 12/14/2022]
Abstract
Accurate DNA replication is constantly threatened by DNA lesions arising from endogenous and exogenous sources. Specialized DNA replication stress response pathways ensure replication fork progression in the presence of DNA lesions with minimal delay in fork elongation. These pathways broadly include translesion DNA synthesis, template switching, and replication fork repriming. Here, we discuss recent advances toward our understanding of the mechanisms that regulate the fine-tuned balance between these different replication stress response pathways. We also discuss the molecular pathways required to fill single-stranded DNA gaps that accumulate throughout the genome after repriming and the biological consequences of using repriming instead of other DNA damage tolerance pathways on genome integrity and cell fitness.
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Affiliation(s)
- Annabel Quinet
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Stephanie Tirman
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA; Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Emily Cybulla
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA; Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Alice Meroni
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA.
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28
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Krupina K, Goginashvili A, Cleveland DW. Causes and consequences of micronuclei. Curr Opin Cell Biol 2021; 70:91-99. [PMID: 33610905 DOI: 10.1016/j.ceb.2021.01.004] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 01/14/2021] [Indexed: 12/14/2022]
Abstract
Micronuclei are small membrane-bounded compartments with a DNA content encapsulated by a nuclear envelope and spatially separated from the primary nucleus. Micronuclei have long been linked to chromosome instability, genome rearrangements, and mutagenesis. They are frequently found in cancers, during senescence, and after genotoxic stress. Compromised integrity of the micronuclear envelope delays or disrupts DNA replication, inhibits DNA repair, and exposes micronuclear DNA directly to cytoplasm. Micronuclei play a central role in tumorigenesis, with micronuclear DNA being a source of complex genome rearrangements (including chromothripsis) and promoting a cyclic GMP-AMP synthase (cGAS)-mediated cellular immune response that may contribute to cancer metastasis. Here, we discuss recent findings on how micronuclei are generated, what the consequences are, and what cellular mechanisms can be applied to protect against micronucleation.
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Affiliation(s)
- Ksenia Krupina
- Ludwig Institute for Cancer Research, University of California at San Diego, La Jolla, CA, 92093, USA; Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, 92093, USA
| | - Alexander Goginashvili
- Ludwig Institute for Cancer Research, University of California at San Diego, La Jolla, CA, 92093, USA; Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, 92093, USA
| | - Don W Cleveland
- Ludwig Institute for Cancer Research, University of California at San Diego, La Jolla, CA, 92093, USA; Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, 92093, USA.
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29
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Tirman S, Cybulla E, Quinet A, Meroni A, Vindigni A. PRIMPOL ready, set, reprime! Crit Rev Biochem Mol Biol 2021; 56:17-30. [PMID: 33179522 PMCID: PMC7906090 DOI: 10.1080/10409238.2020.1841089] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/15/2020] [Accepted: 10/20/2020] [Indexed: 12/14/2022]
Abstract
DNA replication forks are constantly challenged by DNA lesions induced by endogenous and exogenous sources. DNA damage tolerance mechanisms ensure that DNA replication continues with minimal effects on replication fork elongation either by using specialized DNA polymerases, which have the ability to replicate through the damaged template, or by skipping the damaged DNA, leaving it to be repaired after replication. These mechanisms are evolutionarily conserved in bacteria, yeast, and higher eukaryotes, and are paramount to ensure timely and faithful duplication of the genome. The Primase and DNA-directed Polymerase (PRIMPOL) is a recently discovered enzyme that possesses both primase and polymerase activities. PRIMPOL is emerging as a key player in DNA damage tolerance, particularly in vertebrate and human cells. Here, we review our current understanding of the function of PRIMPOL in DNA damage tolerance by focusing on the structural aspects that define its dual enzymatic activity, as well as on the mechanisms that control its chromatin recruitment and expression levels. We also focus on the latest findings on the mitochondrial and nuclear functions of PRIMPOL and on the impact of loss of these functions on genome stability and cell survival. Defining the function of PRIMPOL in DNA damage tolerance is becoming increasingly important in the context of human disease. In particular, we discuss recent evidence pointing at the PRIMPOL pathway as a novel molecular target to improve cancer cell response to DNA-damaging chemotherapy and as a predictive parameter to stratify patients in personalized cancer therapy.
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Affiliation(s)
- Stephanie Tirman
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis MO, 63110, USA
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Emily Cybulla
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis MO, 63110, USA
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Annabel Quinet
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis MO, 63110, USA
| | - Alice Meroni
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis MO, 63110, USA
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis MO, 63110, USA
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30
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Yan Y, Xu Z, Huang J, Guo G, Gao M, Kim W, Zeng X, Kloeber JA, Zhu Q, Zhao F, Luo K, Lou Z. The deubiquitinase USP36 Regulates DNA replication stress and confers therapeutic resistance through PrimPol stabilization. Nucleic Acids Res 2021; 48:12711-12726. [PMID: 33237263 PMCID: PMC7736794 DOI: 10.1093/nar/gkaa1090] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 10/21/2020] [Accepted: 10/29/2020] [Indexed: 02/07/2023] Open
Abstract
PrimPol has been recently identified as a DNA damage tolerant polymerase that plays an important role in replication stress response. However, the regulatory mechanisms of PrimPol are not well defined. In this study, we identify that the deubiquitinase USP36 interferes with degradation of PrimPol to regulate the replication stress response. Mechanistically, USP36 is deubiquitinated following DNA replication stress, which in turn facilitates its upregulation and interaction with PrimPol. USP36 deubiquitinates K29-linked polyubiquitination of PrimPol and increases its protein stability. Depletion of USP36 results in replication stress-related defects and elevates cell sensitivity to DNA-damage agents, such as cisplatin and olaparib. Moreover, USP36 expression positively correlates with the level of PrimPol protein and poor prognosis in patient samples. These findings indicate that the regulation of PrimPol K29-linked ubiquitination by USP36 plays a critical role in DNA replication stress and chemotherapy response.
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Affiliation(s)
- Yuanliang Yan
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha 410008, Hunan, China.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Zhijie Xu
- Department of Pathology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, Hunan, China
| | - Jinzhou Huang
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Guijie Guo
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Ming Gao
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Wootae Kim
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Xiangyu Zeng
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Jake A Kloeber
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA.,Mayo Clinic Medical Scientist Training Program, Mayo Clinic, Rochester, MN 55905, USA.,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA
| | - Qian Zhu
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Fei Zhao
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Kuntian Luo
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Zhenkun Lou
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
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31
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Piberger AL, Bowry A, Kelly RDW, Walker AK, González-Acosta D, Bailey LJ, Doherty AJ, Méndez J, Morris JR, Bryant HE, Petermann E. PrimPol-dependent single-stranded gap formation mediates homologous recombination at bulky DNA adducts. Nat Commun 2020; 11:5863. [PMID: 33203852 PMCID: PMC7673990 DOI: 10.1038/s41467-020-19570-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 10/15/2020] [Indexed: 11/09/2022] Open
Abstract
Stalled replication forks can be restarted and repaired by RAD51-mediated homologous recombination (HR), but HR can also perform post-replicative repair after bypass of the obstacle. Bulky DNA adducts are important replication-blocking lesions, but it is unknown whether they activate HR at stalled forks or behind ongoing forks. Using mainly BPDE-DNA adducts as model lesions, we show that HR induced by bulky adducts in mammalian cells predominantly occurs at post-replicative gaps formed by the DNA/RNA primase PrimPol. RAD51 recruitment under these conditions does not result from fork stalling, but rather occurs at gaps formed by PrimPol re-priming and resection by MRE11 and EXO1. In contrast, RAD51 loading at double-strand breaks does not require PrimPol. At bulky adducts, PrimPol promotes sister chromatid exchange and genetic recombination. Our data support that HR at bulky adducts in mammalian cells involves post-replicative gap repair and define a role for PrimPol in HR-mediated DNA damage tolerance.
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Affiliation(s)
- Ann Liza Piberger
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
| | - Akhil Bowry
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Richard D W Kelly
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Alexandra K Walker
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | | | - Laura J Bailey
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK
| | - Aidan J Doherty
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK
| | - Juan Méndez
- Molecular Oncology Program, Spanish National Cancer Research Centre, Madrid, Spain
| | - Joanna R Morris
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Helen E Bryant
- Department of Oncology & Metabolism, The Medical School, University of Sheffield, Sheffield, S10 2RX, UK
| | - Eva Petermann
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
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Boguszewska K, Szewczuk M, Kaźmierczak-Barańska J, Karwowski BT. The Similarities between Human Mitochondria and Bacteria in the Context of Structure, Genome, and Base Excision Repair System. Molecules 2020; 25:E2857. [PMID: 32575813 PMCID: PMC7356350 DOI: 10.3390/molecules25122857] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/17/2020] [Accepted: 06/19/2020] [Indexed: 02/06/2023] Open
Abstract
Mitochondria emerged from bacterial ancestors during endosymbiosis and are crucial for cellular processes such as energy production and homeostasis, stress responses, cell survival, and more. They are the site of aerobic respiration and adenosine triphosphate (ATP) production in eukaryotes. However, oxidative phosphorylation (OXPHOS) is also the source of reactive oxygen species (ROS), which are both important and dangerous for the cell. Human mitochondria contain mitochondrial DNA (mtDNA), and its integrity may be endangered by the action of ROS. Fortunately, human mitochondria have repair mechanisms that allow protecting mtDNA and repairing lesions that may contribute to the occurrence of mutations. Mutagenesis of the mitochondrial genome may manifest in the form of pathological states such as mitochondrial, neurodegenerative, and/or cardiovascular diseases, premature aging, and cancer. The review describes the mitochondrial structure, genome, and the main mitochondrial repair mechanism (base excision repair (BER)) of oxidative lesions in the context of common features between human mitochondria and bacteria. The authors present a holistic view of the similarities of mitochondria and bacteria to show that bacteria may be an interesting experimental model for studying mitochondrial diseases, especially those where the mechanism of DNA repair is impaired.
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Affiliation(s)
| | | | | | - Bolesław T. Karwowski
- DNA Damage Laboratory of Food Science Department, Faculty of Pharmacy, Medical University of Lodz, ul. Muszynskiego 1, 90-151 Lodz, Poland; (K.B.); (M.S.); (J.K.-B.)
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Liptay M, Barbosa JS, Rottenberg S. Replication Fork Remodeling and Therapy Escape in DNA Damage Response-Deficient Cancers. Front Oncol 2020; 10:670. [PMID: 32432041 PMCID: PMC7214843 DOI: 10.3389/fonc.2020.00670] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/09/2020] [Indexed: 12/27/2022] Open
Abstract
Most cancers have lost a critical DNA damage response (DDR) pathway during tumor evolution. These alterations provide a useful explanation for the initial sensitivity of tumors to DNA-targeting chemotherapy. A striking example is dysfunctional homology-directed repair (HDR), e.g., due to inactivating mutations in BRCA1 and BRCA2 genes. Extensive efforts are being made to develop novel targeted therapies exploiting such an HDR defect. Inhibitors of poly(ADP-ribose) polymerase (PARP) are an instructive example of this approach. Despite the success of PARP inhibitors, the presence of primary or acquired therapy resistance remains a major challenge in clinical oncology. To move the field of precision medicine forward, we need to understand the precise mechanisms causing therapy resistance. Using preclinical models, various mechanisms underlying chemotherapy resistance have been identified. Restoration of HDR seems to be a prevalent mechanism but this does not explain resistance in all cases. Interestingly, some factors involved in DNA damage response (DDR) have independent functions in replication fork (RF) biology and their loss causes RF instability and therapy sensitivity. However, in BRCA-deficient tumors, loss of these factors leads to restored stability of RFs and acquired drug resistance. In this review we discuss the recent advances in the field of RF biology and its potential implications for chemotherapy response in DDR-defective cancers. Additionally, we review the role of DNA damage tolerance (DDT) pathways in maintenance of genome integrity and their alterations in cancer. Furthermore, we refer to novel tools that, combined with a better understanding of drug resistance mechanisms, may constitute a great advance in personalized diagnosis and therapeutic strategies for patients with HDR-deficient tumors.
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Affiliation(s)
- Martin Liptay
- Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Joana S. Barbosa
- Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Sven Rottenberg
- Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Bern Center for Precision Medicine, University of Bern, Bern, Switzerland
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Sharma N, Pasala MS, Prakash A. Mitochondrial DNA: Epigenetics and environment. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2019; 60:668-682. [PMID: 31335990 PMCID: PMC6941438 DOI: 10.1002/em.22319] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/08/2019] [Accepted: 07/11/2019] [Indexed: 05/22/2023]
Abstract
Maintenance of the mitochondrial genome is essential for proper cellular function. For this purpose, mitochondrial DNA (mtDNA) needs to be faithfully replicated, transcribed, translated, and repaired in the face of constant onslaught from endogenous and environmental agents. Although only 13 polypeptides are encoded within mtDNA, the mitochondrial proteome comprises over 1500 proteins that are encoded by nuclear genes and translocated to the mitochondria for the purpose of maintaining mitochondrial function. Regulation of mtDNA and mitochondrial proteins by epigenetic changes and post-translational modifications facilitate crosstalk between the nucleus and the mitochondria and ultimately lead to the maintenance of cellular health and homeostasis. DNA methyl transferases have been identified in the mitochondria implicating that methylation occurs within this organelle; however, the extent to which mtDNA is methylated has been debated for many years. Mechanisms of demethylation within this organelle have also been postulated, but the exact mechanisms and their outcomes is still an active area of research. Mitochondrial dysfunction in the form of altered gene expression and ATP production, resulting from epigenetic changes, can lead to various conditions including aging-related neurodegenerative disorders, altered metabolism, changes in circadian rhythm, and cancer. Here, we provide an overview of the epigenetic regulation of mtDNA via methylation, long and short noncoding RNAs, and post-translational modifications of nucleoid proteins (as mitochondria lack histones). We also highlight the influence of xenobiotics such as airborne environmental pollutants, contamination from heavy metals, and therapeutic drugs on mtDNA methylation. Environ. Mol. Mutagen., 60:668-682, 2019. © 2019 Wiley Periodicals, Inc.
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