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Jahjah T, Singh JK, Gottifredi V, Quinet A. Tolerating DNA damage by repriming: Gap filling in the spotlight. DNA Repair (Amst) 2024; 142:103758. [PMID: 39236419 DOI: 10.1016/j.dnarep.2024.103758] [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: 05/17/2024] [Revised: 08/14/2024] [Accepted: 08/25/2024] [Indexed: 09/07/2024]
Abstract
Timely and accurate DNA replication is critical for safeguarding genome integrity and ensuring cell viability. Yet, this process is challenged by DNA damage blocking the progression of the replication machinery. To counteract replication fork stalling, evolutionary conserved DNA damage tolerance (DDT) mechanisms promote DNA damage bypass and fork movement. One of these mechanisms involves "skipping" DNA damage through repriming downstream of the lesion, leaving single-stranded DNA (ssDNA) gaps behind the advancing forks (also known as post-replicative gaps). In vertebrates, repriming in damaged leading templates is proposed to be mainly promoted by the primase and polymerase PRIMPOL. In this review, we discuss recent advances towards our understanding of the physiological and pathological conditions leading to repriming activation in human models, revealing a regulatory network of PRIMPOL activity. Upon repriming by PRIMPOL, post-replicative gaps formed can be filled-in by the DDT mechanisms translesion synthesis and template switching. We discuss novel findings on how these mechanisms are regulated and coordinated in time to promote gap filling. Finally, we discuss how defective gap filling and aberrant gap expansion by nucleases underlie the cytotoxicity associated with post-replicative gap accumulation. Our increasing knowledge of this repriming mechanism - from gap formation to gap filling - is revealing that targeting the last step of this pathway is a promising approach to exploit post-replicative gaps in anti-cancer therapeutic strategies.
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Affiliation(s)
- Tiya Jahjah
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses F-92265, France; Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses F-92265, France
| | - Jenny K Singh
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses F-92265, France; Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses F-92265, France
| | - Vanesa Gottifredi
- Fundación Instituto Leloir, IIBBA, CONICET, Buenos Aires 1405, Argentina
| | - Annabel Quinet
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses F-92265, France; Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses F-92265, France.
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Başar Kılıç Ş, Taheri S, Mehmetbeyoğlu Duman E, Öksüm Solak E, Yılmaz Şükranlı Z, Rassoulzadegan M, Borlu M. Psoriatic skin transcript phenotype: androgen/estrogen and cortisone/cortisol imbalance with increasing DNA damage response. Mol Biol Rep 2024; 51:933. [PMID: 39180588 DOI: 10.1007/s11033-024-09782-1] [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: 03/30/2024] [Accepted: 07/04/2024] [Indexed: 08/26/2024]
Abstract
BACKGROUND Patients prone to psoriasis suffer after a breakdown of the epidermal barrier and develop poorly healing lesions with abnormal proliferation of keratinocytes. Strong inflammatory reactions with genotoxicity (short telomeres) suggest impaired immune defenses with DNA damage repair response (DDR) in patients with psoriasis. Recent evidence indicates the existence of crosstalk mechanisms linking the DDR machinery and hormonal signaling pathways that cooperate to influence both progressions of many diseases and responses to treatment. The aim of this study was to clarify whether steroid biosynthesis and genomic stability markers are altered in parallel during the formation of psoriatic skin. Understanding the interaction of the steroid pathway and DNA damage response is crucial to addressing underlying fundamental issues and managing resulting epidermal barrier disruption in psoriasis. METHODS Skin (Lesional, non-lesional) and blood samples from twenty psoriasis patients and fifteen healthy volunteers were collected. Real-Time-PCR study was performed to assess levels of known transcripts such as: estrogen (ESR1, ESR2), androgen (AR), glucocorticoid/mineralocorticoid receptors (NR3C1, NR3C2), HSD11B1/HSD11B2, and DNA damage sensors (SMC1A, TREX1, TREX2, SSBP3, RAD1, RAD18, EXO1, POLH, HUS1). RESULTS We found that ESR1, ESR2, HSD11B1, NR3C1, NR3C2, POLH, and SMC1A transcripts were significantly decreased and AR, TREX1, RAD1, and SSBP3 transcripts were increased dramatically in the lesional skin compared to skin samples of controls. CONCLUSION We found that the regulation of the steroidogenic pathway was disrupted in the lesional tissue of psoriasis patients and that a sufficient glucocorticoid and mineralocorticoid response did not form and the estrogen/androgen balance was altered in favour of androgens. We suggest that an increased androgen response in the presence of DDR increases the risk of developing psoriasis. Although this situation may be the cause or the consequence of a disruption of the epidermal barrier, our data suggest developing new therapeutic strategies.
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Affiliation(s)
- Şeyma Başar Kılıç
- Dermatology and Venereology Department, Faculty of Medicine, Aksaray University, Aksaray, Turkey
| | - Serpil Taheri
- Medical Biology Department, Faculty of Medicine, Erciyes University, Kayseri, Turkey
- Betul Ziya Eren Genome and Stem Cell Center, Erciyes University, Kayseri, Turkey
| | - Ecmel Mehmetbeyoğlu Duman
- Betul Ziya Eren Genome and Stem Cell Center, Erciyes University, Kayseri, Turkey
- Department of Cancer and Genetics, Cardiff University, Cardiff, CF14 4XN, UK
| | - Eda Öksüm Solak
- Dermatology and Venereology Department, Faculty of Medicine, Erciyes University, Kayseri, Turkey
| | | | - Minoo Rassoulzadegan
- Betul Ziya Eren Genome and Stem Cell Center, Erciyes University, Kayseri, Turkey
| | - Murat Borlu
- Dermatology and Venereology Department, Faculty of Medicine, Erciyes University, Kayseri, Turkey.
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Liljegren MM, Gama JA, Johnsen PJ, Harms K. The recombination initiation functions DprA and RecFOR suppress microindel mutations in Acinetobacter baylyi ADP1. Mol Microbiol 2024; 122:1-10. [PMID: 38760330 DOI: 10.1111/mmi.15277] [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: 11/22/2023] [Revised: 04/24/2024] [Accepted: 04/26/2024] [Indexed: 05/19/2024]
Abstract
Short-Patch Double Illegitimate Recombination (SPDIR) has been recently identified as a rare mutation mechanism. During SPDIR, ectopic DNA single-strands anneal with genomic DNA at microhomologies and get integrated during DNA replication, presumably acting as primers for Okazaki fragments. The resulting microindel mutations are highly variable in size and sequence. In the soil bacterium Acinetobacter baylyi, SPDIR is tightly controlled by genome maintenance functions including RecA. It is thought that RecA scavenges DNA single-strands and renders them unable to anneal. To further elucidate the role of RecA in this process, we investigate the roles of the upstream functions DprA, RecFOR, and RecBCD, all of which load DNA single-strands with RecA. Here we show that all three functions suppress SPDIR mutations in the wildtype to levels below the detection limit. While SPDIR mutations are slightly elevated in the absence of DprA, they are strongly increased in the absence of both DprA and RecA. This SPDIR-avoiding function of DprA is not related to its role in natural transformation. These results suggest a function for DprA in combination with RecA to avoid potentially harmful microindel mutations, and offer an explanation for the ubiquity of dprA in the genomes of naturally non-transformable bacteria.
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Affiliation(s)
- Mikkel M Liljegren
- Microbial Pharmacology and Population Biology Research Group, Department of Pharmacy, UiT The Arctic University of Norway, Tromsø, Norway
| | - João A Gama
- Microbial Pharmacology and Population Biology Research Group, Department of Pharmacy, UiT The Arctic University of Norway, Tromsø, Norway
- Department of Microbiology, Ramón y Cajal University Hospital, Ramón y Cajal Institute for Health Research (IRYCIS), Madrid, Spain
| | - Pål J Johnsen
- Microbial Pharmacology and Population Biology Research Group, Department of Pharmacy, UiT The Arctic University of Norway, Tromsø, Norway
| | - Klaus Harms
- Microbial Pharmacology and Population Biology Research Group, Department of Pharmacy, UiT The Arctic University of Norway, Tromsø, Norway
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Ribeiro D, Latancia M, de Souza I, Ariwoola AB, Mendes D, Rocha CRR, Lengert A, Menck C. Temozolomide resistance mechanisms: unveiling the role of translesion DNA polymerase kappa in glioblastoma spheroids in vitro. Biosci Rep 2024; 44:BSR20230667. [PMID: 38717250 PMCID: PMC11139666 DOI: 10.1042/bsr20230667] [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: 12/11/2023] [Revised: 04/22/2024] [Accepted: 05/07/2024] [Indexed: 05/30/2024] Open
Abstract
Temozolomide (TMZ) is the leading therapeutic agent for combating Glioblastoma Multiforme (GBM). Nonetheless, the persistence of chemotherapy-resistant GBM cells remains an ongoing challenge, attributed to various factors, including the translesion synthesis (TLS) mechanism. TLS enables tumor cells to endure genomic damage by utilizing specialized DNA polymerases to bypass DNA lesions. Specifically, TLS polymerase Kappa (Polκ) has been implicated in facilitating DNA damage tolerance against TMZ-induced damage, contributing to a worse prognosis in GBM patients. To better understand the roles of Polκ in TMZ resistance, we conducted a comprehensive assessment of the cytotoxic, antiproliferative, antimetastatic, and genotoxic effects of TMZ on GBM (U251MG) wild-type (WTE) and TLS Polκ knockout (KO) cells, cultivated as three-dimensional (3D) tumor spheroids in vitro. Initial results revealed that TMZ: (i) induces reductions in GBM spheroid diameter (10-200 µM); (ii) demonstrates significant cytotoxicity (25-200 μM); (iii) exerts antiproliferative effects (≤25 μM) and promotes cell cycle arrest (G2/M phase) in Polκ KO spheroids when compared with WTE counterparts. Furthermore, Polκ KO spheroids exhibit elevated levels of cell death (Caspase 3/7) and display greater genotoxicity (53BP1) than WTE following TMZ exposure. Concerning antimetastatic effects, TMZ impedes invadopodia (3D invasion) more effectively in Polκ KO than in WTE spheroids. Collectively, the results suggest that TLS Polκ plays a vital role in the survival, cell death, genotoxicity, and metastatic potential of GBM spheroids in vitro when subjected to TMZ treatment. While the precise mechanisms underpinning this resistance remain elusive, TLS Polκ emerges as a potential therapeutic target for GBM patients.
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Affiliation(s)
- Diego Luis Ribeiro
- Departament of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil
| | - Marcela Teatin Latancia
- Departament of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil
| | - Izadora de Souza
- Department of Clinical and Experimental Oncology, Federal University of São Paulo, São Paulo, São Paulo, Brazil
| | - Abu-Bakr Adetayo Ariwoola
- Departament of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil
- Department of Clinical and Experimental Oncology, Federal University of São Paulo, São Paulo, São Paulo, Brazil
| | - Davi Mendes
- Departament of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil
| | | | - André Van Helvoort Lengert
- Department of Biophysics, Paulista School of Medicine, Federal University of São Paulo, São Paulo, São Paulo, Brazil
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Mórocz M, Qorri E, Pekker E, Tick G, Haracska L. Exploring RAD18-dependent replication of damaged DNA and discontinuities: A collection of advanced tools. J Biotechnol 2024; 380:1-19. [PMID: 38072328 DOI: 10.1016/j.jbiotec.2023.12.001] [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: 10/11/2023] [Revised: 12/01/2023] [Accepted: 12/03/2023] [Indexed: 12/21/2023]
Abstract
DNA damage tolerance (DDT) pathways mitigate the effects of DNA damage during replication by rescuing the replication fork stalled at a DNA lesion or other barriers and also repair discontinuities left in the newly replicated DNA. From yeast to mammalian cells, RAD18-regulated translesion synthesis (TLS) and template switching (TS) represent the dominant pathways of DDT. Monoubiquitylation of the polymerase sliding clamp PCNA by HRAD6A-B/RAD18, an E2/E3 protein pair, enables the recruitment of specialized TLS polymerases that can insert nucleotides opposite damaged template bases. Alternatively, the subsequent polyubiquitylation of monoubiquitin-PCNA by Ubc13-Mms2 (E2) and HLTF or SHPRH (E3) can lead to the switching of the synthesis from the damaged template to the undamaged newly synthesized sister strand to facilitate synthesis past the lesion. When immediate TLS or TS cannot occur, gaps may remain in the newly synthesized strand, partly due to the repriming activity of the PRIMPOL primase, which can be filled during the later phases of the cell cycle. The first part of this review will summarize the current knowledge about RAD18-dependent DDT pathways, while the second part will offer a molecular toolkit for the identification and characterization of the cellular functions of a DDT protein. In particular, we will focus on advanced techniques that can reveal single-stranded and double-stranded DNA gaps and their repair at the single-cell level as well as monitor the progression of single replication forks, such as the specific versions of the DNA fiber and comet assays. This collection of methods may serve as a powerful molecular toolkit to monitor the metabolism of gaps, detect the contribution of relevant pathways and molecular players, as well as characterize the effectiveness of potential inhibitors.
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Affiliation(s)
- Mónika Mórocz
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary.
| | - Erda Qorri
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary; Faculty of Science and Informatics, Doctoral School of Biology, University of Szeged, Szeged H-6720, Hungary.
| | - Emese Pekker
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary; Doctoral School of Interdisciplinary Medicine, University of Szeged, Korányi fasor 10, 6720 Szeged, Hungary.
| | - Gabriella Tick
- Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary.
| | - Lajos Haracska
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary; National Laboratory for Drug Research and Development, Magyar tudósok krt. 2. H-1117 Budapest, Hungary.
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Menck CFM, Galhardo RS, Quinet A. The accurate bypass of pyrimidine dimers by DNA polymerase eta contributes to ultraviolet-induced mutagenesis. Mutat Res 2024; 828:111840. [PMID: 37984186 DOI: 10.1016/j.mrfmmm.2023.111840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 10/23/2023] [Accepted: 11/02/2023] [Indexed: 11/22/2023]
Abstract
Human xeroderma pigmentosum variant (XP-V) patients are mutated in the POLH gene, responsible for encoding the translesion synthesis (TLS) DNA polymerase eta (Pol eta). These patients suffer from a high frequency of skin tumors. Despite several decades of research, studies on Pol eta still offer an intriguing paradox: How does this error-prone polymerase suppress mutations? This review examines recent evidence suggesting that cyclobutane pyrimidine dimers (CPDs) are instructional for Pol eta. Consequently, it can accurately replicate these lesions, and the mutagenic effects induced by UV radiation stem from the deamination of C-containing CPDs. In this model, the deamination of C (forming a U) within CPDs leads to the correct insertion of an A opposite to the deaminated C (or U)-containing dimers. This intricate process results in C>T transitions, which represent the most prevalent mutations detected in skin cancers. Finally, the delayed replication in XP-V cells amplifies the process of C-deamination in CPDs and increases the burden of C>T mutations prevalent in XP-V tumors through the activity of backup TLS polymerases.
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Affiliation(s)
- C F M Menck
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil.
| | - R S Galhardo
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - A Quinet
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, F-92265 Fontenay-aux-Roses, France; Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, F-92265 Fontenay-aux-Roses, France
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Martins DJ, Singh JK, Jahjah T, Vessoni AT, Leandro GDS, Silva MM, Biard DSF, Quinet A, Menck CFM. Polymerase iota plays a key role during translesion synthesis of UV-induced lesions in the absence of polymerase eta. Photochem Photobiol 2024; 100:4-18. [PMID: 37926965 DOI: 10.1111/php.13879] [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: 06/22/2023] [Revised: 09/29/2023] [Accepted: 10/18/2023] [Indexed: 11/07/2023]
Abstract
Xeroderma pigmentosum (XP) variant cells are deficient in the translesion synthesis (TLS) DNA polymerase Polη (eta). This protein contributes to DNA damage tolerance, bypassing unrepaired UV photoproducts and allowing S-phase progression with minimal delay. In the absence of Polη, backup polymerases perform TLS of UV lesions. However, which polymerase plays this role in human cells remains an open question. Here, we investigated the potential role of Polι (iota) in bypassing ultraviolet (UV) induced photoproducts in the absence of Polη, using NER-deficient (XP-C) cells knocked down for Polι and/or Polη genes. Our results indicate that cells lacking either Polι or Polη have increased sensitivity to UVC radiation. The lack of both TLS polymerases led to increased cell death and defects in proliferation and migration. Loss of both polymerases induces a significant replication fork arrest and G1/S-phase blockage, compared to the lack of Polη alone. In conclusion, we propose that Polι acts as a bona fide backup for Polη in the TLS of UV-photoproducts.
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Affiliation(s)
- Davi Jardim Martins
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, Sao Paulo, Brazil
| | - Jenny Kaur Singh
- Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses, France
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses, France
| | - Tiya Jahjah
- Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses, France
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses, France
| | - Alexandre Teixeira Vessoni
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, Sao Paulo, Brazil
- Sanofi R&D, Vitry-sur-Seine, France
| | - Giovana da Silva Leandro
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, Sao Paulo, Brazil
| | - Matheus Molina Silva
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, Sao Paulo, Brazil
| | - Denis Serge François Biard
- Université Paris-Saclay, Institut de Biologie François Jacob, Service d'étude des prions et maladies atypiques, iRCM/IBJF, Fontenay-aux-Roses, France
| | - Annabel Quinet
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, Sao Paulo, Brazil
- Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses, France
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, Fontenay-aux-Roses, France
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Venkadakrishnan J, Lahane G, Dhar A, Xiao W, Bhat KM, Pandita TK, Bhat A. Implications of Translesion DNA Synthesis Polymerases on Genomic Stability and Human Health. Mol Cell Biol 2023; 43:401-425. [PMID: 37439479 PMCID: PMC10448981 DOI: 10.1080/10985549.2023.2224199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 05/03/2023] [Accepted: 06/01/2023] [Indexed: 07/14/2023] Open
Abstract
Replication fork arrest-induced DNA double strand breaks (DSBs) caused by lesions are effectively suppressed in cells due to the presence of a specialized mechanism, commonly referred to as DNA damage tolerance (DDT). In eukaryotic cells, DDT is facilitated through translesion DNA synthesis (TLS) carried out by a set of DNA polymerases known as TLS polymerases. Another parallel mechanism, referred to as homology-directed DDT, is error-free and involves either template switching or fork reversal. The significance of the DDT pathway is well established. Several diseases have been attributed to defects in the TLS pathway, caused either by mutations in the TLS polymerase genes or dysregulation. In the event of a replication fork encountering a DNA lesion, cells switch from high-fidelity replicative polymerases to low-fidelity TLS polymerases, which are associated with genomic instability linked with several human diseases including, cancer. The role of TLS polymerases in chemoresistance has been recognized in recent years. In addition to their roles in the DDT pathway, understanding noncanonical functions of TLS polymerases is also a key to unraveling their importance in maintaining genomic stability. Here we summarize the current understanding of TLS pathway in DDT and its implication for human health.
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Affiliation(s)
| | - Ganesh Lahane
- Department of Pharmacy, Birla Institute of Technology and Sciences Pilani, Hyderabad Campus, Hyderabad, India
| | - Arti Dhar
- Department of Pharmacy, Birla Institute of Technology and Sciences Pilani, Hyderabad Campus, Hyderabad, India
| | - Wei Xiao
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
| | - Krishna Moorthi Bhat
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, USA
| | - Tej K. Pandita
- Center for Genomics and Precision Medicine, Texas A&M College of Medicine, Houston, Texas, USA
| | - Audesh Bhat
- Center for Molecular Biology, Central University of Jammu, UT Jammu and Kashmir, India
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Anand J, Chiou L, Sciandra C, Zhang X, Hong J, Wu D, Zhou P, Vaziri C. Roles of trans-lesion synthesis (TLS) DNA polymerases in tumorigenesis and cancer therapy. NAR Cancer 2023; 5:zcad005. [PMID: 36755961 PMCID: PMC9900426 DOI: 10.1093/narcan/zcad005] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/10/2022] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
DNA damage tolerance and mutagenesis are hallmarks and enabling characteristics of neoplastic cells that drive tumorigenesis and allow cancer cells to resist therapy. The 'Y-family' trans-lesion synthesis (TLS) DNA polymerases enable cells to replicate damaged genomes, thereby conferring DNA damage tolerance. Moreover, Y-family DNA polymerases are inherently error-prone and cause mutations. Therefore, TLS DNA polymerases are potential mediators of important tumorigenic phenotypes. The skin cancer-propensity syndrome xeroderma pigmentosum-variant (XPV) results from defects in the Y-family DNA Polymerase Pol eta (Polη) and compensatory deployment of alternative inappropriate DNA polymerases. However, the extent to which dysregulated TLS contributes to the underlying etiology of other human cancers is unclear. Here we consider the broad impact of TLS polymerases on tumorigenesis and cancer therapy. We survey the ways in which TLS DNA polymerases are pathologically altered in cancer. We summarize evidence that TLS polymerases shape cancer genomes, and review studies implicating dysregulated TLS as a driver of carcinogenesis. Because many cancer treatment regimens comprise DNA-damaging agents, pharmacological inhibition of TLS is an attractive strategy for sensitizing tumors to genotoxic therapies. Therefore, we discuss the pharmacological tractability of the TLS pathway and summarize recent progress on development of TLS inhibitors for therapeutic purposes.
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Affiliation(s)
- Jay Anand
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, 614 Brinkhous-Bullitt Building, Chapel Hill, NC 27599, USA
| | - Lilly Chiou
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, 614 Brinkhous-Bullitt Building, Chapel Hill, NC 27599, USA
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Carly Sciandra
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Xingyuan Zhang
- Department of Biostatistics, University of North Carolina at Chapel Hill, 135 Dauer Drive, 3101 McGavran-Greenberg Hall, Chapel Hill, NC 27599, USA
| | - Jiyong Hong
- Department of Chemistry, Duke University, Durham, NC 27708, USA
| | - Di Wu
- Department of Biostatistics, University of North Carolina at Chapel Hill, 135 Dauer Drive, 3101 McGavran-Greenberg Hall, Chapel Hill, NC 27599, USA
| | - Pei Zhou
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Cyrus Vaziri
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, 614 Brinkhous-Bullitt Building, Chapel Hill, NC 27599, USA
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Mitotic DNA synthesis in response to replication stress requires the sequential action of DNA polymerases zeta and delta in human cells. Nat Commun 2023; 14:706. [PMID: 36759509 PMCID: PMC9911744 DOI: 10.1038/s41467-023-35992-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 01/11/2023] [Indexed: 02/11/2023] Open
Abstract
Oncogene activation creates DNA replication stress (RS) in cancer cells, which can generate under-replicated DNA regions (UDRs) that persist until cells enter mitosis. UDRs also have the potential to generate DNA bridges in anaphase cells or micronuclei in the daughter cells, which could promote genomic instability. To suppress such damaging changes to the genome, human cells have developed a strategy to conduct 'unscheduled' DNA synthesis in mitosis (termed MiDAS) that serves to rescue under-replicated loci. Previous studies have shown that MiDAS proceeds via a POLD3-dependent pathway that shows some features of break-induced replication. Here, we define how human cells utilize both DNA gap filling (REV1 and Pol ζ) and replicative (Pol δ) DNA polymerases to complete genome duplication following a perturbed S-phase. We present evidence for the existence of a polymerase-switch during MiDAS that is required for new DNA synthesis at UDRs. Moreover, we reveal that, upon oncogene activation, cancer cell survival is significantly compromised when REV1 is depleted, suggesting that REV1 inhibition might be a feasible approach for the treatment of some human cancers.
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Cheong A, Nagel ZD. Human Variation in DNA Repair, Immune Function, and Cancer Risk. Front Immunol 2022; 13:899574. [PMID: 35935942 PMCID: PMC9354717 DOI: 10.3389/fimmu.2022.899574] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
DNA damage constantly threatens genome integrity, and DNA repair deficiency is associated with increased cancer risk. An intuitive and widely accepted explanation for this relationship is that unrepaired DNA damage leads to carcinogenesis due to the accumulation of mutations in somatic cells. But DNA repair also plays key roles in the function of immune cells, and immunodeficiency is an important risk factor for many cancers. Thus, it is possible that emerging links between inter-individual variation in DNA repair capacity and cancer risk are driven, at least in part, by variation in immune function, but this idea is underexplored. In this review we present an overview of the current understanding of the links between cancer risk and both inter-individual variation in DNA repair capacity and inter-individual variation in immune function. We discuss factors that play a role in both types of variability, including age, lifestyle, and environmental exposures. In conclusion, we propose a research paradigm that incorporates functional studies of both genome integrity and the immune system to predict cancer risk and lay the groundwork for personalized prevention.
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12
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Feltes BC, Menck CFM. Current state of knowledge of human DNA polymerase eta protein structure and disease-causing mutations. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2022; 790:108436. [PMID: 35952573 DOI: 10.1016/j.mrrev.2022.108436] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 06/29/2022] [Accepted: 07/31/2022] [Indexed: 01/01/2023]
Abstract
POLη, encoded by the POLH gene, is a crucial protein for replicating damaged DNA and the most studied specialized translesion synthesis polymerases. Mutations in POLη are associated with cancer and the human syndrome xeroderma pigmentosum variant, which is characterized by extreme photosensitivity and an increased likelihood of developing skin cancers. The myriad of structural information about POLη is vast, covering dozens of different mutants, numerous crucial residues, domains, and posttranslational modifications that are essential for protein function within cells. Since POLη is key vital enzyme for cell survival, and mutations in this protein are related to aggressive diseases, understanding its structure is crucial for biomedical sciences, primarily due to its similarities with other Y-family polymerases and its potential as a targeted therapy-drug for tumors. This work provides an up-to-date review on structural aspects of the human POLη: from basic knowledge about critical residues and protein domains to its mutant variants, posttranslational modifications, and our current understanding of therapeutic molecules that target POLη. Thus, this review provides lessons about POLη's structure and gathers critical discussions and hypotheses that may contribute to understanding this protein's vital roles within the cells.
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Affiliation(s)
- Bruno César Feltes
- Department of Theoretical Informatics, Institute of Informatics, Department of Theoretical Informatics, Federal University of Rio Grande do Sul, Porto Alegre, RS Brazil; Department of Genetics, Institute of Bioscience, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil; Department of Biophysics, Institute of Bioscience, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
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13
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Ler AAL, Carty MP. DNA Damage Tolerance Pathways in Human Cells: A Potential Therapeutic Target. Front Oncol 2022; 11:822500. [PMID: 35198436 PMCID: PMC8859465 DOI: 10.3389/fonc.2021.822500] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 12/30/2021] [Indexed: 12/26/2022] Open
Abstract
DNA lesions arising from both exogenous and endogenous sources occur frequently in DNA. During DNA replication, the presence of unrepaired DNA damage in the template can arrest replication fork progression, leading to fork collapse, double-strand break formation, and to genome instability. To facilitate completion of replication and prevent the generation of strand breaks, DNA damage tolerance (DDT) pathways play a key role in allowing replication to proceed in the presence of lesions in the template. The two main DDT pathways are translesion synthesis (TLS), which involves the recruitment of specialized TLS polymerases to the site of replication arrest to bypass lesions, and homology-directed damage tolerance, which includes the template switching and fork reversal pathways. With some exceptions, lesion bypass by TLS polymerases is a source of mutagenesis, potentially contributing to the development of cancer. The capacity of TLS polymerases to bypass replication-blocking lesions induced by anti-cancer drugs such as cisplatin can also contribute to tumor chemoresistance. On the other hand, during homology-directed DDT the nascent sister strand is transiently utilised as a template for replication, allowing for error-free lesion bypass. Given the role of DNA damage tolerance pathways in replication, mutagenesis and chemoresistance, a more complete understanding of these pathways can provide avenues for therapeutic exploitation. A number of small molecule inhibitors of TLS polymerase activity have been identified that show synergy with conventional chemotherapeutic agents in killing cancer cells. In this review, we will summarize the major DDT pathways, explore the relationship between damage tolerance and carcinogenesis, and discuss the potential of targeting TLS polymerases as a therapeutic approach.
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Affiliation(s)
- Ashlynn Ai Li Ler
- Biochemistry, School of Biological and Chemical Sciences, The National University of Ireland (NUI) Galway, Galway, Ireland
| | - Michael P. Carty
- Biochemistry, School of Biological and Chemical Sciences, The National University of Ireland (NUI) Galway, Galway, Ireland
- DNA Damage Response Laboratory, Centre for Chromosome Biology, NUI Galway, Galway, Ireland
- *Correspondence: Michael P. Carty,
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14
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Quintero-Ruiz N, Corradi C, Moreno NC, de Souza TA, Pereira Castro L, Rocha CRR, Menck CFM. Mutagenicity Profile Induced by UVB Light in Human Xeroderma Pigmentosum Group C Cells †. Photochem Photobiol 2021; 98:713-731. [PMID: 34516658 DOI: 10.1111/php.13516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 09/07/2021] [Indexed: 11/29/2022]
Abstract
Nucleotide excision repair (NER) is one of the main pathways for genome protection against structural DNA damage caused by sunlight, which in turn is extensively related to skin cancer development. The mutation spectra induced by UVB were investigated by whole-exome sequencing of randomly selected clones of NER-proficient and XP-C-deficient human skin fibroblasts. As a model, a cell line unable to recognize and remove lesions (XP-C) was used and compared to the complemented isogenic control (COMP). As expected, a significant increase of mutagenesis was observed in irradiated XP-C cells, mainly C>T transitions, but also CC>TT and C>A base substitutions. Remarkably, the C>T mutations occur mainly at the second base of dipyrimidine sites in pyrimidine-rich sequence contexts, with 5'TC sequence the most mutated. Although T>N mutations were also significantly increased, they were not directly related to pyrimidine dimers. Moreover, the large-scale study of a single UVB irradiation on XP-C cells allowed recovering the typical mutation spectrum found in human skin cancer tumors. Eventually, the data may be used for comparison with the mutational profiles of skin tumors obtained from XP-C patients and may help to understand the mutational process in nonaffected individuals.
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Affiliation(s)
- Nathalia Quintero-Ruiz
- Laboratorio de reparo de DNA, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Camila Corradi
- Laboratorio de reparo de DNA, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Natália Cestari Moreno
- Laboratorio de reparo de DNA, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.,Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Tiago Antonio de Souza
- Laboratorio de reparo de DNA, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.,Tau GC Bioinformatics, São Paulo, Brazil
| | - Ligia Pereira Castro
- Laboratorio de reparo de DNA, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Clarissa Ribeiro Reily Rocha
- Laboratorio de reparo de DNA, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.,Drug resistance and mutagenesis Laboratory, Departmento de Oncologia Clínica e Experimental, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Carlos Frederico Martins Menck
- Laboratorio de reparo de DNA, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
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15
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Ma L, Li X, Zhao X, Sun H, Kong F, Li Y, Sui Y, Xu F. Oxaliplatin promotes siMAD2L2‑induced apoptosis in colon cancer cells. Mol Med Rep 2021; 24:629. [PMID: 34278473 PMCID: PMC8281267 DOI: 10.3892/mmr.2021.12268] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 05/26/2021] [Indexed: 02/07/2023] Open
Abstract
The clinical efficacy of colorectal tumor treatment is restricted due to platinum agent resistance. Translesion DNA synthesis (TLS) has been shown to contribute to this resistance; however, the exact molecular mechanism remains unknown. The present study aimed to investigate the possible function of the core of the TLS polymerase mitotic arrest deficient 2 like 2 (MAD2L2) in drug sensitivity, in order to provide a treatment rationale for platinum‑based chemotherapy in colon cancer. In the present study, MAD2L2 was knocked down using MAD2L2‑specific small interfering (si)RNA. HCT116 and SW620 cells were treated with oxaliplatin and MG132; oxaliplatin is a platinum compound that induces DNA damage and MG132 is a potent proteasome inhibitor. Cell viability was determined using an MTT assay. Cell apoptosis was examined via flow cytometry and TUNEL assay. The activity of proteasome 26S subunit, non‑ATPase 13 (PSMD13) was detected using ELISA, while the expression levels of apoptotic‑related proteins were detected via western blotting. The results demonstrated that cells treated with oxaliplatin or MG132 alone had decreased viability, but a synergistic effect was not observed after co‑treatment. In addition, the knockdown of MAD2L2 caused by siMAD2L2 or oxaliplatin treatment increased the expression levels of the pro‑apoptotic proteins Bax and Bak and decreased the expression levels of the anti‑apoptotic protein Bcl‑2, compared with the negative control group. Moreover, MG132 alleviated the decrease in MAD2L2 expression, while reducing siMAD2L2‑induced cell apoptosis. These results indicate that oxaliplatin promotes siMAD2L2‑induced apoptosis in colon cancer cells. This process was associated with the Bcl‑2 and ubiquitin‑proteasome pathway. Overall, the present study provides a theoretical basis for improving the clinical efficacy of colon cancer by combining chemotherapy and gene therapy.
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Affiliation(s)
- Lu Ma
- Department of Medical Genetics and Cell Biology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
- Key Laboratory of Reproduction and Genetics, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Xin Li
- Department of Medical Genetics and Cell Biology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
- Key Laboratory of Reproduction and Genetics, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Xiaopeng Zhao
- Department of Medical Genetics and Cell Biology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
- Key Laboratory of Reproduction and Genetics, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Haotong Sun
- Department of Medical Genetics and Cell Biology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
- Key Laboratory of Reproduction and Genetics, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Feifei Kong
- Department of Oncology, Qufu People's Hospital, Qufu, Shandong 273100, P.R. China
| | - Yuanjie Li
- Department of Medical Genetics and Cell Biology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
- Key Laboratory of Reproduction and Genetics, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Yu Sui
- Department of Medical Genetics and Cell Biology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
- Key Laboratory of Reproduction and Genetics, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Fang Xu
- Department of Medical Genetics and Cell Biology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
- Key Laboratory of Reproduction and Genetics, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
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16
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Wong RP, Petriukov K, Ulrich HD. Daughter-strand gaps in DNA replication - substrates of lesion processing and initiators of distress signalling. DNA Repair (Amst) 2021; 105:103163. [PMID: 34186497 DOI: 10.1016/j.dnarep.2021.103163] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/18/2021] [Accepted: 06/19/2021] [Indexed: 10/21/2022]
Abstract
Dealing with DNA lesions during genome replication is particularly challenging because damaged replication templates interfere with the progression of the replicative DNA polymerases and thereby endanger the stability of the replisome. A variety of mechanisms for the recovery of replication forks exist, but both bacteria and eukaryotic cells also have the option of continuing replication downstream of the lesion, leaving behind a daughter-strand gap in the newly synthesized DNA. In this review, we address the significance of these single-stranded DNA structures as sites of DNA damage sensing and processing at a distance from ongoing genome replication. We describe the factors controlling the emergence of daughter-strand gaps from stalled replication intermediates, the benefits and risks of their expansion and repair via translesion synthesis or recombination-mediated template switching, and the mechanisms by which they activate local as well as global replication stress signals. Our growing understanding of daughter-strand gaps not only identifies them as targets of fundamental genome maintenance mechanisms, but also suggests that proper control over their activities has important practical implications for treatment strategies and resistance mechanisms in cancer therapy.
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Affiliation(s)
- Ronald P Wong
- Institute of Molecular Biology (IMB) gGmbH, Ackermannweg 4, D - 55128 Mainz, Germany
| | - Kirill Petriukov
- Institute of Molecular Biology (IMB) gGmbH, Ackermannweg 4, D - 55128 Mainz, Germany
| | - Helle D Ulrich
- Institute of Molecular Biology (IMB) gGmbH, Ackermannweg 4, D - 55128 Mainz, Germany.
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17
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Bhutani P, Murray MT, Sommer CW, Wilson KA, Wetmore SD. Structural Rationalization for the Nonmutagenic and Mutagenic Bypass of the Tobacco-Derived O4-4-(3-Pyridyl)-4-oxobut-1-yl-thymine Lesion by Human Polymerase η: A Multiscale Computational Study. Chem Res Toxicol 2021; 34:1619-1629. [PMID: 33856186 DOI: 10.1021/acs.chemrestox.1c00063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Tobacco-derived pyridyloxobutyl (POB) DNA adducts are unique due to the large size and flexibility of the alkyl chain connecting the pyridyl ring to the nucleobase. Recent experimental work suggests that the O4-4-(3-pyridyl)-4-oxobut-1-yl-T (O4-POB-T) lesion can undergo both nonmutagenic (dATP) and mutagenic (dGTP) insertion by the translesion synthesis (TLS) polymerase (pol) η in human cells. Interestingly, the mutagenic rate for O4-POB-T replication is reduced compared to that for the smaller O4-methylthymine (O4-Me-T) lesion, and O4-POB-T yields a different mutagenic profile than the O2-POB-T variant (dTTP insertion). The present work uses a combination of density functional theory calculations and molecular dynamics simulations to probe the impact of the size and flexibility of O4-POB-T on pol η replication outcomes. Due to changes in the Watson-Crick binding face upon damage of canonical T, O4-POB-T does not form favorable hydrogen-bonding interactions with A. Nevertheless, dATP is positioned for insertion in the pol η active site by a water chain to the template strand, which suggests a pol η replication pathway similar to that for abasic sites. Although a favorable O4-POB-T:G mispair forms in the pol η active site and DNA duplexes, the inherent dynamical nature of O4-POB-T periodically disrupts interstrand hydrogen bonding that would otherwise facilitate dGTP insertion and stabilize damaged DNA duplexes. In addition to explaining the origin of the experimentally reported pol η outcomes associated with O4-POB-T replication, comparison to structural data for the O4-Me-T and O2-POB-T adducts highlights an emerging common pathway for the nonmutagenic replication of thymine alkylated lesions by pol η, yet underscores the broader impacts of bulky moiety size, flexibility, and position on the associated mutagenic outcomes.
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Affiliation(s)
- Priya Bhutani
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, Canada T1K 3M4
| | - Makay T Murray
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, Canada T1K 3M4
| | - Craig W Sommer
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, Canada T1K 3M4
| | - Katie A Wilson
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, Canada T1K 3M4
| | - Stacey D Wetmore
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, Canada T1K 3M4
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18
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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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19
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Suzuki T, Sassa A, Grúz P, Gupta RC, Johnson F, Adachi N, Nohmi T. Error-prone bypass patch by a low-fidelity variant of DNA polymerase zeta in human cells. DNA Repair (Amst) 2021; 100:103052. [PMID: 33607474 DOI: 10.1016/j.dnarep.2021.103052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/16/2021] [Accepted: 01/20/2021] [Indexed: 11/15/2022]
Abstract
DNA polymerase ζ (Pol ζ) is a specialized Pol that is involved in translesion DNA synthesis (TLS), in particular, in the extension of primer DNA after bypassing DNA lesions. Previously, we established human cells that express a variant form of Pol ζ with an amino acid change of leucine 2618 to methionine (L2618M) in the catalytic subunit REV3L (DNA Repair, 45, 34-43, 2016). This amino acid change made the cells more sensitive to the mutagenicity of benzo[a]pyrene diol epoxide (BPDE). In this study, we embedded BPDE-N2-guanine at a defined position in the supF gene on the shuttle plasmid and introduced it to REV3 L2618M cells or the wild-type (WT) cells to examine how far Pol ζ L2618M extends the primer DNA after bypassing the lesion. The adduct induced primarily G to T and G to C at the adducted site in both cell lines, but generated additional sequence changes such as base substitutions, deletions and additions in the extension patch much more often in REV3 L2618M cells than in the WT cells. Mutations in the extension patch in REV3 L2618M cells occurred most often within 10 bps from the adducted site. Then, the number of mutations gradually decreased and no mutations were observed between 30 and 40 bps from the lesion. We concluded that human Pol ζ L2618M and perhaps WT Pol ζ extend the primer DNA up to approximately 30 bps from the lesion in vivo. The possibility of involvement of Pol ζ L2618M in the insertion step of TLS is discussed.
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Affiliation(s)
- Tetsuya Suzuki
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan.
| | - Akira Sassa
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan
| | - Petr Grúz
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan
| | - Ramesh C Gupta
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, 11794-3400, NY, United States
| | - Francis Johnson
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, 11794-3400, NY, United States
| | - Noritaka Adachi
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, Kanagawa, 236-0027, Japan
| | - Takehiko Nohmi
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501, Japan
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20
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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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21
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Saha P, Mandal T, Talukdar AD, Kumar D, Kumar S, Tripathi PP, Wang QE, Srivastava AK. DNA polymerase eta: A potential pharmacological target for cancer therapy. J Cell Physiol 2020; 236:4106-4120. [PMID: 33184862 DOI: 10.1002/jcp.30155] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/21/2020] [Accepted: 11/02/2020] [Indexed: 12/24/2022]
Abstract
In the last two decades, intensive research has been carried out to improve the survival rates of cancer patients. However, the development of chemoresistance that ultimately leads to tumor relapse poses a critical challenge for the successful treatment of cancer patients. Many cancer patients experience tumor relapse and ultimately die because of treatment failure associated with acquired drug resistance. Cancer cells utilize multiple lines of self-defense mechanisms to bypass chemotherapy and radiotherapy. One such mechanism employed by cancer cells is translesion DNA synthesis (TLS), in which specialized TLS polymerases bypass the DNA lesion with the help of monoubiquitinated proliferating cell nuclear antigen. Among all TLS polymerases (Pol η, Pol ι, Pol κ, REV1, Pol ζ, Pol μ, Pol λ, Pol ν, and Pol θ), DNA polymerase eta (Pol η) is well studied and majorly responsible for the bypass of cisplatin and UV-induced DNA damage. TLS polymerases contribute to chemotherapeutic drug-induced mutations as well as therapy resistance. Therefore, targeting these polymerases presents a novel therapeutic strategy to combat chemoresistance. Mounting evidence suggests that inhibition of Pol η may have multiple impacts on cancer therapy such as sensitizing cancer cells to chemotherapeutics, suppressing drug-induced mutagenesis, and inhibiting the development of secondary tumors. Herein, we provide a general introduction of Pol η and its clinical implications in blocking acquired drug resistance. In addition; this review addresses the existing gaps and challenges of Pol η mediated TLS mechanisms in human cells. A better understanding of the Pol η mediated TLS mechanism will not merely establish it as a potential pharmacological target but also open possibilities to identify novel drug targets for future therapy.
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Affiliation(s)
- Priyanka Saha
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, West Bengal, India
| | - Tanima Mandal
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, West Bengal, India
| | - Anupam D Talukdar
- Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India
| | - Deepak Kumar
- Organic & Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata, West Bengal, India
| | - Sanjay Kumar
- Division of Biology, Indian Institute of Science Education and Research (IISER) Tirupati, Andhra Pradesh, India
| | - Prem P Tripathi
- Cell Biology & Physiology Division, CSIR-Indian Institute of Chemical Biology, Kolkata, West Bengal, India
| | - Qi-En Wang
- Department of Radiation Oncology, Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, USA
| | - Amit K Srivastava
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, West Bengal, India
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22
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Poveda A, Méndez MÁ, Armijos-Jaramillo V. Analysis of DNA Polymerases Reveals Specific Genes Expansion in Leishmania and Trypanosoma spp. Front Cell Infect Microbiol 2020; 10:570493. [PMID: 33117729 PMCID: PMC7576959 DOI: 10.3389/fcimb.2020.570493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 09/02/2020] [Indexed: 01/01/2023] Open
Abstract
Leishmaniasis and trypanosomiasis are largely neglected diseases prevailing in tropical and subtropical conditions. These are an arthropod-borne zoonosis that affects humans and some animals and is caused by infection with protozoan of the genera Leishmania and Trypanosoma, respectively. These parasites present high genomic plasticity and are able to adapt themselves to adverse conditions like the attack of host cells or toxicity induced by drug exposure. Different mechanisms allow these adapting responses induced by stress, such as mutation, chromosomal rearrangements, establishment of mosaic ploidies, and gene expansion. Here we describe how a subset of genes encoding for DNA polymerases implied in repairing/translesion (TLS) synthesis are duplicated in some pathogenic species of the Trypanosomatida order and a free-living species from the Bodonida order. These enzymes are both able to repair DNA, but are also error-prone under certain situations. We discuss about the possibility that these enzymes can act as a source of genomic variation promoting adaptation in trypanosomatids.
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Affiliation(s)
- Ana Poveda
- DNA Replication and Genome Instability Unit, Grupo de Investigación en Biodiversidad, Zoonosis y Salud Pública (GIBCIZ), Instituto de Investigación en Salud Pública y Zoonosis-CIZ, Facultad de Ciencias Químicas, Universidad Central del Ecuador, Quito, Ecuador.,Departamento de Bioquímica y Biología Molecular, Universidad de Valencia, Burjassot, Spain
| | - Miguel Ángel Méndez
- Grupo de Química Computacional y Teórica, Universidad San Francisco de Quito, Quito, Ecuador
| | - Vinicio Armijos-Jaramillo
- Grupo de Bio-Quimioinformática, Carrera de Ingeniería en Biotecnología, Facultad de Ingeniería y Ciencias Aplicadas, Universidad de Las Américas, Quito, Ecuador
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23
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Zhang H. Mechanisms of mutagenesis induced by DNA lesions: multiple factors affect mutations in translesion DNA synthesis. Crit Rev Biochem Mol Biol 2020; 55:219-251. [PMID: 32448001 DOI: 10.1080/10409238.2020.1768205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Environmental mutagens lead to mutagenesis. However, the mechanisms are very complicated and not fully understood. Environmental mutagens produce various DNA lesions, including base-damaged or sugar-modified DNA lesions, as well as epigenetically modified DNA. DNA polymerases produce mutation spectra in translesion DNA synthesis (TLS) through misincorporation of incorrect nucleotides, frameshift deletions, blockage of DNA replication, imbalance of leading- and lagging-strand DNA synthesis, and genome instability. Motif or subunit in DNA polymerases further affects the mutations in TLS. Moreover, protein interactions and accessory proteins in DNA replisome also alter mutations in TLS, demonstrated by several representative DNA replisomes. Finally, in cells, multiple DNA polymerases or cellular proteins collaborate in TLS and reduce in vivo mutagenesis. Summaries and perspectives were listed. This review shows mechanisms of mutagenesis induced by DNA lesions and the effects of multiple factors on mutations in TLS in vitro and in vivo.
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Affiliation(s)
- Huidong Zhang
- Key Laboratory of Environment and Female Reproductive Health, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China
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24
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Pathogenesis of Photoaging in Human Dermal Fibroblasts. INTERNATIONAL JOURNAL OF DERMATOLOGY AND VENEREOLOGY 2020. [DOI: 10.1097/jd9.0000000000000068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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25
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McIntyre J. Polymerase iota - an odd sibling among Y family polymerases. DNA Repair (Amst) 2019; 86:102753. [PMID: 31805501 DOI: 10.1016/j.dnarep.2019.102753] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 12/14/2022]
Abstract
It has been two decades since the discovery of the most mutagenic human DNA polymerase, polymerase iota (Polι). Since then, the biochemical activity of this translesion synthesis (TLS) enzyme has been extensively explored, mostly through in vitro experiments, with some insight into its cellular activity. Polι is one of four members of the Y-family of polymerases, which are the best characterized DNA damage-tolerant polymerases involved in TLS. Polι shares some common Y-family features, including low catalytic efficiency and processivity, high infidelity, the ability to bypass some DNA lesions, and a deficiency in 3'→5' exonucleolytic proofreading. However, Polι exhibits numerous properties unique among the Y-family enzymes. Polι has an unusual catalytic pocket structure and prefers Hoogsteen over Watson-Crick pairing, and its replication fidelity strongly depends on the template; further, it prefers Mn2+ ions rather than Mg2+ as catalytic activators. In addition to its polymerase activity, Polι possesses also 5'-deoxyribose phosphate (dRP) lyase activity, and its ability to participate in base excision repair has been shown. As a highly error-prone polymerase, its regulation is crucial and mostly involves posttranslational modifications and protein-protein interactions. The upregulation and downregulation of Polι are correlated with different types of cancer and suggestions regarding the possible function of this polymerase have emerged from studies of various cancer lines. Nonetheless, after twenty years of research, the biological function of Polι certainly remains unresolved.
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Affiliation(s)
- Justyna McIntyre
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, ul. Pawinskiego 5a, 02-106, Warsaw, Poland.
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26
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Quinet A, Tirman S, Jackson J, Šviković S, Lemaçon D, Carvajal-Maldonado D, González-Acosta D, Vessoni AT, Cybulla E, Wood M, Tavis S, Batista LFZ, Méndez J, Sale JE, Vindigni A. PRIMPOL-Mediated Adaptive Response Suppresses Replication Fork Reversal in BRCA-Deficient Cells. Mol Cell 2019; 77:461-474.e9. [PMID: 31676232 PMCID: PMC7007862 DOI: 10.1016/j.molcel.2019.10.008] [Citation(s) in RCA: 151] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 07/29/2019] [Accepted: 10/07/2019] [Indexed: 12/20/2022]
Abstract
Acute treatment with replication-stalling chemotherapeutics causes reversal of replication forks. BRCA proteins protect reversed forks from nucleolytic degradation, and their loss leads to chemosensitivity. Here, we show that fork degradation is no longer detectable in BRCA1-deficient cancer cells exposed to multiple cisplatin doses, mimicking a clinical treatment regimen. This effect depends on increased expression and chromatin loading of PRIMPOL and is regulated by ATR activity. Electron microscopy and single-molecule DNA fiber analyses reveal that PRIMPOL rescues fork degradation by reinitiating DNA synthesis past DNA lesions. PRIMPOL repriming leads to accumulation of ssDNA gaps while suppressing fork reversal. We propose that cells adapt to repeated cisplatin doses by activating PRIMPOL repriming under conditions that would otherwise promote pathological reversed fork degradation. This effect is generalizable to other conditions of impaired fork reversal (e.g., SMARCAL1 loss or PARP inhibition) and suggests a new strategy to modulate cisplatin chemosensitivity by targeting the PRIMPOL pathway. Multiple cisplatin doses suppress reversed fork degradation in BRCA-deficient cells The PRIMPOL adaptive response suppresses fork reversal and leads to ssDNA gaps The ATR kinase regulates the PRIMPOL-mediated adaptive response Impaired fork reversal shifts the balance toward PRIMPOL-mediated repriming
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Affiliation(s)
- Annabel Quinet
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Stephanie Tirman
- Division of Oncology, Department of Medicine, Washington University in St. Louis, 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
| | - Jessica Jackson
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Saša Šviković
- Division of Protein & Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Delphine Lemaçon
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Denisse Carvajal-Maldonado
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | | | - Alexandre T Vessoni
- Division of Hematology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Emily Cybulla
- Division of Oncology, Department of Medicine, Washington University in St. Louis, 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
| | - Matthew Wood
- Division of Oncology, Department of Medicine, Washington University in St. Louis, 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
| | - Steven Tavis
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Luis F Z Batista
- Division of Hematology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Juan Méndez
- Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Julian E Sale
- Division of Protein & Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University in St. Louis, 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.
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