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Donato L, Scimone C, Alibrandi S, Mordà D, Anchesi I, Scalinci SZ, Rinaldi C, D'Angelo R, Sidoti A. Investigating G-quadruplex structures in RPGR gene: Implications for understanding X-linked retinal degeneration. Heliyon 2024; 10:e29828. [PMID: 38699732 PMCID: PMC11063440 DOI: 10.1016/j.heliyon.2024.e29828] [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: 02/19/2024] [Revised: 03/31/2024] [Accepted: 04/16/2024] [Indexed: 05/05/2024] Open
Abstract
Aims This pilot study investigates the potential pathogenic role of G-quadruplex (G4) structures in RPGR-associated retinal degeneration, starting from a case of suspected X-linked form affected family. We hypothesize that the stabilization of these structures might alter DNA replication and transcription, inducing genetic instability and influencing gene expression. Main methods We conducted whole genome amplification experiments and next-generation sequencing to detect the blockade of polymerase activity by G4 structures. Our specific focus was the RPGR gene, which hosts a high concentration of predicted G4-forming motifs and is implicated in most X-linked retinal degeneration cases. To understand the potential interference of G4 structures, we applied computational and 3D molecular modeling to visualize interferences in DNA replication and transcription regulation. Key findings Our data confirmed the obstruction of DNA polymerase enzymes by G4 structures, particularly when stabilized by the compound pyridostatin. This obstruction was evident in the reduced amplification of RPGR gene regions and a shift in the start/end sites of putative G4 motifs. Moreover, the modeling indicated a potential disruption of critical promoter elements and RNA polymerase binding, which could drastically alter gene expression. Significance Our findings suggest that G4 formation in the RPGR gene could lead to genetic instability and affect the expression of RPGR, contributing to retinal dystrophy. Moreover, this study underscores the broader implications of G4 structures in other genetic disorders. Improved understanding of G4 structures could reveal novel therapeutic targets to combat genetic disorders, promoting the advancement of personalized medicine and precision health.
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Affiliation(s)
- Luigi Donato
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, Messina, 98125, Italy
- Department of Biomolecular Strategies, Genetics and Cutting-Edge Therapies, I.E.ME.S.T., Palermo, 90139, Italy
| | - Concetta Scimone
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, Messina, 98125, Italy
- Department of Biomolecular Strategies, Genetics and Cutting-Edge Therapies, I.E.ME.S.T., Palermo, 90139, Italy
| | - Simona Alibrandi
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, Messina, 98125, Italy
- Department of Biomolecular Strategies, Genetics and Cutting-Edge Therapies, I.E.ME.S.T., Palermo, 90139, Italy
| | - Domenico Mordà
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, Messina, 98125, Italy
- Department of Biomolecular Strategies, Genetics and Cutting-Edge Therapies, I.E.ME.S.T., Palermo, 90139, Italy
- Department of Veterinary Sciences, University of Messina, 98122, Messina, Italy
| | - Ivan Anchesi
- IRCCS Centro Neurolesi "Bonino-Pulejo", Via Provinciale Palermo, Contrada Casazza, 98124, Messina, Italy
| | | | - Carmela Rinaldi
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, Messina, 98125, Italy
| | - Rosalia D'Angelo
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, Messina, 98125, Italy
| | - Antonina Sidoti
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, Messina, 98125, Italy
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Papageorgiou AC, Pospisilova M, Cibulka J, Ashraf R, Waudby CA, Kadeřávek P, Maroz V, Kubicek K, Prokop Z, Krejci L, Tripsianes K. Recognition and coacervation of G-quadruplexes by a multifunctional disordered region in RECQ4 helicase. Nat Commun 2023; 14:6751. [PMID: 37875529 PMCID: PMC10598209 DOI: 10.1038/s41467-023-42503-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 10/12/2023] [Indexed: 10/26/2023] Open
Abstract
Biomolecular polyelectrolyte complexes can be formed between oppositely charged intrinsically disordered regions (IDRs) of proteins or between IDRs and nucleic acids. Highly charged IDRs are abundant in the nucleus, yet few have been functionally characterized. Here, we show that a positively charged IDR within the human ATP-dependent DNA helicase Q4 (RECQ4) forms coacervates with G-quadruplexes (G4s). We describe a three-step model of charge-driven coacervation by integrating equilibrium and kinetic binding data in a global numerical model. The oppositely charged IDR and G4 molecules form a complex in the solution that follows a rapid nucleation-growth mechanism leading to a dynamic equilibrium between dilute and condensed phases. We also discover a physical interaction with Replication Protein A (RPA) and demonstrate that the IDR can switch between the two extremes of the structural continuum of complexes. The structural, kinetic, and thermodynamic profile of its interactions revealed a dynamic disordered complex with nucleic acids and a static ordered complex with RPA protein. The two mutually exclusive binding modes suggest a regulatory role for the IDR in RECQ4 function by enabling molecular handoffs. Our study extends the functional repertoire of IDRs and demonstrates a role of polyelectrolyte complexes involved in G4 binding.
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Affiliation(s)
- Anna C Papageorgiou
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Michaela Pospisilova
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jakub Cibulka
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Raghib Ashraf
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Christopher A Waudby
- Institute of Structural and Molecular Biology, University College London, London, WC1E 6BT, UK
- School of Pharmacy, University College London, London, WC1N 1AX, UK
| | - Pavel Kadeřávek
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Volha Maroz
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Karel Kubicek
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Zbynek Prokop
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
- International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic
| | - Lumir Krejci
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic.
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
- International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic.
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Zeng H, Xie H, Ma Q, Zhuang Y, Luo B, Liao M, Nie H, He J, Tang Z, Zhang S. Identification of N-(3-(methyl(3-(orotic amido)propyl)amino)propyl) oleanolamide as a novel topoisomerase I catalytic inhibitor by rational design, molecular dynamics simulation, and biological evaluation. Bioorg Chem 2023; 139:106734. [PMID: 37473480 DOI: 10.1016/j.bioorg.2023.106734] [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: 05/22/2023] [Revised: 07/05/2023] [Accepted: 07/11/2023] [Indexed: 07/22/2023]
Abstract
DNA topoisomerase I (TOP1) catalytic inhibitors are a promising class of antitumor agents. Oleanolic acid derivatives are potential TOP1 catalytic inhibitors. However, their inhibitory activity still needs to be enhanced, and the stability and hotspot residue sites of their interaction with TOP1 remain to be elucidated. Herein, a novel oleanolic acid derivative, OA4 (N-(3-(methyl(3-(orotic amido)propyl)amino)propyl)oleanolamide), was identified by rational design. Subsequently, molecular dynamics simulations were performed to explore the stability and conformational dynamics of the TOP1-OA4 complex. The molecular mechanics/generalized Born surface area method calculated the binding free energy and predicted Arg488, Ile535, and His632 to be hotspot residues. Biological experiments verified that OA4 is a nonintercalative TOP1 catalytic inhibitor. OA4 exhibits better proliferation inhibitory activity against tumor cells than normal cells. Furthermore, OA4 can induce apoptosis and effectively suppress the proliferation and migration of cancer cells. This work provides new insights for the development of novel TOP1 catalytic inhibitors.
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Affiliation(s)
- Huang Zeng
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China
| | - Huasong Xie
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China
| | - Qiaonan Ma
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China
| | - Yuanbei Zhuang
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China
| | - Baoping Luo
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China
| | - Mei Liao
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China
| | - Hua Nie
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China
| | - Junwei He
- Jiangxi University of Chinese Medicine, Nanchang 330004, China
| | - Zhanyong Tang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| | - Shengyuan Zhang
- Institute of Hakka Medicinal Bio-resources, Medical College, Jiaying University, Meizhou 514031, China.
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Panova VV, Dolinnaya NG, Novoselov KA, Savitskaya VY, Chernykh IS, Kubareva EA, Alexeevski AV, Zvereva MI. Conserved G-Quadruplex-Forming Sequences in Mammalian TERT Promoters and Their Effect on Mutation Frequency. Life (Basel) 2023; 13:1478. [PMID: 37511853 PMCID: PMC10381784 DOI: 10.3390/life13071478] [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: 06/24/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
Somatic mutations in the promoter region of the human telomerase reverse transcriptase (hTERT) gene have been identified in many types of cancer. The hTERT promoter is known to be enriched with sequences that enable the formation of G-quadruplex (G4) structures, whose presence is associated with elevated mutagenicity and genome instability. Here, we used a bioinformatics tool (QGRS mapper) to search for G4-forming sequences (G4 motifs) in the 1000 bp TERT promoter regions of 141 mammalian species belonging to 20 orders, 5 of which, including primates and predators, contain more than 10 species. Groups of conserved G4 motifs and single-nucleotide variants within these groups were discovered using a block alignment approach (based on the Nucleotide PanGenome explorer). It has been shown that: (i) G4 motifs are predominantly located in the region proximal to the transcription start site (up to 400 bp) and are over-represented on the non-coding strand of the TERT promoters, (ii) 11 to 22% of the G4 motifs found are evolutionarily conserved across the related organisms, and (iii) a statistically significant higher frequency of nucleotide substitutions in the conserved G4 motifs compared to the surrounding regions was confirmed only for the order Primates. These data support the assumption that G4s can interfere with the DNA repair process and affect the evolutionary adaptation of organisms and species.
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Affiliation(s)
- Vera V Panova
- Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119234, Russia
| | - Nina G Dolinnaya
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119991, Russia
| | - Kirill A Novoselov
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119991, Russia
| | - Viktoriia Yu Savitskaya
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119991, Russia
| | - Ivan S Chernykh
- Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119234, Russia
| | - Elena A Kubareva
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia
| | - Andrei V Alexeevski
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia
- Department of Mathematics, Scientific Research Institute for System Studies, Russian Academy of Sciences, Nakhimovskii Prospekt 36-1, Moscow 117218, Russia
| | - Maria I Zvereva
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119991, Russia
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Papp C, Mukundan VT, Jenjaroenpun P, Winnerdy FR, Ow GS, Phan AT, Kuznetsov VA. Stable bulged G-quadruplexes in the human genome: identification, experimental validation and functionalization. Nucleic Acids Res 2023; 51:4148-4177. [PMID: 37094040 DOI: 10.1093/nar/gkad252] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 03/23/2023] [Accepted: 04/19/2023] [Indexed: 04/26/2023] Open
Abstract
DNA sequence composition determines the topology and stability of G-quadruplexes (G4s). Bulged G-quadruplex structures (G4-Bs) are a subset of G4s characterized by 3D conformations with bulges. Current search algorithms fail to capture stable G4-B, making their genome-wide study infeasible. Here, we introduced a large family of computationally defined and experimentally verified potential G4-B forming sequences (pG4-BS). We found 478 263 pG4-BS regions that do not overlap 'canonical' G4-forming sequences in the human genome and are preferentially localized in transcription regulatory regions including R-loops and open chromatin. Over 90% of protein-coding genes contain pG4-BS in their promoter or gene body. We observed generally higher pG4-BS content in R-loops and their flanks, longer genes that are associated with brain tissue, immune and developmental processes. Also, the presence of pG4-BS on both template and non-template strands in promoters is associated with oncogenesis, cardiovascular disease and stemness. Our G4-BS models predicted G4-forming ability in vitro with 91.5% accuracy. Analysis of G4-seq and CUT&Tag data strongly supports the existence of G4-BS conformations genome-wide. We reconstructed a novel G4-B 3D structure located in the E2F8 promoter. This study defines a large family of G4-like sequences, offering new insights into the essential biological functions and potential future therapeutic uses of G4-B.
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Affiliation(s)
- Csaba Papp
- Department of Urology, Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Vineeth T Mukundan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Piroon Jenjaroenpun
- Division of Bioinformatics and Data Management for Research, Research Group and Research Network Division, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
- Bioinformatics Institute, A*STAR Biomedical Institutes, Singapore, Singapore
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Ghim Siong Ow
- Bioinformatics Institute, A*STAR Biomedical Institutes, Singapore, Singapore
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
- NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
| | - Vladimir A Kuznetsov
- Department of Urology, Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Bioinformatics Institute, A*STAR Biomedical Institutes, Singapore, Singapore
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Parsa FG, Nobili S, Karimpour M, Aghdaei HA, Nazemalhosseini-Mojarad E, Mini E. Fanconi Anemia Pathway in Colorectal Cancer: A Novel Opportunity for Diagnosis, Prognosis and Therapy. J Pers Med 2022; 12:jpm12030396. [PMID: 35330396 PMCID: PMC8950345 DOI: 10.3390/jpm12030396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 02/07/2023] Open
Abstract
Colorectal cancer (CRC) is the third most commonly diagnosed malignancy and has the second highest mortality rate globally. Thanks to the advent of next-generation sequencing technologies, several novel candidate genes have been proposed for CRC susceptibility. Germline biallelic mutations in one or more of the 22 currently recognized Fanconi anemia (FA) genes have been associated with Fanconi anemia disease, while germline monoallelic mutations, somatic mutations, or the promoter hypermethylation of some FANC genes increases the risk of cancer development, including CRC. The FA pathway is a substantial part of the DNA damage response system that participates in the repair of DNA inter-strand crosslinks through homologous recombination (HR) and protects genome stability via replication fork stabilization, respectively. Recent studies revealed associations between FA gene/protein tumor expression levels (i.e., FANC genes) and CRC progression and drug resistance. Moreover, the FA pathway represents a potential target in the CRC treatment. In fact, FANC gene characteristics may contribute to chemosensitize tumor cells to DNA crosslinking agents such as oxaliplatin and cisplatin besides exploiting the synthetic lethal approach for selective targeting of tumor cells. Hence, this review summarizes the current knowledge on the function of the FA pathway in DNA repair and genomic integrity with a focus on the FANC genes as potential predisposition factors to CRC. We then introduce recent literature that highlights the importance of FANC genes in CRC as promising prognostic and predictive biomarkers for disease management and treatment. Finally, we represent a brief overview of the current knowledge around the FANC genes as synthetic lethal therapeutic targets for precision cancer medicine.
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Affiliation(s)
- Fatemeh Ghorbani Parsa
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran 19857-17413, Iran; (F.G.P.); (H.A.A.)
| | - Stefania Nobili
- Department of Neurosciences, Imaging and Clinical Sciences, University “G. D’Annunzio” Chieti-Pescara, 66100 Chieti, Italy;
- Center for Advanced Studies and Technology (CAST), University “G. D’Annunzio” Chieti-Pescara, 66100 Chieti, Italy
| | - Mina Karimpour
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-154, Iran;
| | - Hamid Asadzadeh Aghdaei
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran 19857-17413, Iran; (F.G.P.); (H.A.A.)
| | - Ehsan Nazemalhosseini-Mojarad
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran 19857-17413, Iran
- Correspondence: (E.N.-M.); (E.M.)
| | - Enrico Mini
- Department of Health Sciences, University of Florence, 50139 Florence, Italy
- DENOTHE Excellence Center, University of Florence, 50139 Florence, Italy
- Correspondence: (E.N.-M.); (E.M.)
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Kim S, Hwang S. G-Quadruplex Matters in Tissue-Specific Tumorigenesis by BRCA1 Deficiency. Genes (Basel) 2022; 13:genes13030391. [PMID: 35327946 PMCID: PMC8948836 DOI: 10.3390/genes13030391] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 12/14/2022] Open
Abstract
How and why distinct genetic alterations, such as BRCA1 mutation, promote tumorigenesis in certain tissues, but not others, remain an important issue in cancer research. The underlying mechanisms may reveal tissue-specific therapeutic vulnerabilities. Although the roles of BRCA1, such as DNA damage repair and stalled fork stabilization, obviously contribute to tumor suppression, these ubiquitously important functions cannot explain tissue-specific tumorigenesis by BRCA1 mutations. Recent advances in our understanding of the cancer genome and fundamental cellular processes on DNA, such as transcription and DNA replication, have provided new insights regarding BRCA1-associated tumorigenesis, suggesting that G-quadruplex (G4) plays a critical role. In this review, we summarize the importance of G4 structures in mutagenesis of the cancer genome and cell type-specific gene regulation, and discuss a recently revealed molecular mechanism of G4/base excision repair (BER)-mediated transcriptional activation. The latter adequately explains the correlation between the accumulation of unresolved transcriptional regulatory G4s and multi-level genomic alterations observed in BRCA1-associated tumors. In summary, tissue-specific tumorigenesis by BRCA1 deficiency can be explained by cell type-specific levels of transcriptional regulatory G4s and the role of BRCA1 in resolving it. This mechanism would provide an integrated understanding of the initiation and development of BRCA1-associated tumors.
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Affiliation(s)
- Sanghyun Kim
- Department of Biomedical Science, College of Life Science, CHA University, Sungnam 13488, Korea;
| | - Sohyun Hwang
- Department of Biomedical Science, College of Life Science, CHA University, Sungnam 13488, Korea;
- Department of Pathology, CHA Bundang Medical Center, CHA University School of Medicine, Sungnam 13496, Korea
- Correspondence:
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Whale AJ, King M, Hull RM, Krueger F, Houseley J. Stimulation of adaptive gene amplification by origin firing under replication fork constraint. Nucleic Acids Res 2022; 50:915-936. [PMID: 35018465 PMCID: PMC8789084 DOI: 10.1093/nar/gkab1257] [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: 03/05/2021] [Revised: 11/26/2021] [Accepted: 12/06/2021] [Indexed: 02/06/2023] Open
Abstract
Adaptive mutations can cause drug resistance in cancers and pathogens, and increase the tolerance of agricultural pests and diseases to chemical treatment. When and how adaptive mutations form is often hard to discern, but we have shown that adaptive copy number amplification of the copper resistance gene CUP1 occurs in response to environmental copper due to CUP1 transcriptional activation. Here we dissect the mechanism by which CUP1 transcription in budding yeast stimulates copy number variation (CNV). We show that transcriptionally stimulated CNV requires TREX-2 and Mediator, such that cells lacking TREX-2 or Mediator respond normally to copper but cannot acquire increased resistance. Mediator and TREX-2 can cause replication stress by tethering transcribed loci to nuclear pores, a process known as gene gating, and transcription at the CUP1 locus causes a TREX-2-dependent accumulation of replication forks indicative of replication fork stalling. TREX-2-dependent CUP1 gene amplification occurs by a Rad52 and Rad51-mediated homologous recombination mechanism that is enhanced by histone H3K56 acetylation and repressed by Pol32 and Pif1. CUP1 amplification is also critically dependent on late-firing replication origins present in the CUP1 repeats, and mutations that remove or inactivate these origins strongly suppress the acquisition of copper resistance. We propose that replicative stress imposed by nuclear pore association causes replication bubbles from these origins to collapse soon after activation, leaving a tract of H3K56-acetylated chromatin that promotes secondary recombination events during elongation after replication fork re-start events. The capacity for inefficient replication origins to promote copy number variation renders certain genomic regions more fragile than others, and therefore more likely to undergo adaptive evolution through de novo gene amplification.
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Affiliation(s)
- Alex J Whale
- Epigenetics Programme, Babraham Institute, Cambridge, UK
| | - Michelle King
- Epigenetics Programme, Babraham Institute, Cambridge, UK
| | - Ryan M Hull
- Epigenetics Programme, Babraham Institute, Cambridge, UK
| | - Felix Krueger
- Babraham Bioinformatics, Babraham Institute, Cambridge, UK
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9
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Akter J, Katai Y, Sultana P, Takenobu H, Haruta M, Sugino RP, Mukae K, Satoh S, Wada T, Ohira M, Ando K, Kamijo T. Loss of p53 suppresses replication stress-induced DNA damage in ATRX-deficient neuroblastoma. Oncogenesis 2021; 10:73. [PMID: 34743173 PMCID: PMC8572175 DOI: 10.1038/s41389-021-00363-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 10/03/2021] [Accepted: 10/11/2021] [Indexed: 11/09/2022] Open
Abstract
Genetic aberrations are present in the ATRX gene in older high-risk neuroblastoma (NB) patients with very poor clinical outcomes. Its loss-of-function (LoF) facilitates the alternative lengthening of telomeres (ALT) pathway in tumor cells and is strongly linked to replication stress (RS) and DNA damage through G-quadruplex (G4) DNA secondary structures. However, limited information is available on ATRX alteration-related NB tumorigenesis. We herein knocked out (KO) ATRX in MYCN-amplified (NGP) and MYCN single copy (SK-N-AS) NB cells with wild-type (wt) and truncated TP53 at the C terminus, respectively, using CRISPR/Cas9 technologies. The loss of ATRX increased DNA damage and G4 formation related to RS in TP53 wt isogenic ATRX KO NGP cells, but not in SK-N-AS clones. A gene set enrichment analysis (GSEA) showed that the gene sets related to DNA double-strand break repair, negative cell cycle regulation, the G2M checkpoint, and p53 pathway activation were enriched in NGP clones. The accumulation of DNA damage activated the ATM/CHK2/p53 pathway, leading to cell cycle arrest in NGP clones. Interestingly, ATRX loss did not induce RS related to DNA damage response (DDR) in TP53-truncated SK-N-AS cells. p53 inactivation abrogated cell cycle arrest and reduced G4 accumulation in NGP clones. The loss of p53 also induced G4 DNA helicases or Fanconi anemia group D2 protein (FANCD2) with ATRX deficiency, suggesting that ATRX maintained genome integrity and p53 deficiency attenuated RS-induced DNA damage in NB cells featuring inactivated ATRX by regulating DNA repair mechanisms and replication fork stability.
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Affiliation(s)
- Jesmin Akter
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Yutaka Katai
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Parvin Sultana
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan.,Laboratory of Tumor Molecular Biology, Department of Graduate School of Science and Engineering, Saitama University, Saitama, Japan
| | - Hisanori Takenobu
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Masayuki Haruta
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Ryuichi P Sugino
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Kyosuke Mukae
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Shunpei Satoh
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Tomoko Wada
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Miki Ohira
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Kiyohiro Ando
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan
| | - Takehiko Kamijo
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama, Japan. .,Laboratory of Tumor Molecular Biology, Department of Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
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10
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Pavlova AV, Kubareva EA, Monakhova MV, Zvereva MI, Dolinnaya NG. Impact of G-Quadruplexes on the Regulation of Genome Integrity, DNA Damage and Repair. Biomolecules 2021; 11:1284. [PMID: 34572497 PMCID: PMC8472537 DOI: 10.3390/biom11091284] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/19/2021] [Accepted: 08/25/2021] [Indexed: 12/13/2022] Open
Abstract
DNA G-quadruplexes (G4s) are known to be an integral part of the complex regulatory systems in both normal and pathological cells. At the same time, the ability of G4s to impede DNA replication plays a critical role in genome integrity. This review summarizes the results of recent studies of G4-mediated genomic and epigenomic instability, together with associated DNA damage and repair processes. Although the underlying mechanisms remain to be elucidated, it is known that, among the proteins that recognize G4 structures, many are linked to DNA repair. We analyzed the possible role of G4s in promoting double-strand DNA breaks, one of the most deleterious DNA lesions, and their repair via error-prone mechanisms. The patterns of G4 damage, with a focus on the introduction of oxidative guanine lesions, as well as their removal from G4 structures by canonical repair pathways, were also discussed together with the effects of G4s on the repair machinery. According to recent findings, there must be a delicate balance between G4-induced genome instability and G4-promoted repair processes. A broad overview of the factors that modulate the stability of G4 structures in vitro and in vivo is also provided here.
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Affiliation(s)
- Anzhela V. Pavlova
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (M.I.Z.); (N.G.D.)
| | - Elena A. Kubareva
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (E.A.K.); (M.V.M.)
| | - Mayya V. Monakhova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (E.A.K.); (M.V.M.)
| | - Maria I. Zvereva
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (M.I.Z.); (N.G.D.)
| | - Nina G. Dolinnaya
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (M.I.Z.); (N.G.D.)
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11
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Uruci S, Lo CSY, Wheeler D, Taneja N. R-Loops and Its Chro-Mates: The Strange Case of Dr. Jekyll and Mr. Hyde. Int J Mol Sci 2021; 22:ijms22168850. [PMID: 34445553 PMCID: PMC8396322 DOI: 10.3390/ijms22168850] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/04/2021] [Accepted: 08/12/2021] [Indexed: 12/22/2022] Open
Abstract
Since their discovery, R-loops have been associated with both physiological and pathological functions that are conserved across species. R-loops are a source of replication stress and genome instability, as seen in neurodegenerative disorders and cancer. In response, cells have evolved pathways to prevent R-loop accumulation as well as to resolve them. A growing body of evidence correlates R-loop accumulation with changes in the epigenetic landscape. However, the role of chromatin modification and remodeling in R-loops homeostasis remains unclear. This review covers various mechanisms precluding R-loop accumulation and highlights the role of chromatin modifiers and remodelers in facilitating timely R-loop resolution. We also discuss the enigmatic role of RNA:DNA hybrids in facilitating DNA repair, epigenetic landscape and the potential role of replication fork preservation pathways, active fork stability and stalled fork protection pathways, in avoiding replication-transcription conflicts. Finally, we discuss the potential role of several Chro-Mates (chromatin modifiers and remodelers) in the likely differentiation between persistent/detrimental R-loops and transient/benign R-loops that assist in various physiological processes relevant for therapeutic interventions.
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Affiliation(s)
- Sidrit Uruci
- Department of Molecular Genetics, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands; (S.U.); (C.S.Y.L.)
| | - Calvin Shun Yu Lo
- Department of Molecular Genetics, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands; (S.U.); (C.S.Y.L.)
| | - David Wheeler
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA;
| | - Nitika Taneja
- Department of Molecular Genetics, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands; (S.U.); (C.S.Y.L.)
- Correspondence:
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12
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Santos T, Salgado GF, Cabrita EJ, Cruz C. G-Quadruplexes and Their Ligands: Biophysical Methods to Unravel G-Quadruplex/Ligand Interactions. Pharmaceuticals (Basel) 2021; 14:769. [PMID: 34451866 PMCID: PMC8401999 DOI: 10.3390/ph14080769] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/31/2021] [Accepted: 08/03/2021] [Indexed: 12/12/2022] Open
Abstract
Progress in the design of G-quadruplex (G4) binding ligands relies on the availability of approaches that assess the binding mode and nature of the interactions between G4 forming sequences and their putative ligands. The experimental approaches used to characterize G4/ligand interactions can be categorized into structure-based methods (circular dichroism (CD), nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography), affinity and apparent affinity-based methods (surface plasmon resonance (SPR), isothermal titration calorimetry (ITC) and mass spectrometry (MS)), and high-throughput methods (fluorescence resonance energy transfer (FRET)-melting, G4-fluorescent intercalator displacement assay (G4-FID), affinity chromatography and microarrays. Each method has unique advantages and drawbacks, which makes it essential to select the ideal strategies for the biological question being addressed. The structural- and affinity and apparent affinity-based methods are in several cases complex and/or time-consuming and can be combined with fast and cheap high-throughput approaches to improve the design and development of new potential G4 ligands. In recent years, the joint use of these techniques permitted the discovery of a huge number of G4 ligands investigated for diagnostic and therapeutic purposes. Overall, this review article highlights in detail the most commonly used approaches to characterize the G4/ligand interactions, as well as the applications and types of information that can be obtained from the use of each technique.
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Affiliation(s)
- Tiago Santos
- CICS-UBI—Centro de Investigação em Ciências da Saúde, Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal;
| | - Gilmar F. Salgado
- ARNA Laboratory, Université de Bordeaux, Inserm U1212, CNRS UMR 5320, IECB, 33607 Pessac, France;
| | - Eurico J. Cabrita
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal;
- Associate Laboratory i4HB—Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal
| | - Carla Cruz
- CICS-UBI—Centro de Investigação em Ciências da Saúde, Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal;
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13
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Dettori LG, Torrejon D, Chakraborty A, Dutta A, Mohamed M, Papp C, Kuznetsov VA, Sung P, Feng W, Bah A. A Tale of Loops and Tails: The Role of Intrinsically Disordered Protein Regions in R-Loop Recognition and Phase Separation. Front Mol Biosci 2021; 8:691694. [PMID: 34179096 PMCID: PMC8222781 DOI: 10.3389/fmolb.2021.691694] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/14/2021] [Indexed: 11/13/2022] Open
Abstract
R-loops are non-canonical, three-stranded nucleic acid structures composed of a DNA:RNA hybrid, a displaced single-stranded (ss)DNA, and a trailing ssRNA overhang. R-loops perform critical biological functions under both normal and disease conditions. To elucidate their cellular functions, we need to understand the mechanisms underlying R-loop formation, recognition, signaling, and resolution. Previous high-throughput screens identified multiple proteins that bind R-loops, with many of these proteins containing folded nucleic acid processing and binding domains that prevent (e.g., topoisomerases), resolve (e.g., helicases, nucleases), or recognize (e.g., KH, RRMs) R-loops. However, a significant number of these R-loop interacting Enzyme and Reader proteins also contain long stretches of intrinsically disordered regions (IDRs). The precise molecular and structural mechanisms by which the folded domains and IDRs synergize to recognize and process R-loops or modulate R-loop-mediated signaling have not been fully explored. While studying one such modular R-loop Reader, the Fragile X Protein (FMRP), we unexpectedly discovered that the C-terminal IDR (C-IDR) of FMRP is the predominant R-loop binding site, with the three N-terminal KH domains recognizing the trailing ssRNA overhang. Interestingly, the C-IDR of FMRP has recently been shown to undergo spontaneous Liquid-Liquid Phase Separation (LLPS) assembly by itself or in complex with another non-canonical nucleic acid structure, RNA G-quadruplex. Furthermore, we have recently shown that FMRP can suppress persistent R-loops that form during transcription, a process that is also enhanced by LLPS via the assembly of membraneless transcription factories. These exciting findings prompted us to explore the role of IDRs in R-loop processing and signaling proteins through a comprehensive bioinformatics and computational biology study. Here, we evaluated IDR prevalence, sequence composition and LLPS propensity for the known R-loop interactome. We observed that, like FMRP, the majority of the R-loop interactome, especially Readers, contains long IDRs that are highly enriched in low complexity sequences with biased amino acid composition, suggesting that these IDRs could directly interact with R-loops, rather than being “mere flexible linkers” connecting the “functional folded enzyme or binding domains”. Furthermore, our analysis shows that several proteins in the R-loop interactome are either predicted to or have been experimentally demonstrated to undergo LLPS or are known to be associated with phase separated membraneless organelles. Thus, our overall results present a thought-provoking hypothesis that IDRs in the R-loop interactome can provide a functional link between R-loop recognition via direct binding and downstream signaling through the assembly of LLPS-mediated membrane-less R-loop foci. The absence or dysregulation of the function of IDR-enriched R-loop interactors can potentially lead to severe genomic defects, such as the widespread R-loop-mediated DNA double strand breaks that we recently observed in Fragile X patient-derived cells.
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Affiliation(s)
- Leonardo G Dettori
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Diego Torrejon
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Arijita Chakraborty
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Arijit Dutta
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX, United States
| | - Mohamed Mohamed
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Csaba Papp
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, United States.,Department of Urology, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Vladimir A Kuznetsov
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY, United States.,Bioinformatics Institute, ASTAR Biomedical Institutes, Singapore, Singapore
| | - Patrick Sung
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX, United States
| | - Wenyi Feng
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Alaji Bah
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, United States
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14
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Wang Y, Chen Y, Wang C, Yang M, Wang Y, Bao L, Wang JE, Kim B, Chan KY, Xu W, Capota E, Ortega J, Nijhawan D, Li GM, Luo W, Wang Y. MIF is a 3' flap nuclease that facilitates DNA replication and promotes tumor growth. Nat Commun 2021; 12:2954. [PMID: 34012010 PMCID: PMC8134555 DOI: 10.1038/s41467-021-23264-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 04/20/2021] [Indexed: 11/13/2022] Open
Abstract
How cancer cells cope with high levels of replication stress during rapid proliferation is currently unclear. Here, we show that macrophage migration inhibitory factor (MIF) is a 3’ flap nuclease that translocates to the nucleus in S phase. Poly(ADP-ribose) polymerase 1 co-localizes with MIF to the DNA replication fork, where MIF nuclease activity is required to resolve replication stress and facilitates tumor growth. MIF loss in cancer cells leads to mutation frequency increases, cell cycle delays and DNA synthesis and cell growth inhibition, which can be rescued by restoring MIF, but not nuclease-deficient MIF mutant. MIF is significantly upregulated in breast tumors and correlates with poor overall survival in patients. We propose that MIF is a unique 3’ nuclease, excises flaps at the immediate 3’ end during DNA synthesis and favors cancer cells evading replication stress-induced threat for their growth. Replication stress is associated with cancer formation and progression. Here the authors reveal that the macrophage migration inhibitory factor (MIF) functions as 3’ flap nuclease involved in resolving replication stress affecting overall tumor progression.
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Affiliation(s)
- Yijie Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yan Chen
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Chenliang Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Mingming Yang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yanan Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Lei Bao
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jennifer E Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - BongWoo Kim
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Kara Y Chan
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Weizhi Xu
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Emanuela Capota
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA
| | - Janice Ortega
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Deepak Nijhawan
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA
| | - Guo-Min Li
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Weibo Luo
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yingfei Wang
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA. .,Department of Neurology, UT Southwestern Medical Center, Dallas, TX, USA.
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15
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Single-molecule imaging reveals replication fork coupled formation of G-quadruplex structures hinders local replication stress signaling. Nat Commun 2021; 12:2525. [PMID: 33953191 PMCID: PMC8099879 DOI: 10.1038/s41467-021-22830-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 03/30/2021] [Indexed: 12/19/2022] Open
Abstract
Guanine-rich DNA sequences occur throughout the human genome and can transiently form G-quadruplex (G4) structures that may obstruct DNA replication, leading to genomic instability. Here, we apply multi-color single-molecule localization microscopy (SMLM) coupled with robust data-mining algorithms to quantitatively visualize replication fork (RF)-coupled formation and spatial-association of endogenous G4s. Using this data, we investigate the effects of G4s on replisome dynamics and organization. We show that a small fraction of active replication forks spontaneously form G4s at newly unwound DNA immediately behind the MCM helicase and before nascent DNA synthesis. These G4s locally perturb replisome dynamics and organization by reducing DNA synthesis and limiting the binding of the single-strand DNA-binding protein RPA. We find that the resolution of RF-coupled G4s is mediated by an interplay between RPA and the FANCJ helicase. FANCJ deficiency leads to G4 accumulation, DNA damage at G4-associated replication forks, and silencing of the RPA-mediated replication stress response. Our study provides first-hand evidence of the intrinsic, RF-coupled formation of G4 structures, offering unique mechanistic insights into the interference and regulation of stable G4s at replication forks and their effect on RPA-associated fork signaling and genomic instability.
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16
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Willaume S, Rass E, Fontanilla-Ramirez P, Moussa A, Wanschoor P, Bertrand P. A Link between Replicative Stress, Lamin Proteins, and Inflammation. Genes (Basel) 2021; 12:genes12040552. [PMID: 33918867 PMCID: PMC8070205 DOI: 10.3390/genes12040552] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/23/2021] [Accepted: 04/08/2021] [Indexed: 12/12/2022] Open
Abstract
Double-stranded breaks (DSB), the most toxic DNA lesions, are either a consequence of cellular metabolism, programmed as in during V(D)J recombination, or induced by anti-tumoral therapies or accidental genotoxic exposure. One origin of DSB sources is replicative stress, a major source of genome instability, especially when the integrity of the replication forks is not properly guaranteed. To complete stalled replication, restarting the fork requires complex molecular mechanisms, such as protection, remodeling, and processing. Recently, a link has been made between DNA damage accumulation and inflammation. Indeed, defects in DNA repair or in replication can lead to the release of DNA fragments in the cytosol. The recognition of this self-DNA by DNA sensors leads to the production of inflammatory factors. This beneficial response activating an innate immune response and destruction of cells bearing DNA damage may be considered as a novel part of DNA damage response. However, upon accumulation of DNA damage, a chronic inflammatory cellular microenvironment may lead to inflammatory pathologies, aging, and progression of tumor cells. Progress in understanding the molecular mechanisms of DNA damage repair, replication stress, and cytosolic DNA production would allow to propose new therapeutical strategies against cancer or inflammatory diseases associated with aging. In this review, we describe the mechanisms involved in DSB repair, the replicative stress management, and its consequences. We also focus on new emerging links between key components of the nuclear envelope, the lamins, and DNA repair, management of replicative stress, and inflammation.
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17
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Origin, Regulation, and Fitness Effect of Chromosomal Rearrangements in the Yeast Saccharomyces cerevisiae. Int J Mol Sci 2021; 22:ijms22020786. [PMID: 33466757 PMCID: PMC7830279 DOI: 10.3390/ijms22020786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/02/2021] [Accepted: 01/11/2021] [Indexed: 11/16/2022] Open
Abstract
Chromosomal rearrangements comprise unbalanced structural variations resulting in gain or loss of DNA copy numbers, as well as balanced events including translocation and inversion that are copy number neutral, both of which contribute to phenotypic evolution in organisms. The exquisite genetic assay and gene editing tools available for the model organism Saccharomyces cerevisiae facilitate deep exploration of the mechanisms underlying chromosomal rearrangements. We discuss here the pathways and influential factors of chromosomal rearrangements in S. cerevisiae. Several methods have been developed to generate on-demand chromosomal rearrangements and map the breakpoints of rearrangement events. Finally, we highlight the contributions of chromosomal rearrangements to drive phenotypic evolution in various S. cerevisiae strains. Given the evolutionary conservation of DNA replication and recombination in organisms, the knowledge gathered in the small genome of yeast can be extended to the genomes of higher eukaryotes.
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18
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Miglietta G, Russo M, Capranico G. G-quadruplex-R-loop interactions and the mechanism of anticancer G-quadruplex binders. Nucleic Acids Res 2020; 48:11942-11957. [PMID: 33137181 PMCID: PMC7708042 DOI: 10.1093/nar/gkaa944] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/05/2020] [Accepted: 10/08/2020] [Indexed: 12/17/2022] Open
Abstract
Genomic DNA and cellular RNAs can form a variety of non-B secondary structures, including G-quadruplex (G4) and R-loops. G4s are constituted by stacked guanine tetrads held together by Hoogsteen hydrogen bonds and can form at key regulatory sites of eukaryote genomes and transcripts, including gene promoters, untranslated exon regions and telomeres. R-loops are 3-stranded structures wherein the two strands of a DNA duplex are melted and one of them is annealed to an RNA. Specific G4 binders are intensively investigated to discover new effective anticancer drugs based on a common rationale, i.e.: the selective inhibition of oncogene expression or specific impairment of telomere maintenance. However, despite the high number of known G4 binders, such a selective molecular activity has not been fully established and several published data point to a different mode of action. We will review published data that address the close structural interplay between G4s and R-loops in vitro and in vivo, and how these interactions can have functional consequences in relation to G4 binder activity. We propose that R-loops can play a previously-underestimated role in G4 binder action, in relation to DNA damage induction, telomere maintenance, genome and epigenome instability and alterations of gene expression programs.
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Affiliation(s)
- Giulia Miglietta
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126 Bologna, Italy
| | - Marco Russo
- 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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19
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Xu YZ, Jenjaroenpun P, Wongsurawat T, Byrum SD, Shponka V, Tannahill D, Chavez EA, Hung SS, Steidl C, Balasubramanian S, Rimsza LM, Kendrick S. Activation-induced cytidine deaminase localizes to G-quadruplex motifs at mutation hotspots in lymphoma. NAR Cancer 2020; 2:zcaa029. [PMID: 33094287 PMCID: PMC7556405 DOI: 10.1093/narcan/zcaa029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/31/2020] [Accepted: 09/29/2020] [Indexed: 01/03/2023] Open
Abstract
Diffuse large B-cell lymphoma (DLBCL) is a molecularly heterogeneous group of malignancies with frequent genetic abnormalities. G-quadruplex (G4) DNA structures may facilitate this genomic instability through association with activation-induced cytidine deaminase (AID), an antibody diversification enzyme implicated in mutation of oncogenes in B-cell lymphomas. Chromatin immunoprecipitation sequencing analyses in this study revealed that AID hotspots in both activated B cells and lymphoma cells in vitro were highly enriched for G4 elements. A representative set of these targeted sequences was validated for characteristic, stable G4 structure formation including previously unknown G4s in lymphoma-associated genes, CBFA2T3, SPIB, BCL6, HLA-DRB5 and MEF2C, along with the established BCL2 and MYC structures. Frequent genome-wide G4 formation was also detected for the first time in DLBCL patient-derived tissues using BG4, a structure-specific G4 antibody. Tumors with greater staining were more likely to have concurrent BCL2 and MYC oncogene amplification and BCL2 mutations. Ninety-seven percent of the BCL2 mutations occurred within G4 sites that overlapped with AID binding. G4 localization at sites of mutation, and within aggressive DLBCL tumors harboring amplified BCL2 and MYC, supports a role for G4 structures in events that lead to a loss of genomic integrity, a critical step in B-cell lymphomagenesis.
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Affiliation(s)
- Ying-Zhi Xu
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Piroon Jenjaroenpun
- Department of Bioinformatics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Division of Bioinformatics and Data Management for Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Thidathip Wongsurawat
- Department of Bioinformatics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Division of Bioinformatics and Data Management for Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Stephanie D Byrum
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Volodymyr Shponka
- Department of Pathology, University of Arizona, Tucson, AZ 85721, USA
| | - David Tannahill
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, UK
| | | | - Stacy S Hung
- British Columbia Cancer Agency, Vancouver, BC V5Z 1L3, Canada
| | | | - Shankar Balasubramanian
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, UK
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Lisa M Rimsza
- Laboratory Medicine and Pathology, Mayo Clinic, Scottsdale, AZ 85259, USA
| | - Samantha Kendrick
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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20
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Timpano S, Picketts DJ. Neurodevelopmental Disorders Caused by Defective Chromatin Remodeling: Phenotypic Complexity Is Highlighted by a Review of ATRX Function. Front Genet 2020; 11:885. [PMID: 32849845 PMCID: PMC7432156 DOI: 10.3389/fgene.2020.00885] [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: 06/07/2020] [Accepted: 07/20/2020] [Indexed: 12/15/2022] Open
Abstract
The ability to determine the genetic etiology of intellectual disability (ID) and neurodevelopmental disorders (NDD) has improved immensely over the last decade. One prevailing metric from these studies is the large percentage of genes encoding epigenetic regulators, including many members of the ATP-dependent chromatin remodeling enzyme family. Chromatin remodeling proteins can be subdivided into five classes that include SWI/SNF, ISWI, CHD, INO80, and ATRX. These proteins utilize the energy from ATP hydrolysis to alter nucleosome positioning and are implicated in many cellular processes. As such, defining their precise roles and contributions to brain development and disease pathogenesis has proven to be complex. In this review, we illustrate that complexity by reviewing the roles of ATRX on genome stability, replication, and transcriptional regulation and how these mechanisms provide key insight into the phenotype of ATR-X patients.
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Affiliation(s)
- Sara Timpano
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - David J Picketts
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada.,Department of Medicine, University of Ottawa, Ottawa, ON, Canada.,University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada
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21
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Zhang J, Bellani MA, James RC, Pokharel D, Zhang Y, Reynolds JJ, McNee GS, Jackson AP, Stewart GS, Seidman MM. DONSON and FANCM associate with different replisomes distinguished by replication timing and chromatin domain. Nat Commun 2020; 11:3951. [PMID: 32769987 PMCID: PMC7414851 DOI: 10.1038/s41467-020-17449-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 06/30/2020] [Indexed: 12/11/2022] Open
Abstract
Duplication of mammalian genomes requires replisomes to overcome numerous impediments during passage through open (eu) and condensed (hetero) chromatin. Typically, studies of replication stress characterize mixed populations of challenged and unchallenged replication forks, averaged across S phase, and model a single species of “stressed” replisome. Here, in cells containing potent obstacles to replication, we find two different lesion proximal replisomes. One is bound by the DONSON protein and is more frequent in early S phase, in regions marked by euchromatin. The other interacts with the FANCM DNA translocase, is more prominent in late S phase, and favors heterochromatin. The two forms can also be detected in unstressed cells. ChIP-seq of DNA associated with DONSON or FANCM confirms the bias of the former towards regions that replicate early and the skew of the latter towards regions that replicate late. Eukaryotic replisomes are multiprotein complexes. Here the authors reveal two distinct stressed replisomes, associated with DONSON and FANCM, displaying a bias in replication timing and chromatin domain.
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Affiliation(s)
- Jing Zhang
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Marina A Bellani
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Ryan C James
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14850, USA
| | | | - Yongqing Zhang
- Gene Expression and Genomics Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - John J Reynolds
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Gavin S McNee
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Andrew P Jackson
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Grant S Stewart
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Michael M Seidman
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA.
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22
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The integrated stress response induces R-loops and hinders replication fork progression. Cell Death Dis 2020; 11:538. [PMID: 32678076 PMCID: PMC7366693 DOI: 10.1038/s41419-020-2727-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 06/25/2020] [Indexed: 12/15/2022]
Abstract
The integrated stress response (ISR) allows cells to rapidly shutdown most of their protein synthesis in response to protein misfolding, amino acid deficiency, or virus infection. These stresses trigger the phosphorylation of the translation initiation factor eIF2alpha, which prevents the initiation of translation. Here we show that triggering the ISR drastically reduces the progression of DNA replication forks within 1 h, thus flanking the shutdown of protein synthesis with immediate inhibition of DNA synthesis. DNA replication is restored by compounds that inhibit eIF2alpha kinases or re-activate eIF2alpha. Mechanistically, the translational shutdown blocks histone synthesis, promoting the formation of DNA:RNA hybrids (R-loops), which interfere with DNA replication. R-loops accumulate upon histone depletion. Conversely, histone overexpression or R-loop removal by RNaseH1 each restores DNA replication in the context of ISR and histone depletion. In conclusion, the ISR rapidly stalls DNA synthesis through histone deficiency and R-loop formation. We propose that this shutdown mechanism prevents potentially detrimental DNA replication in the face of cellular stresses.
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