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Jin C, Einig E, Xu W, Kollampally RB, Schlosser A, Flentje M, Popov N. The dimeric deubiquitinase USP28 integrates 53BP1 and MYC functions to limit DNA damage. Nucleic Acids Res 2024; 52:3011-3030. [PMID: 38227944 PMCID: PMC11024517 DOI: 10.1093/nar/gkae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 12/21/2023] [Accepted: 01/04/2024] [Indexed: 01/18/2024] Open
Abstract
DNA replication is a major source of endogenous DNA damage in tumor cells and a key target of cellular response to genotoxic stress. DNA replication can be deregulated by oncoproteins, such as transcription factor MYC, aberrantly activated in many human cancers. MYC is stringently regulated by the ubiquitin system - for example, ubiquitination controls recruitment of the elongation factor PAF1c, instrumental in MYC activity. Curiously, a key MYC-targeting deubiquitinase USP28 also controls cellular response to DNA damage via the mediator protein 53BP1. USP28 forms stable dimers, but the biological role of USP28 dimerization is unknown. We show here that dimerization limits USP28 activity and restricts recruitment of PAF1c by MYC. Expression of monomeric USP28 stabilizes MYC and promotes PAF1c recruitment, leading to ectopic DNA synthesis and replication-associated DNA damage. USP28 dimerization is stimulated by 53BP1, which selectively binds USP28 dimers. Genotoxic stress diminishes 53BP1-USP28 interaction, promotes disassembly of USP28 dimers and stimulates PAF1c recruitment by MYC. This triggers firing of DNA replication origins during early response to genotoxins and exacerbates DNA damage. We propose that dimerization of USP28 prevents ectopic DNA replication at transcriptionally active chromatin to maintain genome stability.
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Affiliation(s)
- Chao Jin
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Müller-Str 14, 72076 Tübingen, Germany
- DFG Cluster of Excellence 2180 ‘Image-guided and Functionally Instructed Tumor Therapies’ (iFIT), University of Tübingen, Tübingen, Germany
| | - Elias Einig
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Müller-Str 14, 72076 Tübingen, Germany
- DFG Cluster of Excellence 2180 ‘Image-guided and Functionally Instructed Tumor Therapies’ (iFIT), University of Tübingen, Tübingen, Germany
| | - Wenshan Xu
- Department of Radiation Oncology, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080 Würzburg, Germany
| | - Ravi Babu Kollampally
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Müller-Str 14, 72076 Tübingen, Germany
- DFG Cluster of Excellence 2180 ‘Image-guided and Functionally Instructed Tumor Therapies’ (iFIT), University of Tübingen, Tübingen, Germany
| | - Andreas Schlosser
- Rudolf Virchow Center, Center for Integrative and Translational Bioimaging, University of Würzburg, Josef-Schneider-Str 2, 97080 Würzburg, Germany
| | - Michael Flentje
- Department of Radiation Oncology, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080 Würzburg, Germany
| | - Nikita Popov
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Müller-Str 14, 72076 Tübingen, Germany
- DFG Cluster of Excellence 2180 ‘Image-guided and Functionally Instructed Tumor Therapies’ (iFIT), University of Tübingen, Tübingen, Germany
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2
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Chakraborty P, Magnuson T. INO80 regulates chromatin accessibility to facilitate suppression of sex-linked gene expression during mouse spermatogenesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.04.522761. [PMID: 36711658 PMCID: PMC9881943 DOI: 10.1101/2023.01.04.522761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The INO80 protein is the main catalytic subunit of the INO80-chromatin remodeling complex, which is critical for DNA repair and transcription regulation in murine spermatocytes. In this study, we explored the role of INO80 in silencing genes on meiotic sex chromosomes in male mice. INO80 immunolocalization at the XY body in pachytene spermatocytes suggested a role for INO80 in the meiotic sex body. Subsequent deletion of Ino80 resulted in high expression of sex-linked genes. Furthermore, the active form of RNA polymerase II at the sex body of Ino80 -null pachytene spermatocytes indicates incomplete inactivation of sex-linked genes. A reduction in the recruitment of initiators of meiotic sex chromosome inhibition (MSCI) argues for INO80-facilitated recruitment of DNA repair factors required for silencing sex-linked genes. This role of INO80 is independent of a common INO80 target H2A.Z. Instead, in the absence of INO80, a reduction in chromatin accessibility at DNA repair sites occurs on the sex chromosomes. These data suggest a role for INO80 in DNA repair factor localization, thereby facilitating the silencing of sex-linked genes during the onset of pachynema. Summary Statement Chromatin accessibility and DNA repair factor localization at the sex chromosomes are facilitated by INO80, which regulates sex-linked gene silencing during meiotic progression in spermatocytes.
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Gaballa A, Gebhardt-Wolf A, Krenz B, Mattavelli G, John M, Cossa G, Andreani S, Schülein-Völk C, Montesinos F, Vidal R, Kastner C, Ade CP, Kneitz B, Gasteiger G, Gallant P, Rosenfeldt M, Riedel A, Eilers M. PAF1c links S-phase progression to immune evasion and MYC function in pancreatic carcinoma. Nat Commun 2024; 15:1446. [PMID: 38365788 PMCID: PMC10873513 DOI: 10.1038/s41467-024-45760-8] [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: 09/23/2023] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
In pancreatic ductal adenocarcinoma (PDAC), endogenous MYC is required for S-phase progression and escape from immune surveillance. Here we show that MYC in PDAC cells is needed for the recruitment of the PAF1c transcription elongation complex to RNA polymerase and that depletion of CTR9, a PAF1c subunit, enables long-term survival of PDAC-bearing mice. PAF1c is largely dispensable for normal proliferation and regulation of MYC target genes. Instead, PAF1c limits DNA damage associated with S-phase progression by being essential for the expression of long genes involved in replication and DNA repair. Surprisingly, the survival benefit conferred by CTR9 depletion is not due to DNA damage, but to T-cell activation and restoration of immune surveillance. This is because CTR9 depletion releases RNA polymerase and elongation factors from the body of long genes and promotes the transcription of short genes, including MHC class I genes. The data argue that functionally distinct gene sets compete for elongation factors and directly link MYC-driven S-phase progression to tumor immune evasion.
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Affiliation(s)
- Abdallah Gaballa
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Anneli Gebhardt-Wolf
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Bastian Krenz
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Greta Mattavelli
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Mara John
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Giacomo Cossa
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Silvia Andreani
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Christina Schülein-Völk
- Core Unit High-Content Microscopy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Francisco Montesinos
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Raphael Vidal
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Carolin Kastner
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Carsten P Ade
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Burkhard Kneitz
- Department of Urology and Pediatric Urology, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Georg Gasteiger
- Würzburg Institute of Systems Immunology, Max Planck Research Group, Julius Maximilian University Würzburg, Versbacher Str. 9, 97078, Würzburg, Germany
| | - Peter Gallant
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Mathias Rosenfeldt
- Institute of Pathology, Julius Maximilian University Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Angela Riedel
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Martin Eilers
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany.
- Comprehensive Cancer Center Mainfranken, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany.
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Fenstermaker TK, Petruk S, Mazo A. An emerging paradigm in epigenetic marking: coordination of transcription and replication. Transcription 2024; 15:22-37. [PMID: 38378467 DOI: 10.1080/21541264.2024.2316965] [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: 12/22/2023] [Accepted: 02/06/2024] [Indexed: 02/22/2024] Open
Abstract
DNA replication and RNA transcription both utilize DNA as a template and therefore need to coordinate their activities. The predominant theory in the field is that in order for the replication fork to proceed, transcription machinery has to be evicted from DNA until replication is complete. If that does not occur, these machineries collide, and these collisions elicit various repair mechanisms which require displacement of one of the enzymes, often RNA polymerase, in order for replication to proceed. This model is also at the heart of the epigenetic bookmarking theory, which implies that displacement of RNA polymerase during replication requires gradual re-building of chromatin structure, which guides recruitment of transcriptional proteins and resumption of transcription. We discuss these theories but also bring to light newer data that suggest that these two processes may not be as detrimental to one another as previously thought. This includes findings suggesting that these processes can occur without fork collapse and that RNA polymerase may only be transiently displaced during DNA replication. We discuss potential mechanisms by which RNA polymerase may be retained at the replication fork and quickly rebind to DNA post-replication. These discoveries are important, not only as new evidence as to how these two processes are able to occur harmoniously but also because they have implications on how transcriptional programs are maintained through DNA replication. To this end, we also discuss the coordination of replication and transcription in light of revising the current epigenetic bookmarking theory of how the active gene status can be transmitted through S phase.
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Affiliation(s)
- Tyler K Fenstermaker
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Svetlana Petruk
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Alexander Mazo
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
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5
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Ramos-Alonso L, Chymkowitch P. Maintaining transcriptional homeostasis during cell cycle. Transcription 2024; 15:1-21. [PMID: 37655806 PMCID: PMC11093055 DOI: 10.1080/21541264.2023.2246868] [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: 06/21/2023] [Revised: 07/31/2023] [Accepted: 08/03/2023] [Indexed: 09/02/2023] Open
Abstract
The preservation of gene expression patterns that define cellular identity throughout the cell division cycle is essential to perpetuate cellular lineages. However, the progression of cells through different phases of the cell cycle severely disrupts chromatin accessibility, epigenetic marks, and the recruitment of transcriptional regulators. Notably, chromatin is transiently disassembled during S-phase and undergoes drastic condensation during mitosis, which is a significant challenge to the preservation of gene expression patterns between cell generations. This article delves into the specific gene expression and chromatin regulatory mechanisms that facilitate the preservation of transcriptional identity during replication and mitosis. Furthermore, we emphasize our recent findings revealing the unconventional role of yeast centromeres and mitotic chromosomes in maintaining transcriptional fidelity beyond mitosis.
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Affiliation(s)
- Lucía Ramos-Alonso
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
| | - Pierre Chymkowitch
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
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6
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Zhang S, Liu Y, Sun Y, Liu Q, Gu Y, Huang Y, Zeng Z, Tang F, Ouyang Y. Aberrant R-loop-mediated immune evasion, cellular communication, and metabolic reprogramming affect cancer progression: a single-cell analysis. Mol Cancer 2024; 23:11. [PMID: 38200551 PMCID: PMC10777569 DOI: 10.1186/s12943-023-01924-6] [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: 07/13/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
Dysregulation of R-loop homeostasis is closely related to various human diseases, including cancer. However, the causality of aberrant R-loops in tumor progression remains unclear. In this study, using single-cell RNA-sequencing datasets from lung adenocarcinoma (LUAD), we constructed an R-loop scoring model to characterize the R-loop state according to the identified R-loop regulators related to EGFR mutations, tissue origins, and TNM stage. We then evaluated the relationships of the R-loop score with the tumor microenvironment (TME) and treatment response. Furthermore, the potential roles of FANCI-mediated R-loops in LUAD were explored using a series of in vitro experiments. Results showed that malignant cells with low R-loop scores displayed glycolysis and epithelial-mesenchymal transition pathway activation and immune escape promotion, thereby hampering the antitumor therapeutic effects. Cell communication analysis suggested that low R-loop scores contributed to T cell exhaustion. We subsequently validated the prognostic value of R-loop scores by using bulk transcriptome datasets across 33 tumor types. The R-loop scoring model well predicted patients' therapeutic response to targeted therapy, chemotherapy, or immunotherapy in 32 independent cohorts. Remarkably, changes in R-loop distribution mediated by FANCI deficiency blocked the activity of Ras signaling pathway, suppressing tumor-cell proliferation and dissemination. In conclusion, this study reveals the underlying molecular mechanism of metabolic reprogramming and T cell exhaustion under R-loop score patterns, and the changes in R-loops mediated by R-loop regulators resulting in tumor progression. Therefore, incorporating anticancer methods based on R-loop or R-loop regulators into the treatment schemes of precision medicine may be beneficial.
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Affiliation(s)
- Shichao Zhang
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Engineering Research Center of Cellular Immunotherapy of Guizhou Province, Guizhou Medical University, Guiyang, China
| | - Yang Liu
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Engineering Research Center of Cellular Immunotherapy of Guizhou Province, Guizhou Medical University, Guiyang, China
| | - Yichi Sun
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Engineering Research Center of Cellular Immunotherapy of Guizhou Province, Guizhou Medical University, Guiyang, China
| | - Qin Liu
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Engineering Research Center of Cellular Immunotherapy of Guizhou Province, Guizhou Medical University, Guiyang, China
| | - Yan Gu
- Immune Cells and Antibody Engineering Research Center of Guizhou Province, Key Laboratory of Biology and Medical Engineering, Guizhou Medical University, Guiyang, China
| | - Ya Huang
- Immune Cells and Antibody Engineering Research Center of Guizhou Province, Key Laboratory of Biology and Medical Engineering, Guizhou Medical University, Guiyang, China
| | - Zhu Zeng
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Engineering Research Center of Cellular Immunotherapy of Guizhou Province, Guizhou Medical University, Guiyang, China.
| | - Fuzhou Tang
- Immune Cells and Antibody Engineering Research Center of Guizhou Province, Key Laboratory of Biology and Medical Engineering, Guizhou Medical University, Guiyang, China.
| | - Yan Ouyang
- Immune Cells and Antibody Engineering Research Center of Guizhou Province, Key Laboratory of Biology and Medical Engineering, Guizhou Medical University, Guiyang, China.
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7
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Kumar C, Remus D. Looping out of control: R-loops in transcription-replication conflict. Chromosoma 2024; 133:37-56. [PMID: 37419963 PMCID: PMC10771546 DOI: 10.1007/s00412-023-00804-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/09/2023]
Abstract
Transcription-replication conflict is a major cause of replication stress that arises when replication forks collide with the transcription machinery. Replication fork stalling at sites of transcription compromises chromosome replication fidelity and can induce DNA damage with potentially deleterious consequences for genome stability and organismal health. The block to DNA replication by the transcription machinery is complex and can involve stalled or elongating RNA polymerases, promoter-bound transcription factor complexes, or DNA topology constraints. In addition, studies over the past two decades have identified co-transcriptional R-loops as a major source for impairment of DNA replication forks at active genes. However, how R-loops impede DNA replication at the molecular level is incompletely understood. Current evidence suggests that RNA:DNA hybrids, DNA secondary structures, stalled RNA polymerases, and condensed chromatin states associated with R-loops contribute to the of fork progression. Moreover, since both R-loops and replication forks are intrinsically asymmetric structures, the outcome of R-loop-replisome collisions is influenced by collision orientation. Collectively, the data suggest that the impact of R-loops on DNA replication is highly dependent on their specific structural composition. Here, we will summarize our current understanding of the molecular basis for R-loop-induced replication fork progression defects.
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Affiliation(s)
- Charanya Kumar
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, USA
| | - Dirk Remus
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, USA.
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8
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Heuzé J, Kemiha S, Barthe A, Vilarrubias AT, Aouadi E, Aiello U, Libri D, Lin Y, Lengronne A, Poli J, Pasero P. RNase H2 degrades toxic RNA:DNA hybrids behind stalled forks to promote replication restart. EMBO J 2023; 42:e113104. [PMID: 37855233 PMCID: PMC10690446 DOI: 10.15252/embj.2022113104] [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: 11/20/2022] [Revised: 09/27/2023] [Accepted: 10/04/2023] [Indexed: 10/20/2023] Open
Abstract
R-loops represent a major source of replication stress, but the mechanism by which these structures impede fork progression remains unclear. To address this question, we monitored fork progression, arrest, and restart in Saccharomyces cerevisiae cells lacking RNase H1 and H2, two enzymes responsible for degrading RNA:DNA hybrids. We found that while RNase H-deficient cells could replicate their chromosomes normally under unchallenged growth conditions, their replication was impaired when exposed to hydroxyurea (HU) or methyl methanesulfonate (MMS). Treated cells exhibited increased levels of RNA:DNA hybrids at stalled forks and were unable to generate RPA-coated single-stranded (ssDNA), an important postreplicative intermediate in resuming replication. Similar impairments in nascent DNA resection and ssDNA formation at HU-arrested forks were observed in human cells lacking RNase H2. However, fork resection was fully restored by addition of triptolide, an inhibitor of transcription that induces RNA polymerase degradation. Taken together, these data indicate that RNA:DNA hybrids not only act as barriers to replication forks, but also interfere with postreplicative fork repair mechanisms if not promptly degraded by RNase H.
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Affiliation(s)
- Jonathan Heuzé
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
| | - Samira Kemiha
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
| | - Antoine Barthe
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
| | - Alba Torán Vilarrubias
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
| | - Elyès Aouadi
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
| | - Umberto Aiello
- Université Paris Cité, CNRS, Institut Jacques MonodParisFrance
- Department of GeneticsStanford UniversityStanfordCAUSA
| | - Domenico Libri
- Université Paris Cité, CNRS, Institut Jacques MonodParisFrance
- Present address:
Institut de Génétique Moléculaire de MontpellierUniversité de Montpellier, CNRSMontpellierFrance
| | - Yea‐Lih Lin
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
| | - Armelle Lengronne
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
| | - Jérôme Poli
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
- Institut Universitaire de France (IUF)ParisFrance
| | - Philippe Pasero
- Institut de Génétique HumaineUniversité de Montpellier, CNRS, Equipe labélisée Ligue contre le CancerMontpellierFrance
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9
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Abstract
Transcription and replication both require large macromolecular complexes to act on a DNA template, yet these machineries cannot simultaneously act on the same DNA sequence. Conflicts between the replication and transcription machineries (transcription-replication conflicts, or TRCs) are widespread in both prokaryotes and eukaryotes and have the capacity to both cause DNA damage and compromise complete, faithful replication of the genome. This review will highlight recent studies investigating the genomic locations of TRCs and the mechanisms by which they may be prevented, mitigated, or resolved. We address work from both model organisms and mammalian systems but predominantly focus on multicellular eukaryotes owing to the additional complexities inherent in the coordination of replication and transcription in the context of cell type-specific gene expression and higher-order chromatin organization.
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Affiliation(s)
- Liana Goehring
- Department of Biochemistry & Molecular Pharmacology, New York University School of Medicine, New York, NY, USA;
| | - Tony T Huang
- Department of Biochemistry & Molecular Pharmacology, New York University School of Medicine, New York, NY, USA;
| | - Duncan J Smith
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA;
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10
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Heuzé J, Lin YL, Lengronne A, Poli J, Pasero P. Impact of R-loops on oncogene-induced replication stress in cancer cells. C R Biol 2023; 346:95-105. [PMID: 37779381 DOI: 10.5802/crbiol.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 07/19/2023] [Accepted: 07/20/2023] [Indexed: 10/03/2023]
Abstract
Replication stress is an alteration in the progression of replication forks caused by a variety of events of endogenous or exogenous origin. In precancerous lesions, this stress is exacerbated by the deregulation of oncogenic pathways, which notably disrupts the coordination between replication and transcription, and leads to genetic instability and cancer development. It is now well established that transcription can interfere with genome replication in different ways, such as head-on collisions between polymerases, accumulation of positive DNA supercoils or formation of R-loops. These structures form during transcription when nascent RNA reanneals with DNA behind the RNA polymerase, forming a stable DNA:RNA hybrid. In this review, we discuss how these different cotranscriptional processes disrupt the progression of replication forks and how they contribute to genetic instability in cancer cells.
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11
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Reese JC. New roles for elongation factors in RNA polymerase II ubiquitylation and degradation. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2023; 1866:194956. [PMID: 37331651 PMCID: PMC10527621 DOI: 10.1016/j.bbagrm.2023.194956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 06/07/2023] [Accepted: 06/13/2023] [Indexed: 06/20/2023]
Abstract
RNA polymerase II (RNAPII) encounters numerous impediments on its way to completing mRNA synthesis across a gene. Paused and arrested RNAPII are reactivated or rescued by elongation factors that travel with polymerase as it transcribes DNA. However, when RNAPII fails to resume transcription, such as when it encounters an unrepairable bulky DNA lesion, it is removed by the targeting of its largest subunit, Rpb1, for degradation by the ubiquitin-proteasome system (UPS). We are starting to understand this process better and how the UPS marks Rbp1 for degradation. This review will focus on the latest developments and describe new functions for elongation factors that were once thought to only promote elongation in unstressed conditions in the removal and degradation of RNAPII. I propose that in addition to changes in RNAPII structure, the composition and modification of elongation factors in the elongation complex determine whether to rescue or degrade RNAPII.
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Affiliation(s)
- Joseph C Reese
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA.
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12
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Yates LA, Zhang X. Phosphoregulation of the checkpoint kinase Mec1 ATR. DNA Repair (Amst) 2023; 129:103543. [PMID: 37480741 DOI: 10.1016/j.dnarep.2023.103543] [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: 07/05/2023] [Revised: 07/14/2023] [Accepted: 07/15/2023] [Indexed: 07/24/2023]
Abstract
Yeast Mec1, and its mammalian ortholog, Ataxia-Telangiectasia and Rad3-related, are giant protein kinases central to replication stress and double strand DNA break repair. Mec1ATR, in complex with Ddc2ATRIP, is a 'sensor' of single stranded DNA, and phosphorylates numerous cell cycle and DNA repair factors to enforce cell cycle arrest and facilitate repair. Over the last several years, new techniques - particularly in structural biology - have provided molecular mechanisms for Mec1ATR function. It is becoming increasingly clear how post-translational modification of Mec1ATR and its interaction partners modulates the DNA damage checkpoint. In this review, we summarise the most recent work unravelling Mec1ATR function in the DNA damage checkpoint and provide a molecular context for its regulation by phosphorylation.
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Affiliation(s)
- Luke A Yates
- Section of Structural, Department of Infectious Disease, Sir Alexander Fleming Building, Imperial College London, SW7 2AZ, UK; DNA processing machines laboratory, Francis Crick Institute, London NW1 1AT, UK.
| | - Xiaodong Zhang
- Section of Structural, Department of Infectious Disease, Sir Alexander Fleming Building, Imperial College London, SW7 2AZ, UK; DNA processing machines laboratory, Francis Crick Institute, London NW1 1AT, UK.
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13
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Einig E, Jin C, Andrioletti V, Macek B, Popov N. RNAPII-dependent ATM signaling at collisions with replication forks. Nat Commun 2023; 14:5147. [PMID: 37620345 PMCID: PMC10449895 DOI: 10.1038/s41467-023-40924-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 08/16/2023] [Indexed: 08/26/2023] Open
Abstract
Deregulation of RNA Polymerase II (RNAPII) by oncogenic signaling leads to collisions of RNAPII with DNA synthesis machinery (transcription-replication conflicts, TRCs). TRCs can result in DNA damage and are thought to underlie genomic instability in tumor cells. Here we provide evidence that elongating RNAPII nucleates activation of the ATM kinase at TRCs to stimulate DNA repair. We show the ATPase WRNIP1 associates with RNAPII and limits ATM activation during unperturbed cell cycle. WRNIP1 binding to elongating RNAPII requires catalytic activity of the ubiquitin ligase HUWE1. Mutation of HUWE1 induces TRCs, promotes WRNIP1 dissociation from RNAPII and binding to the replisome, stimulating ATM recruitment and activation at RNAPII. TRCs and translocation of WRNIP1 are rapidly induced in response to hydroxyurea treatment to activate ATM and facilitate subsequent DNA repair. We propose that TRCs can provide a controlled mechanism for stalling of replication forks and ATM activation, instrumental in cellular response to replicative stress.
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Affiliation(s)
- Elias Einig
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Mueller-Str 14, 72076, Tübingen, Germany
| | - Chao Jin
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Mueller-Str 14, 72076, Tübingen, Germany
| | - Valentina Andrioletti
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Mueller-Str 14, 72076, Tübingen, Germany
- enGenome S.R.L., Via Fratelli Cuzio 42, 27100, Pavia, Italy
| | - Boris Macek
- Interfaculty Institute of Cell Biology, Eberhard Karls University of Tübingen, Auf d. Morgenstelle 15, 72076, Tübingen, Germany
| | - Nikita Popov
- Department of Medical Oncology and Pulmonology, University Hospital Tübingen, Otfried-Mueller-Str 14, 72076, Tübingen, Germany.
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14
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Kaur P, Nagar S, Mehta R, Sahadeo K, Vancura A. Hydroxyurea and inactivation of checkpoint kinase MEC1 inhibit transcription termination and pre-mRNA cleavage at polyadenylation sites in budding yeast. Sci Rep 2023; 13:13106. [PMID: 37567961 PMCID: PMC10421882 DOI: 10.1038/s41598-023-40294-3] [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: 02/16/2023] [Accepted: 08/08/2023] [Indexed: 08/13/2023] Open
Abstract
The DNA damage response (DDR) is an evolutionarily conserved process essential for cell survival. The transcription changes triggered by DDR depend on the nature of DNA damage, activation of checkpoint kinases, and the stage of cell cycle. The transcription changes can be localized and affect only damaged DNA, but they can be also global and affect genes that are not damaged. While the purpose of localized transcription inhibition is to avoid transcription of damaged genes and make DNA accessible for repair, the purpose and mechanisms of global transcription inhibition of undamaged genes are less well understood. We show here that a brief cell treatment with hydroxyurea (HU) globally inhibits RNA synthesis and transcription by RNA polymerase I, II, and III (RNAPI, RNAPII, and RNAPIII). HU reduces efficiency of transcription termination and inhibits pre-mRNA cleavage at the polyadenylation (pA) sites, destabilizes mRNAs, and shortens poly(A) tails of mRNAs, indicating defects in pre-mRNA 3' end processing. Inactivation of the checkpoint kinase Mec1p downregulates the efficiency of transcription termination and reduces the efficiency of pre-mRNAs clevage at the pA sites, suggesting the involvement of DNA damage checkpoint in transcription termination and pre-mRNA 3' end processing.
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Affiliation(s)
- Pritpal Kaur
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY, 11439, USA
| | - Shreya Nagar
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY, 11439, USA
| | - Riddhi Mehta
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY, 11439, USA
| | - Kyle Sahadeo
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY, 11439, USA
| | - Ales Vancura
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY, 11439, USA.
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15
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Bhowmick R, Mehta KPM, Lerdrup M, Cortez D. Integrator facilitates RNAPII removal to prevent transcription-replication collisions and genome instability. Mol Cell 2023; 83:2357-2366.e8. [PMID: 37295432 PMCID: PMC10330747 DOI: 10.1016/j.molcel.2023.05.015] [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: 02/16/2023] [Revised: 04/17/2023] [Accepted: 05/10/2023] [Indexed: 06/12/2023]
Abstract
DNA replication preferentially initiates close to active transcription start sites (TSSs) in the human genome. Transcription proceeds discontinuously with an accumulation of RNA polymerase II (RNAPII) in a paused state near the TSS. Consequently, replication forks inevitably encounter paused RNAPII soon after replication initiates. Hence, dedicated machinery may be needed to remove RNAPII and facilitate unperturbed fork progression. In this study, we discovered that Integrator, a transcription termination machinery involved in the processing of RNAPII transcripts, interacts with the replicative helicase at active forks and promotes the removal of RNAPII from the path of the replication fork. Integrator-deficient cells have impaired replication fork progression and accumulate hallmarks of genome instability including chromosome breaks and micronuclei. The Integrator complex resolves co-directional transcription-replication conflicts to facilitate faithful DNA replication.
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Affiliation(s)
- Rahul Bhowmick
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA.
| | - Kavi P M Mehta
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Mads Lerdrup
- Center for Chromosome Stability, Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200 Copenhagen, Denmark
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA.
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16
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Miller CLW, Winston F. The conserved histone chaperone Spt6 is strongly required for DNA replication and genome stability. Cell Rep 2023; 42:112264. [PMID: 36924499 PMCID: PMC10106089 DOI: 10.1016/j.celrep.2023.112264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 12/31/2022] [Accepted: 02/27/2023] [Indexed: 03/17/2023] Open
Abstract
Histone chaperones are an important class of proteins that regulate chromatin accessibility for DNA-templated processes. Spt6 is a conserved histone chaperone and key regulator of transcription and chromatin structure. However, its functions outside of these roles have been little explored. In this work, we demonstrate a requirement for S. cerevisiae Spt6 in DNA replication and, more broadly, as a regulator of genome stability. Depletion or mutation of Spt6 impairs DNA replication in vivo. Additionally, spt6 mutants are sensitive to DNA replication stress-inducing agents. Interestingly, this sensitivity is independent of the association of Spt6 with RNA polymerase II (RNAPII), suggesting that spt6 mutants have a transcription-independent impairment of DNA replication. Specifically, genomic studies reveal that spt6 mutants have decreased loading of the MCM replicative helicase at replication origins, suggesting that Spt6 promotes origin licensing. Our results identify Spt6 as a regulator of genome stability, at least in part through a role in DNA replication.
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Affiliation(s)
- Catherine L W Miller
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Fred Winston
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA.
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17
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Weiβ M, Chanou A, Schauer T, Tvardovskiy A, Meiser S, König AC, Schmidt T, Kruse E, Ummethum H, Trauner M, Werner M, Lalonde M, Hauck SM, Scialdone A, Hamperl S. Single-copy locus proteomics of early- and late-firing DNA replication origins identifies a role of Ask1/DASH complex in replication timing control. Cell Rep 2023; 42:112045. [PMID: 36701236 PMCID: PMC9989823 DOI: 10.1016/j.celrep.2023.112045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 11/28/2022] [Accepted: 01/13/2023] [Indexed: 01/27/2023] Open
Abstract
The chromatin environment at origins of replication is thought to influence DNA replication initiation in eukaryotic genomes. However, it remains unclear how and which chromatin features control the firing of early-efficient (EE) or late-inefficient (LI) origins. Here, we use site-specific recombination and single-locus chromatin isolation to purify EE and LI replication origins in Saccharomyces cerevisiae. Using mass spectrometry, we define the protein composition of native chromatin regions surrounding the EE and LI replication start sites. In addition to known origin interactors, we find the microtubule-binding Ask1/DASH complex as an origin-regulating factor. Strikingly, tethering of Ask1 to individual origin sites advances replication timing (RT) of the targeted chromosomal domain. Targeted degradation of Ask1 globally changes RT of a subset of origins, which can be reproduced by inhibiting microtubule dynamics. Thus, our findings mechanistically connect RT and chromosomal organization via Ask1/DASH with the microtubule cytoskeleton.
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Affiliation(s)
- Matthias Weiβ
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Anna Chanou
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Tamas Schauer
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Andrey Tvardovskiy
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Stefan Meiser
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany; Institute of Functional Epigenetics, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Institute of Computational Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Ann-Christine König
- Metabolomics and Proteomics Core, Helmholtz Zentrum München, German Center for Environmental Health, Heidemannstrasse 1, 80939 München, Germany
| | - Tobias Schmidt
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Elisabeth Kruse
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Henning Ummethum
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Manuel Trauner
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Marcel Werner
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Maxime Lalonde
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany
| | - Stefanie M Hauck
- Metabolomics and Proteomics Core, Helmholtz Zentrum München, German Center for Environmental Health, Heidemannstrasse 1, 80939 München, Germany
| | - Antonio Scialdone
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany; Institute of Functional Epigenetics, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Institute of Computational Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Stephan Hamperl
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany.
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18
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Gospodinov A, Dzhokova S, Petrova M, Ugrinova I. Chromatin regulators in DNA replication and genome stability maintenance during S-phase. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 135:243-280. [PMID: 37061334 DOI: 10.1016/bs.apcsb.2023.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
The duplication of genetic information is central to life. The replication of genetic information is strictly controlled to ensure that each piece of genomic DNA is copied only once during a cell cycle. Factors that slow or stop replication forks cause replication stress. Replication stress is a major source of genome instability in cancer cells. Multiple control mechanisms facilitate the unimpeded fork progression, prevent fork collapse and coordinate fork repair. Chromatin alterations, caused by histone post-translational modifications and chromatin remodeling, have critical roles in normal replication and in avoiding replication stress and its consequences. This text reviews the chromatin regulators that ensure DNA replication and the proper response to replication stress. We also briefly touch on exploiting replication stress in therapeutic strategies. As chromatin regulators are frequently mutated in cancer, manipulating their activity could provide many possibilities for personalized treatment.
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Affiliation(s)
- Anastas Gospodinov
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
| | - Stefka Dzhokova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Maria Petrova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Iva Ugrinova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
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19
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Shan CM, Fang Y, Jia S. Leaving histone unturned for epigenetic inheritance. FEBS J 2023; 290:310-320. [PMID: 34726351 PMCID: PMC9058036 DOI: 10.1111/febs.16260] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/09/2021] [Accepted: 11/01/2021] [Indexed: 02/05/2023]
Abstract
Post-translational modifications in histones play important roles in regulating chromatin structure and gene expression programs, and the modified histones can be passed on to subsequent generations as an epigenetic memory. The fission yeast has been a great model organism for studying histone modifications in heterochromatin assembly and epigenetic inheritance. Here, we review findings in this organism that cemented the idea of chromatin-based inheritance and highlight recent studies that reveal the role of histone turnover in regulating this process.
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Affiliation(s)
- Chun-Min Shan
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
- Present address: State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yimeng Fang
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Songtao Jia
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
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20
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The Paf1 complex is required for RNA polymerase II removal in response to DNA damage. Proc Natl Acad Sci U S A 2022; 119:e2207332119. [PMID: 36161924 DOI: 10.1073/pnas.2207332119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Rpb1, the largest subunit of RNA polymerase II (RNAPII), is rapidly polyubiquitinated and degraded in response to DNA damage; this process is considered to be a "mechanism of last resort'' employed by cells. The underlying mechanism of this process remains elusive. Here, we uncovered a previously uncharacterized multistep pathway in which the polymerase-associated factor 1 (Paf1) complex (PAF1C, composed of the subunits Ctr9, Paf1, Leo1, Cdc73, and Rtf1) is involved in regulating the RNAPII pool by stimulating Elongin-Cullin E3 ligase complex-mediated Rpb1 polyubiquitination and subsequent degradation by the proteasome following DNA damage. Mechanistically, Spt5 is dephosphorylated following DNA damage, thereby weakening the interaction between the Rtf1 subunit and Spt5, which might be a key step in initiating Rpb1 degradation. Next, Rad26 is loaded onto stalled RNAPII to replace the Spt4/Spt5 complex in an RNAPII-dependent manner and, in turn, recruits more PAF1C to DNA lesions via the binding of Rad26 to the Leo1 subunit. Importantly, the PAF1C, assembled in a Ctr9-mediated manner, coordinates with Rad26 to localize the Elongin-Cullin complex on stalled RNAPII, thereby inducing RNAPII removal, in which the heterodimer Paf1/Leo1 and the subunit Cdc73 play important roles. Together, our results clearly revealed a new role of the intact PAF1C in regulating the RNAPII pool in response to DNA damage.
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21
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Hsieh LJ, Gourdet MA, Moore CM, Muñoz EN, Gamarra N, Ramani V, Narlikar GJ. A hexasome is the preferred substrate for the INO80 chromatin remodeling complex, allowing versatility of function. Mol Cell 2022; 82:2098-2112.e4. [PMID: 35597239 PMCID: PMC9351570 DOI: 10.1016/j.molcel.2022.04.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 12/10/2021] [Accepted: 04/20/2022] [Indexed: 10/18/2022]
Abstract
The critical role of the INO80 chromatin remodeling complex in transcription is commonly attributed to its nucleosome sliding activity. Here, we have found that INO80 prefers to mobilize hexasomes over nucleosomes. INO80's preference for hexasomes reaches up to ∼60 fold when flanking DNA overhangs approach ∼18-bp linkers in yeast gene bodies. Correspondingly, deletion of INO80 significantly affects the positions of hexasome-sized particles within yeast genes in vivo. Our results raise the possibility that INO80 promotes nucleosome sliding by dislodging an H2A-H2B dimer, thereby making a nucleosome transiently resemble a hexasome. We propose that this mechanism allows INO80 to rapidly mobilize nucleosomes at promoters and hexasomes within gene bodies. Rapid repositioning of hexasomes that are generated in the wake of transcription may mitigate spurious transcription. More generally, such versatility may explain how INO80 regulates chromatin architecture during the diverse processes of transcription, replication, and repair.
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Affiliation(s)
- Laura J Hsieh
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Muryam A Gourdet
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Camille M Moore
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Elise N Muñoz
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Nathan Gamarra
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Vijay Ramani
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Geeta J Narlikar
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
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22
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Bay LTE, Syljuåsen RG, Landsverk HB. A novel, rapid and sensitive flow cytometry method reveals degradation of promoter proximal paused RNAPII in the presence and absence of UV. Nucleic Acids Res 2022; 50:e89. [PMID: 35641102 PMCID: PMC9410883 DOI: 10.1093/nar/gkac434] [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: 12/21/2021] [Revised: 04/08/2022] [Accepted: 05/11/2022] [Indexed: 12/17/2022] Open
Abstract
RNA polymerase II (RNAPII) is emerging as an important factor in DNA damage responses, but how it responds to genotoxic stress is not fully understood. We have developed a rapid and sensitive flow cytometry method to study chromatin binding of RNAPII in individual human cells through the cell cycle. Indicating enhanced transcription initiation at early timepoints, levels of RNAPII were increased at 15–30min after UV-induced DNA damage. This was particularly evident for the S5 phosphorylated form of RNAPII (pRNAPII S5), which is typically associated with promoter proximal pausing. Furthermore, degradation of pRNAPII S5 frequently occurs, as its levels on chromatin were strongly enhanced by the proteasome inhibitor MG132 with and without UV. Remarkably, inhibiting pause release with 5,6-dichloro-1-beta-ribo-furanosyl benzimidazole (DRB) further promoted UV-induced degradation of pRNAPII S5, suggesting enhanced initiation may lead to a phenomenon of ‘promoter proximal crowding’ resulting in premature termination via degradation of RNAPII. Moreover, pRNAPII S2 levels on chromatin were more stable in S phase of the cell cycle 2h after UV, indicating cell cycle specific effects. Altogether our results demonstrate a useful new method and suggest that degradation of promoter proximal RNAPII plays an unanticipated large role both during normal transcription and after UV.
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Affiliation(s)
- Lilli T E Bay
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway
| | - Randi G Syljuåsen
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway
| | - Helga B Landsverk
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway
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23
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Brickner JR, Garzon JL, Cimprich KA. Walking a tightrope: The complex balancing act of R-loops in genome stability. Mol Cell 2022; 82:2267-2297. [PMID: 35508167 DOI: 10.1016/j.molcel.2022.04.014] [Citation(s) in RCA: 81] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/28/2022] [Accepted: 04/10/2022] [Indexed: 12/14/2022]
Abstract
Although transcription is an essential cellular process, it is paradoxically also a well-recognized cause of genomic instability. R-loops, non-B DNA structures formed when nascent RNA hybridizes to DNA to displace the non-template strand as single-stranded DNA (ssDNA), are partially responsible for this instability. Yet, recent work has begun to elucidate regulatory roles for R-loops in maintaining the genome. In this review, we discuss the cellular contexts in which R-loops contribute to genomic instability, particularly during DNA replication and double-strand break (DSB) repair. We also summarize the evidence that R-loops participate as an intermediate during repair and may influence pathway choice to preserve genomic integrity. Finally, we discuss the immunogenic potential of R-loops and highlight their links to disease should they become pathogenic.
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Affiliation(s)
- Joshua R Brickner
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jada L Garzon
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Karlene A Cimprich
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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24
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Chakraborty P, Magnuson T. INO80 requires a polycomb subunit to regulate the establishment of poised chromatin in murine spermatocytes. Development 2022; 149:273926. [PMID: 35006254 PMCID: PMC8881737 DOI: 10.1242/dev.200089] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 11/23/2021] [Indexed: 01/12/2023]
Abstract
INO80 is the catalytic subunit of the INO80-chromatin remodeling complex that is involved in DNA replication, repair and transcription regulation. Ino80 deficiency in murine spermatocytes (Ino80cKO) results in pachytene arrest of spermatocytes due to incomplete synapsis and aberrant DNA double-strand break repair, which leads to apoptosis. RNA-seq on Ino80cKO spermatocytes revealed major changes in transcription, indicating that an aberrant transcription program arises upon INO80 depletion. In Ino80WT spermatocytes, genome-wide analysis showed that INO80-binding sites were mostly promoter proximal and necessary for the regulation of spermatogenic gene expression, primarily of premeiotic and meiotic genes. Furthermore, most of the genes poised for activity, as well as those genes that are active, shared INO80 binding. In Ino80cKO spermatocytes, most poised genes demonstrated de-repression due to reduced H3K27me3 enrichment and, in turn, showed increased expression levels. INO80 interacts with the core PRC2 complex member SUZ12 and promotes its recruitment. Furthermore, INO80 mediates H2A.Z incorporation at the poised promoters, which was reduced in Ino80cKO spermatocytes. Taken together, INO80 is emerging as a major regulator of the meiotic transcription program by mediating poised chromatin establishment through SUZ12 binding.
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Affiliation(s)
- Prabuddha Chakraborty
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7264, USA
| | - Terry Magnuson
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7264, USA,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7264, USA,Author for correspondence ()
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25
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The role of chromatin at transcription-replication conflicts as a genome safeguard. Biochem Soc Trans 2021; 49:2727-2736. [PMID: 34821364 DOI: 10.1042/bst20210691] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/08/2021] [Accepted: 11/10/2021] [Indexed: 11/17/2022]
Abstract
DNA replication ensures the correct copying of the genome and the faithful transfer of the genetic information to the offspring. However, obstacles to replication fork (RF) progression cause RF stalling and compromise efficient genome duplication. Since replication uses the same DNA template as transcription, both transcription and replication must be coordinated to prevent Transcription-Replication Conflicts (TRCs) that could stall RF progression. Several factors contribute to limit the occurrence of such conflicts and their harmful impact on genome integrity. Increasing evidence indicates that chromatin homeostasis plays a key role in the cellular response to TRCs as well as in the preservation of genome integrity. Indeed, chromatin regulating enzymes are frequently mutated in cancer cells, a common characteristic of which is genome instability. Therefore, understanding the role of chromatin in TRC occurrence and resolution may help identify the molecular mechanism by which chromatin protects genome integrity, and the causes and physiological relevance of the high mutation rates of chromatin regulating factors in cancer. Here we review the current knowledge in the field, as well as the perspectives and future applications.
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26
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Zardoni L, Nardini E, Brambati A, Lucca C, Choudhary R, Loperfido F, Sabbioneda S, Liberi G. Elongating RNA polymerase II and RNA:DNA hybrids hinder fork progression and gene expression at sites of head-on replication-transcription collisions. Nucleic Acids Res 2021; 49:12769-12784. [PMID: 34878142 PMCID: PMC8682787 DOI: 10.1093/nar/gkab1146] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 10/26/2021] [Accepted: 11/02/2021] [Indexed: 11/20/2022] Open
Abstract
Uncoordinated clashes between replication forks and transcription cause replication stress and genome instability, which are hallmarks of cancer and neurodegeneration. Here, we investigate the outcomes of head-on replication-transcription collisions, using as a model system budding yeast mutants for the helicase Sen1, the ortholog of human Senataxin. We found that RNA Polymerase II accumulates together with RNA:DNA hybrids at sites of head-on collisions. The replication fork and RNA Polymerase II are both arrested during the clash, leading to DNA damage and, in the long run, the inhibition of gene expression. The inactivation of RNA Polymerase II elongation factors, such as the HMG-like protein Spt2 and the DISF and PAF complexes, but not alterations in chromatin structure, allows replication fork progression through transcribed regions. Attenuation of RNA Polymerase II elongation rescues RNA:DNA hybrid accumulation and DNA damage sensitivity caused by the absence of Sen1, but not of RNase H proteins, suggesting that such enzymes counteract toxic RNA:DNA hybrids at different stages of the cell cycle with Sen1 mainly acting in replication. We suggest that the main obstacle to replication fork progression is the elongating RNA Polymerase II engaged in an R-loop, rather than RNA:DNA hybrids per se or hybrid-associated chromatin modifications.
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Affiliation(s)
- Luca Zardoni
- Istituto di Genetica Molecolare "Luigi Luca Cavalli-Sforza", CNR, 27100 Pavia, Italy.,Scuola Universitaria Superiore IUSS, 27100 Pavia, Italy
| | - Eleonora Nardini
- Istituto di Genetica Molecolare "Luigi Luca Cavalli-Sforza", CNR, 27100 Pavia, Italy
| | - Alessandra Brambati
- Istituto di Genetica Molecolare "Luigi Luca Cavalli-Sforza", CNR, 27100 Pavia, Italy
| | | | | | - Federica Loperfido
- Istituto di Genetica Molecolare "Luigi Luca Cavalli-Sforza", CNR, 27100 Pavia, Italy
| | - Simone Sabbioneda
- Istituto di Genetica Molecolare "Luigi Luca Cavalli-Sforza", CNR, 27100 Pavia, Italy
| | - Giordano Liberi
- Istituto di Genetica Molecolare "Luigi Luca Cavalli-Sforza", CNR, 27100 Pavia, Italy.,IFOM Foundation, 20139 Milan, Italy
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27
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Chen F, Liu B, Zeng J, Guo L, Ge X, Feng W, Li DF, Zhou H, Long J. Crystal Structure of the Core Module of the Yeast Paf1 Complex. J Mol Biol 2021; 434:167369. [PMID: 34852272 DOI: 10.1016/j.jmb.2021.167369] [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: 10/07/2021] [Revised: 11/08/2021] [Accepted: 11/12/2021] [Indexed: 12/31/2022]
Abstract
The highly conserved multifunctional polymerase-associated factor 1 (Paf1) complex (PAF1C), which consists of five core subunits: Ctr9, Paf1, Leo1, Cdc73, and Rtf1, acts as a diverse hub that regulates all stages of RNA polymerase II-mediated transcription and various other cellular functions. However, the underlying mechanisms remain unclear. Here, we report the crystal structure of the core module derived from a quaternary Ctr9/Paf1/Cdc73/Rtf1 complex of S. cerevisiae PAF1C, which reveals interfaces between the tetratricopeptide repeat module in Ctr9 and Cdc73 or Rtf1, and find that the Ctr9/Paf1 subcomplex is the key scaffold for PAF1C assembly. Our study demonstrates that Cdc73 binds Ctr9/Paf1 subcomplex with a very similar conformation within thermophilic fungi or human PAF1C, and that the binding of Cdc73 to PAF1C is important for yeast growth. Importantly, our structure reveals for the first time that the extreme C-terminus of Rtf1 adopts an "L"-shaped structure, which interacts with Ctr9 specifically. In addition, disruption of the binding of either Cdc73 or Rtf1 to PAF1C greatly affects the normal level of histone H2B K123 monoubiquitination in vivo. Collectively, our results provide a structural insight into the architecture of the quaternary Ctr9/Paf1/Cdc73/Rtf1 complex and PAF1C functional regulation.
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Affiliation(s)
- Feilong Chen
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, and College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Beibei Liu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, and College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Jianwei Zeng
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lu Guo
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xuan Ge
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Feng
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - De-Feng Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Hao Zhou
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, and College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China.
| | - Jiafu Long
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, and College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China; Nankai International Advanced Research Institute (Shenzhen Futian), Shenzhen, Guangdong 518045, China.
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28
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Papadopoulos D, Solvie D, Baluapuri A, Endres T, Ha SA, Herold S, Kalb J, Giansanti C, Schülein-Völk C, Ade CP, Schneider C, Gaballa A, Vos S, Fischer U, Dobbelstein M, Wolf E, Eilers M. MYCN recruits the nuclear exosome complex to RNA polymerase II to prevent transcription-replication conflicts. Mol Cell 2021; 82:159-176.e12. [PMID: 34847357 DOI: 10.1016/j.molcel.2021.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 08/17/2021] [Accepted: 11/02/2021] [Indexed: 01/05/2023]
Abstract
The MYCN oncoprotein drives the development of numerous neuroendocrine and pediatric tumors. Here we show that MYCN interacts with the nuclear RNA exosome, a 3'-5' exoribonuclease complex, and recruits the exosome to its target genes. In the absence of the exosome, MYCN-directed elongation by RNA polymerase II (RNAPII) is slow and non-productive on a large group of cell-cycle-regulated genes. During the S phase of MYCN-driven tumor cells, the exosome is required to prevent the accumulation of stalled replication forks and of double-strand breaks close to the transcription start sites. Upon depletion of the exosome, activation of ATM causes recruitment of BRCA1, which stabilizes nuclear mRNA decapping complexes, leading to MYCN-dependent transcription termination. Disruption of mRNA decapping in turn activates ATR, indicating transcription-replication conflicts. We propose that exosome recruitment by MYCN maintains productive transcription elongation during S phase and prevents transcription-replication conflicts to maintain the rapid proliferation of neuroendocrine tumor cells.
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Affiliation(s)
- Dimitrios Papadopoulos
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Daniel Solvie
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Apoorva Baluapuri
- Cancer Systems Biology Group, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Theresa Endres
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Stefanie Anh Ha
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Steffi Herold
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Jacqueline Kalb
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Celeste Giansanti
- Institute of Molecular Oncology, Center of Molecular Biosciences, University of Göttingen, Justus von Liebig Weg 11, 37077 Göttingen, Germany
| | - Christina Schülein-Völk
- Core Unit High-Content Microscopy, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Carsten Patrick Ade
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Cornelius Schneider
- Department of Biochemistry, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Abdallah Gaballa
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Seychelle Vos
- Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02142, USA
| | - Utz Fischer
- Department of Biochemistry, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Matthias Dobbelstein
- Institute of Molecular Oncology, Center of Molecular Biosciences, University of Göttingen, Justus von Liebig Weg 11, 37077 Göttingen, Germany
| | - Elmar Wolf
- Cancer Systems Biology Group, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Martin Eilers
- Theodor Boveri Institute, Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
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29
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Hurst V, Challa K, Jonas F, Forey R, Sack R, Seebacher J, Schmid CD, Barkai N, Shimada K, Gasser SM, Poli J. A regulatory phosphorylation site on Mec1 controls chromatin occupancy of RNA polymerases during replication stress. EMBO J 2021; 40:e108439. [PMID: 34569643 PMCID: PMC8561635 DOI: 10.15252/embj.2021108439] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 09/08/2021] [Accepted: 09/10/2021] [Indexed: 01/16/2023] Open
Abstract
Upon replication stress, budding yeast checkpoint kinase Mec1ATR triggers the downregulation of transcription, thereby reducing the level of RNA polymerase (RNAP) on chromatin to facilitate replication fork progression. Here, we identify a hydroxyurea-induced phosphorylation site on Mec1, Mec1-S1991, that contributes to the eviction of RNAPII and RNAPIII during replication stress. The expression of the non-phosphorylatable mec1-S1991A mutant reduces replication fork progression genome-wide and compromises survival on hydroxyurea. This defect can be suppressed by destabilizing chromatin-bound RNAPII through a TAP fusion to its Rpb3 subunit, suggesting that lethality in mec1-S1991A mutants arises from replication-transcription conflicts. Coincident with a failure to repress gene expression on hydroxyurea in mec1-S1991A cells, highly transcribed genes such as GAL1 remain bound at nuclear pores. Consistently, we find that nuclear pore proteins and factors controlling RNAPII and RNAPIII are phosphorylated in a Mec1-dependent manner on hydroxyurea. Moreover, we show that Mec1 kinase also contributes to reduced RNAPII occupancy on chromatin during an unperturbed S phase by promoting degradation of the Rpb1 subunit.
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Affiliation(s)
- Verena Hurst
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Faculty of Natural Sciences, University of Basel, Basel, Switzerland
| | - Kiran Challa
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Felix Jonas
- Departments of Molecular Genetics and Physics of Complex Systems, Weizmann Institute of Science, Rehovot, Israel
| | - Romain Forey
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier, France
| | - Ragna Sack
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Jan Seebacher
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Christoph D Schmid
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Naama Barkai
- Departments of Molecular Genetics and Physics of Complex Systems, Weizmann Institute of Science, Rehovot, Israel
| | - Kenji Shimada
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Susan M Gasser
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Faculty of Natural Sciences, University of Basel, Basel, Switzerland
| | - Jérôme Poli
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier, France
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30
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Kemiha S, Poli J, Lin YL, Lengronne A, Pasero P. Toxic R-loops: Cause or consequence of replication stress? DNA Repair (Amst) 2021; 107:103199. [PMID: 34399314 DOI: 10.1016/j.dnarep.2021.103199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/28/2021] [Accepted: 07/30/2021] [Indexed: 01/08/2023]
Abstract
Transcription-replication conflicts (TRCs) represent a potential source of endogenous replication stress (RS) and genomic instability in eukaryotic cells but the mechanisms that underlie this instability remain poorly understood. Part of the problem could come from non-B DNA structures called R-loops, which are formed of a RNA:DNA hybrid and a displaced ssDNA loop. In this review, we discuss different scenarios in which R-loops directly or indirectly interfere with DNA replication. We also present other types of TRCs that may not depend on R-loops to impede fork progression. Finally, we discuss alternative models in which toxic RNA:DNA hybrids form at stalled forks as a consequence - but not a cause - of replication stress and interfere with replication resumption.
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Affiliation(s)
- Samira Kemiha
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier, France
| | - Jérôme Poli
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier, France
| | - Yea-Lih Lin
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier, France
| | - Armelle Lengronne
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier, France
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier, France.
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31
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Gao J, Zhang P, Li X, Wu W, Wei H, Zhang W. Toward an understanding of the detection and function of R-loops in plants. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:6110-6122. [PMID: 34115858 DOI: 10.1093/jxb/erab280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 06/10/2021] [Indexed: 06/12/2023]
Abstract
Although lagging behind studies in humans and other mammals, studies of R-loops in plants have recently entered an exciting stage in which the roles of R-loops in gene expression, genome stability, epigenomic signatures, and plant development and stress responses are being elucidated. Here, we review the strengths and weaknesses of existing methodologies, which were largely developed for R-loop studies in mammals, and then discuss the potential challenges of applying these methodologies to R-loop studies in plants. We then focus on recent advances in the functional characterization of R-loops in Arabidopsis thaliana and rice. Recent studies in plants indicate that there are coordinated relationships between R-loops and gene expression, and between R-loops and epigenomic signatures that depend, in part, on the types of R-loops involved. Finally, we discuss the emerging roles of R-loops in plants and directions for future research.
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Affiliation(s)
- Jingjing Gao
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Pengyue Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Xinxu Li
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Wenqi Wu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China
| | - Hairong Wei
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
| | - Wenli Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
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32
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Bhagwat M, Nagar S, Kaur P, Mehta R, Vancurova I, Vancura A. Replication stress inhibits synthesis of histone mRNAs in yeast by removing Spt10p and Spt21p from the histone promoters. J Biol Chem 2021; 297:101246. [PMID: 34582893 PMCID: PMC8551654 DOI: 10.1016/j.jbc.2021.101246] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/17/2021] [Accepted: 09/23/2021] [Indexed: 12/27/2022] Open
Abstract
Proliferating cells coordinate histone and DNA synthesis to maintain correct stoichiometry for chromatin assembly. Histone mRNA levels must be repressed when DNA replication is inhibited to prevent toxicity and genome instability due to free non-chromatinized histone proteins. In mammalian cells, replication stress triggers degradation of histone mRNAs, but it is unclear if this mechanism is conserved from other species. The aim of this study was to identify the histone mRNA decay pathway in the yeast Saccharomyces cerevisiae and determine the mechanism by which DNA replication stress represses histone mRNAs. Using reverse transcription-quantitative PCR and chromatin immunoprecipitation–quantitative PCR, we show here that histone mRNAs can be degraded by both 5′ → 3′ and 3′ → 5′ pathways; however, replication stress does not trigger decay of histone mRNA in yeast. Rather, replication stress inhibits transcription of histone genes by removing the histone gene–specific transcription factors Spt10p and Spt21p from histone promoters, leading to disassembly of the preinitiation complexes and eviction of RNA Pol II from histone genes by a mechanism facilitated by checkpoint kinase Rad53p and histone chaperone Asf1p. In contrast, replication stress does not remove SCB-binding factor transcription complex, another activator of histone genes, from the histone promoters, suggesting that Spt10p and Spt21p have unique roles in the transcriptional downregulation of histone genes during replication stress. Together, our data show that, unlike in mammalian cells, replication stress in yeast does not trigger decay of histone mRNAs but inhibits histone transcription.
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Affiliation(s)
- Madhura Bhagwat
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Shreya Nagar
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Pritpal Kaur
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Riddhi Mehta
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Ivana Vancurova
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Ales Vancura
- Department of Biological Sciences, St John's University, Queens, New York, USA.
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33
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Lloyd R, Urban V, Muñoz-Martínez F, Ayestaran I, Thomas J, de Renty C, O’Connor M, Forment J, Galanty Y, Jackson S. Loss of Cyclin C or CDK8 provides ATR inhibitor resistance by suppressing transcription-associated replication stress. Nucleic Acids Res 2021; 49:8665-8683. [PMID: 34329458 PMCID: PMC8421211 DOI: 10.1093/nar/gkab628] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 07/04/2021] [Accepted: 07/09/2021] [Indexed: 02/07/2023] Open
Abstract
The protein kinase ATR plays pivotal roles in DNA repair, cell cycle checkpoint engagement and DNA replication. Consequently, ATR inhibitors (ATRi) are in clinical development for the treatment of cancers, including tumours harbouring mutations in the related kinase ATM. However, it still remains unclear which functions and pathways dominate long-term ATRi efficacy, and how these vary between clinically relevant genetic backgrounds. Elucidating common and genetic-background specific mechanisms of ATRi efficacy could therefore assist in patient stratification and pre-empting drug resistance. Here, we use CRISPR-Cas9 genome-wide screening in ATM-deficient and proficient mouse embryonic stem cells to interrogate cell fitness following treatment with the ATRi, ceralasertib. We identify factors that enhance or suppress ATRi efficacy, with a subset of these requiring intact ATM signalling. Strikingly, two of the strongest resistance-gene hits in both ATM-proficient and ATM-deficient cells encode Cyclin C and CDK8: members of the CDK8 kinase module for the RNA polymerase II mediator complex. We show that Cyclin C/CDK8 loss reduces S-phase DNA:RNA hybrid formation, transcription-replication stress, and ultimately micronuclei formation induced by ATRi. Overall, our work identifies novel biomarkers of ATRi efficacy in ATM-proficient and ATM-deficient cells, and highlights transcription-associated replication stress as a predominant driver of ATRi-induced cell death.
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Affiliation(s)
- Rebecca L Lloyd
- Wellcome/Cancer Research UK Gurdon Institute, and Department of Biochemistry, University of Cambridge, UK
| | - Vaclav Urban
- Bioscience, Oncology R&D, AstraZeneca, Cambridge, UK
| | - Francisco Muñoz-Martínez
- Wellcome/Cancer Research UK Gurdon Institute, and Department of Biochemistry, University of Cambridge, UK
| | - Iñigo Ayestaran
- Wellcome/Cancer Research UK Gurdon Institute, and Department of Biochemistry, University of Cambridge, UK
| | - John C Thomas
- Wellcome/Cancer Research UK Gurdon Institute, and Department of Biochemistry, University of Cambridge, UK
| | | | | | | | - Yaron Galanty
- Wellcome/Cancer Research UK Gurdon Institute, and Department of Biochemistry, University of Cambridge, UK
| | - Stephen P Jackson
- Wellcome/Cancer Research UK Gurdon Institute, and Department of Biochemistry, University of Cambridge, UK
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34
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St Germain C, Zhao H, Barlow JH. Transcription-Replication Collisions-A Series of Unfortunate Events. Biomolecules 2021; 11:1249. [PMID: 34439915 PMCID: PMC8391903 DOI: 10.3390/biom11081249] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/12/2021] [Accepted: 08/17/2021] [Indexed: 02/07/2023] Open
Abstract
Transcription-replication interactions occur when DNA replication encounters genomic regions undergoing transcription. Both replication and transcription are essential for life and use the same DNA template making conflicts unavoidable. R-loops, DNA supercoiling, DNA secondary structure, and chromatin-binding proteins are all potential obstacles for processive replication or transcription and pose an even more potent threat to genome integrity when these processes co-occur. It is critical to maintaining high fidelity and processivity of transcription and replication while navigating through a complex chromatin environment, highlighting the importance of defining cellular pathways regulating transcription-replication interaction formation, evasion, and resolution. Here we discuss how transcription influences replication fork stability, and the safeguards that have evolved to navigate transcription-replication interactions and maintain genome integrity in mammalian cells.
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Affiliation(s)
- Commodore St Germain
- School of Mathematics and Science, Solano Community College, 4000 Suisun Valley Road, Fairfield, CA 94534, USA
- Department of Microbiology and Molecular Genetics, University of California Davis, One Shields Avenue, Davis, CA 95616, USA;
| | - Hongchang Zhao
- Department of Microbiology and Molecular Genetics, University of California Davis, One Shields Avenue, Davis, CA 95616, USA;
| | - Jacqueline H. Barlow
- Department of Microbiology and Molecular Genetics, University of California Davis, One Shields Avenue, Davis, CA 95616, USA;
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35
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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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36
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Francette AM, Tripplehorn SA, Arndt KM. The Paf1 Complex: A Keystone of Nuclear Regulation Operating at the Interface of Transcription and Chromatin. J Mol Biol 2021; 433:166979. [PMID: 33811920 PMCID: PMC8184591 DOI: 10.1016/j.jmb.2021.166979] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/21/2021] [Accepted: 03/24/2021] [Indexed: 12/14/2022]
Abstract
The regulation of transcription by RNA polymerase II is closely intertwined with the regulation of chromatin structure. A host of proteins required for the disassembly, reassembly, and modification of nucleosomes interacts with Pol II to aid its movement and counteract its disruptive effects on chromatin. The highly conserved Polymerase Associated Factor 1 Complex, Paf1C, travels with Pol II and exerts control over transcription elongation and chromatin structure, while broadly impacting the transcriptome in both single cell and multicellular eukaryotes. Recent studies have yielded exciting new insights into the mechanisms by which Paf1C regulates transcription elongation, epigenetic modifications, and post-transcriptional steps in eukaryotic gene expression. Importantly, these functional studies are now supported by an extensive foundation of high-resolution structural information, providing intimate views of Paf1C and its integration into the larger Pol II elongation complex. As a global regulatory factor operating at the interface between chromatin and transcription, the impact of Paf1C is broad and its influence reverberates into other domains of nuclear regulation, including genome stability, telomere maintenance, and DNA replication.
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Affiliation(s)
- Alex M Francette
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Sarah A Tripplehorn
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Karen M Arndt
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States.
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Apte MS, Masuda H, Wheeler DL, Cooper JP. RNAi and Ino80 complex control rate limiting translocation step that moves rDNA to eroding telomeres. Nucleic Acids Res 2021; 49:8161-8176. [PMID: 34244792 PMCID: PMC8373062 DOI: 10.1093/nar/gkab586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 06/18/2021] [Accepted: 07/01/2021] [Indexed: 01/21/2023] Open
Abstract
The discovery of HAATIrDNA, a telomerase-negative survival mode in which canonical telomeres are replaced with ribosomal DNA (rDNA) repeats that acquire chromosome end-protection capability, raised crucial questions as to how rDNA tracts 'jump' to eroding chromosome ends. Here, we show that HAATIrDNA formation is initiated and limited by a single translocation that juxtaposes rDNA from Chromosome (Chr) III onto subtelomeric elements (STE) on Chr I or II; this rare reaction requires RNAi and the Ino80 nucleosome remodeling complex (Ino80C), thus defining an unforeseen relationship between these two machineries. The unique STE-rDNA junction created by this initial translocation is efficiently copied to the remaining STE chromosome ends, independently of RNAi or Ino80C. Intriguingly, both RNAi and Ino80C machineries contain a component that plays dual roles in HAATI subtype choice. Dcr1 of the RNAi pathway and Iec1 of Ino80C both promote HAATIrDNA formation as part of their respective canonical machineries, but both also inhibit formation of the exceedingly rare HAATISTE (where STE sequences mobilize throughout the genome and assume chromosome end protection capacity) in non-canonical, pathway-independent manners. This work provides a glimpse into a previously unrecognized crosstalk between RNAi and Ino80C in controlling unusual translocation reactions that establish telomere-free linear chromosome ends.
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Affiliation(s)
- Manasi S Apte
- Laboratory of Biochemistry and Molecular Biology, NCI, NIH, Bethesda, MD 20892, USA
| | - Hirohisa Masuda
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - David Lee Wheeler
- Laboratory of Biochemistry and Molecular Biology, NCI, NIH, Bethesda, MD 20892, USA
| | - Julia Promisel Cooper
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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The SWI/SNF chromatin remodeling complex helps resolve R-loop-mediated transcription-replication conflicts. Nat Genet 2021; 53:1050-1063. [PMID: 33986538 DOI: 10.1038/s41588-021-00867-2] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 04/06/2021] [Indexed: 02/03/2023]
Abstract
ATP-dependent chromatin remodelers are commonly mutated in human cancer. Mammalian SWI/SNF complexes comprise three conserved multisubunit chromatin remodelers (cBAF, ncBAF and PBAF) that share the BRG1 (also known as SMARCA4) subunit responsible for the main ATPase activity. BRG1 is the most frequently mutated Snf2-like ATPase in cancer. In the present study, we have investigated the role of SWI/SNF in genome instability, a hallmark of cancer cells, given its role in transcription, DNA replication and DNA-damage repair. We show that depletion of BRG1 increases R-loops and R-loop-dependent DNA breaks, as well as transcription-replication (T-R) conflicts. BRG1 colocalizes with R-loops and replication fork blocks, as determined by FANCD2 foci, with BRG1 depletion being epistatic to FANCD2 silencing. Our study, extended to other components of SWI/SNF, uncovers a key role of the SWI/SNF complex, in particular cBAF, in helping resolve R-loop-mediated T-R conflicts, thus, unveiling a new mechanism by which chromatin remodeling protects genome integrity.
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39
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Lalonde M, Trauner M, Werner M, Hamperl S. Consequences and Resolution of Transcription-Replication Conflicts. Life (Basel) 2021; 11:life11070637. [PMID: 34209204 PMCID: PMC8303131 DOI: 10.3390/life11070637] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/28/2021] [Accepted: 06/28/2021] [Indexed: 11/17/2022] Open
Abstract
Transcription–replication conflicts occur when the two critical cellular machineries responsible for gene expression and genome duplication collide with each other on the same genomic location. Although both prokaryotic and eukaryotic cells have evolved multiple mechanisms to coordinate these processes on individual chromosomes, it is now clear that conflicts can arise due to aberrant transcription regulation and premature proliferation, leading to DNA replication stress and genomic instability. As both are considered hallmarks of aging and human diseases such as cancer, understanding the cellular consequences of conflicts is of paramount importance. In this article, we summarize our current knowledge on where and when collisions occur and how these encounters affect the genome and chromatin landscape of cells. Finally, we conclude with the different cellular pathways and multiple mechanisms that cells have put in place at conflict sites to ensure the resolution of conflicts and accurate genome duplication.
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40
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INO80C Remodeler Maintains Genomic Stability by Preventing Promiscuous Transcription at Replication Origins. Cell Rep 2021; 32:108106. [PMID: 32905765 PMCID: PMC7540730 DOI: 10.1016/j.celrep.2020.108106] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 06/26/2020] [Accepted: 08/12/2020] [Indexed: 02/07/2023] Open
Abstract
The proper coordination of transcription with DNA replication and repair is central for genomic stability. We investigate how the INO80C chromatin remodeling enzyme might coordinate these genomic processes. We find that INO80C co-localizes with the origin recognition complex (ORC) at yeast replication origins and is bound to replication initiation sites in mouse embryonic stem cells (mESCs). In yeast· INO80C recruitment requires origin sequences but does not require ORC· suggesting that recruitment is independent of pre-replication complex assembly. In both yeast and ESCs· INO80C co-localizes at origins with Mot1 and NC2 transcription factors· and genetic studies suggest that they function together to promote genome stability. Interestingly· nascent transcript sequencing demonstrates that INO80C and Mot1 prevent pervasive transcription through origin sequences· and absence of these factors leads to formation of new DNA double-strand breaks. We propose that INO80C and Mot1/NC2 function through distinct pathways to limit origin transcription· maintaining genomic stability. The INO80C chromatin remodeler is known to regulate transcription and genomic stability. Topal et al. find that INO80C functions with Mot1 repressor to prevent pervasive transcription at replication origins in yeast and mESCs. Increased ncRNAs lead to new DNA double-strand breaks at origins, linking transcriptional regulation to genomic stability.
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41
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Murashko MM, Stasevich EM, Schwartz AM, Kuprash DV, Uvarova AN, Demin DE. The Role of RNA in DNA Breaks, Repair and Chromosomal Rearrangements. Biomolecules 2021; 11:biom11040550. [PMID: 33918762 PMCID: PMC8069526 DOI: 10.3390/biom11040550] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/31/2021] [Accepted: 04/07/2021] [Indexed: 12/28/2022] Open
Abstract
Incorrect reparation of DNA double-strand breaks (DSB) leading to chromosomal rearrangements is one of oncogenesis's primary causes. Recently published data elucidate the key role of various types of RNA in DSB formation, recognition and repair. With growing interest in RNA biology, increasing RNAs are classified as crucial at the different stages of the main pathways of DSB repair in eukaryotic cells: nonhomologous end joining (NHEJ) and homology-directed repair (HDR). Gene mutations or variation in expression levels of such RNAs can lead to local DNA repair defects, increasing the chromosome aberration frequency. Moreover, it was demonstrated that some RNAs could stimulate long-range chromosomal rearrangements. In this review, we discuss recent evidence demonstrating the role of various RNAs in DSB formation and repair. We also consider how RNA may mediate certain chromosomal rearrangements in a sequence-specific manner.
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Affiliation(s)
- Matvey Mikhailovich Murashko
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Ekaterina Mikhailovna Stasevich
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Anton Markovich Schwartz
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
- Moscow Institute of Physics and Technology, Department of Molecular and Biological Physics, 141701 Moscow, Russia
| | - Dmitriy Vladimirovich Kuprash
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Aksinya Nicolaevna Uvarova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Denis Eriksonovich Demin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
- Correspondence:
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42
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Bar-Ziv R, Brodsky S, Chapal M, Barkai N. Transcription Factor Binding to Replicated DNA. Cell Rep 2021; 30:3989-3995.e4. [PMID: 32209462 DOI: 10.1016/j.celrep.2020.02.114] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 01/13/2020] [Accepted: 02/27/2020] [Indexed: 11/17/2022] Open
Abstract
Genome replication perturbs the DNA regulatory environment by displacing DNA-bound proteins, replacing nucleosomes, and introducing dosage imbalance between regions replicating at different S-phase stages. Recently, we showed that these effects are integrated to maintain transcription homeostasis: replicated genes increase in dosage, but their expression remains stable due to replication-dependent epigenetic changes that suppress transcription. Here, we examine whether reduced transcription from replicated DNA results from limited accessibility to regulatory factors by measuring the time-resolved binding of RNA polymerase II (Pol II) and specific transcription factors (TFs) to DNA during S phase in budding yeast. We show that the Pol II binding pattern is largely insensitive to DNA dosage, indicating limited binding to replicated DNA. In contrast, binding of three TFs (Reb1, Abf1, and Rap1) to DNA increases with the increasing DNA dosage. We conclude that the replication-specific chromatin environment remains accessible to regulatory factors but suppresses RNA polymerase recruitment.
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Affiliation(s)
- Raz Bar-Ziv
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; The Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA 94720, USA
| | - Sagie Brodsky
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Michal Chapal
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Naama Barkai
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
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43
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Challa K, Schmid CD, Kitagawa S, Cheblal A, Iesmantavicius V, Seeber A, Amitai A, Seebacher J, Hauer MH, Shimada K, Gasser SM. Damage-induced chromatome dynamics link Ubiquitin ligase and proteasome recruitment to histone loss and efficient DNA repair. Mol Cell 2021; 81:811-829.e6. [PMID: 33529595 DOI: 10.1016/j.molcel.2020.12.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/13/2020] [Accepted: 12/09/2020] [Indexed: 10/22/2022]
Abstract
Eukaryotic cells package their genomes around histone octamers. In response to DNA damage, checkpoint activation in yeast induces core histone degradation resulting in 20%-40% reduction in nucleosome occupancy. To gain insight into this process, we developed a new approach to analyze the chromatin-associated proteome comprehensively before and after damage. This revealed extensive changes in protein composition after Zeocin-induced damage. First, core histones and the H1 homolog Hho1 were partially lost from chromatin along with replication, transcription, and chromatin remodeling machineries, while ubiquitin ligases and the proteasome were recruited. We found that the checkpoint- and INO80C-dependent recruitment of five ubiquitin-conjugating factors (Rad6, Bre1, Pep5, Ufd4, and Rsp5) contributes to core and linker histone depletion, reducing chromatin compaction and enhancing DNA locus mobility. Importantly, loss of Rad6/Bre1, Ufd4/TRIP12, and Pep5/VPS11 compromise DNA strand invasion kinetics during homology-driven repair. Thus we provide a comprehensive overview of a functionally relevant genome-wide chromatin response to DNA damage.
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Affiliation(s)
- Kiran Challa
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Christoph D Schmid
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Saho Kitagawa
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland; Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Aramaki Aza Aoba 468-1, Aoba-ku, Sendai, 981-8545, Japan
| | - Anaïs Cheblal
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland; Faculty of Natural Sciences, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland
| | - Vytautas Iesmantavicius
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Andrew Seeber
- Center for Advanced Imaging, Northwest Building, 52 Oxford St., Harvard University, Cambridge, MA 02138, USA
| | - Assaf Amitai
- Department of Chemical Engineering, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; The Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
| | - Jan Seebacher
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Michael H Hauer
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Kenji Shimada
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Susan M Gasser
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland; Faculty of Natural Sciences, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.
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44
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Ubiquitylation of MYC couples transcription elongation with double-strand break repair at active promoters. Mol Cell 2021; 81:830-844.e13. [PMID: 33453168 DOI: 10.1016/j.molcel.2020.12.035] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 10/14/2020] [Accepted: 12/16/2020] [Indexed: 12/13/2022]
Abstract
The MYC oncoprotein globally affects the function of RNA polymerase II (RNAPII). The ability of MYC to promote transcription elongation depends on its ubiquitylation. Here, we show that MYC and PAF1c (polymerase II-associated factor 1 complex) interact directly and mutually enhance each other's association with active promoters. PAF1c is rapidly transferred from MYC onto RNAPII. This transfer is driven by the HUWE1 ubiquitin ligase and is required for MYC-dependent transcription elongation. MYC and HUWE1 promote histone H2B ubiquitylation, which alters chromatin structure both for transcription elongation and double-strand break repair. Consistently, MYC suppresses double-strand break accumulation in active genes in a strictly PAF1c-dependent manner. Depletion of PAF1c causes transcription-dependent accumulation of double-strand breaks, despite widespread repair-associated DNA synthesis. Our data show that the transfer of PAF1c from MYC onto RNAPII efficiently couples transcription elongation with double-strand break repair to maintain the genomic integrity of MYC-driven tumor cells.
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45
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Rinaldi C, Pizzul P, Longhese MP, Bonetti D. Sensing R-Loop-Associated DNA Damage to Safeguard Genome Stability. Front Cell Dev Biol 2021; 8:618157. [PMID: 33505970 PMCID: PMC7829580 DOI: 10.3389/fcell.2020.618157] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/02/2020] [Indexed: 12/14/2022] Open
Abstract
DNA transcription and replication are two essential physiological processes that can turn into a threat for genome integrity when they compete for the same DNA substrate. During transcription, the nascent RNA strongly binds the template DNA strand, leading to the formation of a peculiar RNA-DNA hybrid structure that displaces the non-template single-stranded DNA. This three-stranded nucleic acid transition is called R-loop. Although a programed formation of R-loops plays important physiological functions, these structures can turn into sources of DNA damage and genome instability when their homeostasis is altered. Indeed, both R-loop level and distribution in the genome are tightly controlled, and the list of factors involved in these regulatory mechanisms is continuously growing. Over the last years, our knowledge of R-loop homeostasis regulation (formation, stabilization, and resolution) has definitely increased. However, how R-loops affect genome stability and how the cellular response to their unscheduled formation is orchestrated are still not fully understood. In this review, we will report and discuss recent findings about these questions and we will focus on the role of ATM- and Rad3-related (ATR) and Ataxia-telangiectasia-mutated (ATM) kinases in the activation of an R-loop-dependent DNA damage response.
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Affiliation(s)
- Carlo Rinaldi
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
| | - Paolo Pizzul
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
| | - Maria Pia Longhese
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
| | - Diego Bonetti
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
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46
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Noe Gonzalez M, Blears D, Svejstrup JQ. Causes and consequences of RNA polymerase II stalling during transcript elongation. Nat Rev Mol Cell Biol 2021; 22:3-21. [PMID: 33208928 DOI: 10.1038/s41580-020-00308-8] [Citation(s) in RCA: 104] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2020] [Indexed: 02/07/2023]
Abstract
The journey of RNA polymerase II (Pol II) as it transcribes a gene is anything but a smooth ride. Transcript elongation is discontinuous and can be perturbed by intrinsic regulatory barriers, such as promoter-proximal pausing, nucleosomes, RNA secondary structures and the underlying DNA sequence. More substantial blocking of Pol II translocation can be caused by other physiological circumstances and extrinsic obstacles, including other transcribing polymerases, the replication machinery and several types of DNA damage, such as bulky lesions and DNA double-strand breaks. Although numerous different obstacles cause Pol II stalling or arrest, the cell somehow distinguishes between them and invokes different mechanisms to resolve each roadblock. Resolution of Pol II blocking can be as straightforward as temporary backtracking and transcription elongation factor S-II (TFIIS)-dependent RNA cleavage, or as drastic as premature transcription termination or degradation of polyubiquitylated Pol II and its associated nascent RNA. In this Review, we discuss the current knowledge of how these different Pol II stalling contexts are distinguished by the cell, how they overlap with each other, how they are resolved and how, when unresolved, they can cause genome instability.
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Affiliation(s)
- Melvin Noe Gonzalez
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London, UK
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Daniel Blears
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London, UK
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Q Svejstrup
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London, UK.
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.
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47
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Mazina MY, Vorobyeva NE. Chromatin Modifiers in Transcriptional Regulation: New Findings and Prospects. Acta Naturae 2021; 13:16-30. [PMID: 33959384 PMCID: PMC8084290 DOI: 10.32607/actanaturae.11101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 12/17/2020] [Indexed: 02/04/2023] Open
Abstract
Histone-modifying and remodeling complexes are considered the main coregulators that affect transcription by changing the chromatin structure. Coordinated action by these complexes is essential for the transcriptional activation of any eukaryotic gene. In this review, we discuss current trends in the study of histone modifiers and chromatin remodelers, including the functional impact of transcriptional proteins/ complexes i.e., "pioneers"; remodeling and modification of non-histone proteins by transcriptional complexes; the supplementary functions of the non-catalytic subunits of remodelers, and the participation of histone modifiers in the "pause" of RNA polymerase II. The review also includes a scheme illustrating the mechanisms of recruitment of the main classes of remodelers and chromatin modifiers to various sites in the genome and their functional activities.
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Affiliation(s)
- M. Yu. Mazina
- Institute of Gene Biology RAS, Group of transcriptional complexes dynamics, Moscow, 119334 Russia
| | - N. E. Vorobyeva
- Institute of Gene Biology RAS, Group of transcriptional complexes dynamics, Moscow, 119334 Russia
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48
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Liu Y, Lin YL, Pasero P, Chen CL. Topoisomerase I prevents transcription-replication conflicts at transcription termination sites. Mol Cell Oncol 2020; 8:1843951. [PMID: 33553603 PMCID: PMC7849740 DOI: 10.1080/23723556.2020.1843951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
R-loops have both positive and negative impacts on chromosome functions. To identify toxic R-loops, we mapped RNA:DNA hybrids, markers of replication fork stalling and DNA double-strand breaks along the human genome. This analysis indicates that transient replication fork pausing occurs at the transcription termination sites of highly expressed genes enriched in R-loops and prevents head-on conflicts with transcription, in a topoisomerase I-dependent manner.
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Affiliation(s)
- Yaqun Liu
- Institut Curie, PSL Research University, CNRS, UMR3244, Sorbonne Université, Paris, France
| | - Yea-Lih Lin
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Montpellier, France
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Montpellier, France
| | - Chun-Long Chen
- Institut Curie, PSL Research University, CNRS, UMR3244, Sorbonne Université, Paris, France
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49
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WDR82/PNUTS-PP1 Prevents Transcription-Replication Conflicts by Promoting RNA Polymerase II Degradation on Chromatin. Cell Rep 2020; 33:108469. [PMID: 33264625 DOI: 10.1016/j.celrep.2020.108469] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 10/05/2020] [Accepted: 11/10/2020] [Indexed: 02/08/2023] Open
Abstract
Transcription-replication (T-R) conflicts cause replication stress and loss of genome integrity. However, the transcription-related processes that restrain such conflicts are poorly understood. Here, we demonstrate that the RNA polymerase II (RNAPII) C-terminal domain (CTD) phosphatase protein phosphatase 1 (PP1) nuclear targeting subunit (PNUTS)-PP1 inhibits replication stress. Depletion of PNUTS causes lower EdU uptake, S phase accumulation, and slower replication fork rates. In addition, the PNUTS binding partner WDR82 also promotes RNAPII-CTD dephosphorylation and suppresses replication stress. RNAPII has a longer residence time on chromatin after depletion of PNUTS or WDR82. Furthermore, the RNAPII residence time is greatly enhanced by proteasome inhibition in control cells but less so in PNUTS- or WDR82-depleted cells, indicating that PNUTS and WDR82 promote degradation of RNAPII on chromatin. Notably, reduced replication is dependent on transcription and the phospho-CTD binding protein CDC73 after depletion of PNUTS/WDR82. Altogether, our results suggest that RNAPII-CTD dephosphorylation is required for the continuous turnover of RNAPII on chromatin, thereby preventing T-R conflicts.
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50
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Shan CM, Bao K, Diedrich J, Chen X, Lu C, Yates JR, Jia S. The INO80 Complex Regulates Epigenetic Inheritance of Heterochromatin. Cell Rep 2020; 33:108561. [PMID: 33378674 PMCID: PMC7896557 DOI: 10.1016/j.celrep.2020.108561] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/31/2020] [Accepted: 12/03/2020] [Indexed: 12/21/2022] Open
Abstract
One key aspect of epigenetic inheritance is that chromatin structures can be stably inherited through generations after the removal of the signals that establish such structures. In fission yeast, the RNA interference (RNAi) pathway is critical for the targeting of histone methyltransferase Clr4 to pericentric repeats to establish heterochromatin. However, pericentric heterochromatin cannot be properly inherited in the absence of RNAi, suggesting the existence of mechanisms that counteract chromatin structure inheritance. Here, we show that mutations of components of the INO80 chromatin-remodeling complex allow pericentric heterochromatin inheritance in RNAi mutants. The ability of INO80 to counter heterochromatin inheritance is attributed to one subunit, Iec5, which promotes histone turnover at heterochromatin but has little effects on nucleosome positioning at heterochromatin, gene expression, or the DNA damage response. These analyses demonstrate the importance of the INO80 chromatin-remodeling complex in controlling heterochromatin inheritance and maintaining the proper heterochromatin landscape of the genome.
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Affiliation(s)
- Chun-Min Shan
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Kehan Bao
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Jolene Diedrich
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Xiao Chen
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Chao Lu
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA; Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - John R Yates
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Songtao Jia
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
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