101
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Basar MA, Beck DB, Werner A. Deubiquitylases in developmental ubiquitin signaling and congenital diseases. Cell Death Differ 2021; 28:538-556. [PMID: 33335288 PMCID: PMC7862630 DOI: 10.1038/s41418-020-00697-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 02/06/2023] Open
Abstract
Metazoan development from a one-cell zygote to a fully formed organism requires complex cellular differentiation and communication pathways. To coordinate these processes, embryos frequently encode signaling information with the small protein modifier ubiquitin, which is typically attached to lysine residues within substrates. During ubiquitin signaling, a three-step enzymatic cascade modifies specific substrates with topologically unique ubiquitin modifications, which mediate changes in the substrate's stability, activity, localization, or interacting proteins. Ubiquitin signaling is critically regulated by deubiquitylases (DUBs), a class of ~100 human enzymes that oppose the conjugation of ubiquitin. DUBs control many essential cellular functions and various aspects of human physiology and development. Recent genetic studies have identified mutations in several DUBs that cause developmental disorders. Here we review principles controlling DUB activity and substrate recruitment that allow these enzymes to regulate ubiquitin signaling during development. We summarize key mechanisms of how DUBs control embryonic and postnatal differentiation processes, highlight developmental disorders that are caused by mutations in particular DUB members, and describe our current understanding of how these mutations disrupt development. Finally, we discuss how emerging tools from human disease genetics will enable the identification and study of novel congenital disease-causing DUBs.
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Affiliation(s)
- Mohammed A Basar
- Stem Cell Biochemistry Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - David B Beck
- Stem Cell Biochemistry Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
- Metabolic, Cardiovascular and Inflammatory Disease Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Achim Werner
- Stem Cell Biochemistry Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA.
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102
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Grau D, Zhang Y, Lee CH, Valencia-Sánchez M, Zhang J, Wang M, Holder M, Svetlov V, Tan D, Nudler E, Reinberg D, Walz T, Armache KJ. Structures of monomeric and dimeric PRC2:EZH1 reveal flexible modules involved in chromatin compaction. Nat Commun 2021; 12:714. [PMID: 33514705 PMCID: PMC7846606 DOI: 10.1038/s41467-020-20775-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 12/18/2020] [Indexed: 01/02/2023] Open
Abstract
Polycomb repressive complex 2 (PRC2) is a histone methyltransferase critical for maintaining gene silencing during eukaryotic development. In mammals, PRC2 activity is regulated in part by the selective incorporation of one of two paralogs of the catalytic subunit, EZH1 or EZH2. Each of these enzymes has specialized biological functions that may be partially explained by differences in the multivalent interactions they mediate with chromatin. Here, we present two cryo-EM structures of PRC2:EZH1, one as a monomer and a second one as a dimer bound to a nucleosome. When bound to nucleosome substrate, the PRC2:EZH1 dimer undergoes a dramatic conformational change. We demonstrate that mutation of a divergent EZH1/2 loop abrogates the nucleosome-binding and methyltransferase activities of PRC2:EZH1. Finally, we show that PRC2:EZH1 dimers are more effective than monomers at promoting chromatin compaction, and the divergent EZH1/2 loop is essential for this function, thereby tying together the methyltransferase, nucleosome-binding, and chromatin-compaction activities of PRC2:EZH1. We speculate that the conformational flexibility and the ability to dimerize enable PRC2 to act on the varied chromatin substrates it encounters in the cell. Polycomb Repressive Complex 2 (PRC2) is a histone methyltransferase whose silencing activity is regulated in part by the selective incorporation of its catalytic subunits EZH1 or EZH2. Here, the authors capture an EZH1-containing PRC2 dimer on a nucleosome, demonstrating significant conformational changes during the process.
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Affiliation(s)
- Daniel Grau
- Skirball Institute of Biomolecular Medicine, Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA
| | - Yixiao Zhang
- Laboratory of Molecular Electron Microscopy, The Rockefeller University, New York, NY, USA
| | - Chul-Hwan Lee
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA.,Department of Pharmacology, Seoul National University, Seoul, Republic of Korea
| | - Marco Valencia-Sánchez
- Skirball Institute of Biomolecular Medicine, Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA
| | - Jenny Zhang
- Skirball Institute of Biomolecular Medicine, Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA
| | - Miao Wang
- Skirball Institute of Biomolecular Medicine, Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA
| | - Marlene Holder
- Skirball Institute of Biomolecular Medicine, Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA
| | - Vladimir Svetlov
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Dongyan Tan
- Department of Pharmacological Sciences, Stony Brook University Medical School, Stony Brook, NY, USA
| | - Evgeny Nudler
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Danny Reinberg
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Thomas Walz
- Laboratory of Molecular Electron Microscopy, The Rockefeller University, New York, NY, USA.
| | - Karim-Jean Armache
- Skirball Institute of Biomolecular Medicine, Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA.
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103
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Emerging multifaceted roles of BAP1 complexes in biological processes. Cell Death Dis 2021; 7:20. [PMID: 33483476 PMCID: PMC7822832 DOI: 10.1038/s41420-021-00406-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 10/28/2020] [Accepted: 11/30/2020] [Indexed: 01/30/2023]
Abstract
Histone H2AK119 mono-ubiquitination (H2AK119Ub) is a relatively abundant histone modification, mainly catalyzed by the Polycomb Repressive Complex 1 (PRC1) to regulate Polycomb-mediated transcriptional repression of downstream target genes. Consequently, H2AK119Ub can also be dynamically reversed by the BAP1 complex, an evolutionarily conserved multiprotein complex that functions as a general transcriptional activator. In previous studies, it has been reported that the BAP1 complex consists of important biological roles in development, metabolism, and cancer. However, identifying the BAP1 complex's regulatory mechanisms remains to be elucidated due to its various complex forms and its ability to target non-histone substrates. In this review, we will summarize recent findings that have contributed to the diverse functional role of the BAP1 complex and further discuss the potential in targeting BAP1 for therapeutic use.
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104
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Boeren J, Gribnau J. Xist-mediated chromatin changes that establish silencing of an entire X chromosome in mammals. Curr Opin Cell Biol 2020; 70:44-50. [PMID: 33360102 DOI: 10.1016/j.ceb.2020.11.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/17/2020] [Accepted: 11/22/2020] [Indexed: 12/19/2022]
Abstract
X chromosome inactivation (XCI) ensures an equal gene dosage between the sexes in placental mammals. Xist, a modular multi-domain X-encoded long non-coding RNA coats the X chromosome in cis during XCI. Xist recruits chromatin remodelers and repressor complexes ensuring silencing of the inactive X (Xi). Here, we review the recent work focused on the role of Xist functional repeats and interacting RNA-binding factors in the establishment of the silent state. Xist orchestrates recruitment of remodelers and repressors that first facilitate removal of the active chromatin landscape and subsequently direct the transition into a repressive heterochromatic environment. Some of these factors affect silencing on a chromosome-wide scale, while others display gene-specific silencing defects. The temporal order of recruitment shows each silencing step is party dependent on one another. After the Xi is established, many of the factors are dispensable, and a different repertoire of proteins ensure the silenced Xi is maintained and propagated.
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Affiliation(s)
- Jeffrey Boeren
- Department of Developmental Biology, Erasmus University Medical Center, the Netherlands; Oncode Institute, Erasmus University Medical Center, the Netherlands
| | - Joost Gribnau
- Department of Developmental Biology, Erasmus University Medical Center, the Netherlands; Oncode Institute, Erasmus University Medical Center, the Netherlands.
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105
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Liu X. A Structural Perspective on Gene Repression by Polycomb Repressive Complex 2. Subcell Biochem 2020; 96:519-562. [PMID: 33252743 DOI: 10.1007/978-3-030-58971-4_17] [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: 03/30/2023]
Abstract
Polycomb Repressive Complex 2 (PRC2) is a major repressive chromatin complex formed by the Polycomb Group (PcG) proteins. PRC2 mediates trimethylation of histone H3 lysine 27 (H3K27me3), a hallmark of gene silencing. PRC2 is a key regulator of development, impacting many fundamental biological processes, like stem cell differentiation in mammals and vernalization in plants. Misregulation of PRC2 function is linked to a variety of human cancers and developmental disorders. In correlation with its diverse roles in development, PRC2 displays a high degree of compositional complexity and plasticity. Structural biology research over the past decade has shed light on the molecular mechanisms of the assembly, catalysis, allosteric activation, autoinhibition, chemical inhibition, dimerization and chromatin targeting of various developmentally regulated PRC2 complexes. In addition to these aspects, structure-function analysis is also discussed in connection with disease data in this chapter.
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Affiliation(s)
- Xin Liu
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, UT Southwestern Medical Center, Dallas, TX, 75390, USA.
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106
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Reevaluating the roles of histone-modifying enzymes and their associated chromatin modifications in transcriptional regulation. Nat Genet 2020; 52:1271-1281. [PMID: 33257899 DOI: 10.1038/s41588-020-00736-4] [Citation(s) in RCA: 178] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 10/08/2020] [Indexed: 12/14/2022]
Abstract
Histone-modifying enzymes are implicated in the control of diverse DNA-templated processes including gene expression. Here, we outline historical and current thinking regarding the functions of histone modifications and their associated enzymes. One current viewpoint, based largely on correlative evidence, posits that histone modifications are instructive for transcriptional regulation and represent an epigenetic 'code'. Recent studies have challenged this model and suggest that histone marks previously associated with active genes do not directly cause transcriptional activation. Additionally, many histone-modifying proteins possess non-catalytic functions that overshadow their enzymatic activities. Given that much remains unknown regarding the functions of these proteins, the field should be cautious in interpreting loss-of-function phenotypes and must consider both cellular and developmental context. In this Perspective, we focus on recent progress relating to the catalytic and non-catalytic functions of the Trithorax-COMPASS complexes, Polycomb repressive complexes and Clr4/Suv39 histone-modifying machineries.
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107
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Polycomb group-mediated histone H2A monoubiquitination in epigenome regulation and nuclear processes. Nat Commun 2020; 11:5947. [PMID: 33230107 PMCID: PMC7683540 DOI: 10.1038/s41467-020-19722-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 10/12/2020] [Indexed: 12/19/2022] Open
Abstract
Histone posttranslational modifications are key regulators of chromatin-associated processes including gene expression, DNA replication and DNA repair. Monoubiquitinated histone H2A, H2Aub (K118 in Drosophila or K119 in vertebrates) is catalyzed by the Polycomb group (PcG) repressive complex 1 (PRC1) and reversed by the PcG-repressive deubiquitinase (PR-DUB)/BAP1 complex. Here we critically assess the current knowledge regarding H2Aub deposition and removal, its crosstalk with PcG repressive complex 2 (PRC2)-mediated histone H3K27 methylation, and the recent attempts toward discovering its readers and solving its enigmatic functions. We also discuss mounting evidence of the involvement of H2A ubiquitination in human pathologies including cancer, while highlighting some knowledge gaps that remain to be addressed. Histone H2A monoubiquitination on lysine 119 in vertebrate and lysine 118 in Drosophila (H2Aub) is an epigenomic mark usually associated with gene repression by Polycomb group factors. Here the authors review the current knowledge on the deposition and removal of H2Aub, its function in transcription and other DNA-associated processes as well as its relevance to human disease.
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108
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Structural basis for PRC2 engagement with chromatin. Curr Opin Struct Biol 2020; 67:135-144. [PMID: 33232890 DOI: 10.1016/j.sbi.2020.10.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/14/2020] [Accepted: 10/19/2020] [Indexed: 02/08/2023]
Abstract
The polycomb repressive complex 2 (PRC2) is a conserved multiprotein, repressive chromatin complex essential for development and maintenance of eukaryotic cellular identity. PRC2 comprises a trimeric core of SUZ12, EED and EZH1/2, which together with RBBP4/7 is sufficient to catalyse mono-methylation, di-methylation and tri-methylation of histone H3 at lysine 27 (H3K27me1/2/3). These histone methyltransferase activities of PRC2 are deregulated in several human cancers and certain developmental disorders, such as Weaver Syndrome. Core PRC2 associates with several accessory proteins, which organise to define two main subassemblies, PRC2.1 and PRC2.2. Here we review new biochemical and structural studies that are providing critical insights into how core and accessory PRC2 subunits coordinate the faithful deposition of H3K27 methylations genome-wide.
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109
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Geng Z, Gao Z. Mammalian PRC1 Complexes: Compositional Complexity and Diverse Molecular Mechanisms. Int J Mol Sci 2020; 21:E8594. [PMID: 33202645 PMCID: PMC7697839 DOI: 10.3390/ijms21228594] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/13/2022] Open
Abstract
Polycomb group (PcG) proteins function as vital epigenetic regulators in various biological processes, including pluripotency, development, and carcinogenesis. PcG proteins form multicomponent complexes, and two major types of protein complexes have been identified in mammals to date, Polycomb Repressive Complexes 1 and 2 (PRC1 and PRC2). The PRC1 complexes are composed in a hierarchical manner in which the catalytic core, RING1A/B, exclusively interacts with one of six Polycomb group RING finger (PCGF) proteins. This association with specific PCGF proteins allows for PRC1 to be subdivided into six distinct groups, each with their own unique modes of action arising from the distinct set of associated proteins. Historically, PRC1 was considered to be a transcription repressor that deposited monoubiquitylation of histone H2A at lysine 119 (H2AK119ub1) and compacted local chromatin. More recently, there is increasing evidence that demonstrates the transcription activation role of PRC1. Moreover, studies on the higher-order chromatin structure have revealed a new function for PRC1 in mediating long-range interactions. This provides a different perspective regarding both the transcription activation and repression characteristics of PRC1. This review summarizes new advancements regarding the composition of mammalian PRC1 and accompanying explanations of how diverse PRC1-associated proteins participate in distinct transcription regulation mechanisms.
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Affiliation(s)
- Zhuangzhuang Geng
- Departments of Biochemistry and Molecular Biology, Penn State College of Medicine, Hershey, PA 17033, USA;
| | - Zhonghua Gao
- Departments of Biochemistry and Molecular Biology, Penn State College of Medicine, Hershey, PA 17033, USA;
- Penn State Hershey Cancer Institute, Hershey, PA 17033, USA
- The Stem Cell and Regenerative Biology Program, Penn State College of Medicine, Hershey, PA 17033, USA
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110
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Martin CJ, Moorehead RA. Polycomb repressor complex 2 function in breast cancer (Review). Int J Oncol 2020; 57:1085-1094. [PMID: 33491744 PMCID: PMC7549536 DOI: 10.3892/ijo.2020.5122] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 09/07/2020] [Indexed: 11/24/2022] Open
Abstract
Epigenetic modifications are important contributors to the regulation of genes within the chromatin. The polycomb repressive complex 2 (PRC2) is a multi‑subunit protein complex that is involved in silencing gene expression through the trimethylation of lysine 27 at histone 3 (H3K27me3). The dysregulation of this modification has been associated with tumorigenicity through the increased repression of tumour suppressor genes via condensing DNA to reduce access to the transcription start site (TSS) within tumor suppressor gene promoters. In the present review, the core proteins of PRC2, as well as key accessory proteins, will be described. In addition, mechanisms controlling the recruitment of the PRC2 complex to H3K27 will be outlined. Finally, literature identifying the role of PRC2 in breast cancer proliferation, apoptosis and migration, including the potential roles of long non‑coding RNAs and the miR‑200 family will be summarized as will the potential use of the PRC2 complex as a therapeutic target.
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Affiliation(s)
- Courtney J. Martin
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON N1G2W1, Canada
| | - Roger A. Moorehead
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON N1G2W1, Canada
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111
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Hu E, Du H, Shang S, Zhang Y, Lu X. Beta-Hydroxybutyrate Enhances BDNF Expression by Increasing H3K4me3 and Decreasing H2AK119ub in Hippocampal Neurons. Front Neurosci 2020; 14:591177. [PMID: 33192276 PMCID: PMC7655964 DOI: 10.3389/fnins.2020.591177] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/12/2020] [Indexed: 12/18/2022] Open
Abstract
Neurological evidence suggests that beta-hydroxybutyrate (BHBA) has positive effects on the central nervous system. Previous studies have explored the molecular mechanisms by which BHBA affects different brain functions, but the effects of BHBA on epigenetic modifications remain elusive. Here, we showed that BHBA enhanced brain-derived neurotrophic factor (BDNF) expression by increasing H3K4me3 and decreasing H2AK119ub occupancy at the Bdnf promoters I, II, IV, and VI in hippocampal neurons. Moreover, BHBA treatment induced the upregulation of H3K4me3 and downregulation of H2AK119ub on the global level, both of which were dependent on the L-type calcium channel. Additionally, the BHBA-activated L-type calcium channel subsequently triggered the activation of Ca2+/CaMKII/CREB signaling, and promoted the binding of p-CREB and CBP to Bdnf promoters. These results indicate that BHBA regulates cellular signaling and multiple histone modifications to cooperatively modulate BDNF, suggesting a wide range of regulatory effects of BHBA in the central nervous system.
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Affiliation(s)
- Erling Hu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Sciences and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Huan Du
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Sciences and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Sen Shang
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Sciences and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Yali Zhang
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Sciences and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Xiaoyun Lu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Sciences and Technology, Xi'an Jiaotong University, Xi'an, China
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112
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Varlet E, Ovejero S, Martinez AM, Cavalli G, Moreaux J. Role of Polycomb Complexes in Normal and Malignant Plasma Cells. Int J Mol Sci 2020; 21:ijms21218047. [PMID: 33126754 PMCID: PMC7662980 DOI: 10.3390/ijms21218047] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 10/26/2020] [Accepted: 10/26/2020] [Indexed: 02/01/2023] Open
Abstract
Plasma cells (PC) are the main effectors of adaptive immunity, responsible for producing antibodies to defend the body against pathogens. They are the result of a complex highly regulated cell differentiation process, taking place in several anatomical locations and involving unique genetic events. Pathologically, PC can undergo tumorigenesis and cause a group of diseases known as plasma cell dyscrasias, including multiple myeloma (MM). MM is a severe disease with poor prognosis that is characterized by the accumulation of malignant PC within the bone marrow, as well as high clinical and molecular heterogeneity. MM patients frequently develop resistance to treatment, leading to relapse. Polycomb group (PcG) proteins are epigenetic regulators involved in cell fate and carcinogenesis. The emerging roles of PcG in PC differentiation and myelomagenesis position them as potential therapeutic targets in MM. Here, we focus on the roles of PcG proteins in normal and malignant plasma cells, as well as their therapeutic implications.
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Affiliation(s)
- Emmanuel Varlet
- Institute of Human Genetics, UMR 9002 Centre National de la Recherche Scientifique, University of Montpellier, Montpellier, 34396 Montpellier, France; (E.V.); (S.O.); (A.-M.M.); (G.C.)
| | - Sara Ovejero
- Institute of Human Genetics, UMR 9002 Centre National de la Recherche Scientifique, University of Montpellier, Montpellier, 34396 Montpellier, France; (E.V.); (S.O.); (A.-M.M.); (G.C.)
- Department of Biological Hematology, CHU Montpellier, 34295 Montpellier, France
| | - Anne-Marie Martinez
- Institute of Human Genetics, UMR 9002 Centre National de la Recherche Scientifique, University of Montpellier, Montpellier, 34396 Montpellier, France; (E.V.); (S.O.); (A.-M.M.); (G.C.)
| | - Giacomo Cavalli
- Institute of Human Genetics, UMR 9002 Centre National de la Recherche Scientifique, University of Montpellier, Montpellier, 34396 Montpellier, France; (E.V.); (S.O.); (A.-M.M.); (G.C.)
| | - Jerome Moreaux
- Institute of Human Genetics, UMR 9002 Centre National de la Recherche Scientifique, University of Montpellier, Montpellier, 34396 Montpellier, France; (E.V.); (S.O.); (A.-M.M.); (G.C.)
- Department of Biological Hematology, CHU Montpellier, 34295 Montpellier, France
- UFR Medicine, University of Montpellier, 34003 Montpellier, France
- Institut Universitaire de France (IUF), 75005 Paris, France
- Correspondence: ; Tel.: +33-04-6733-7903
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113
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Das P, Taube JH. Regulating Methylation at H3K27: A Trick or Treat for Cancer Cell Plasticity. Cancers (Basel) 2020; 12:E2792. [PMID: 33003334 PMCID: PMC7600873 DOI: 10.3390/cancers12102792] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 09/21/2020] [Accepted: 09/23/2020] [Indexed: 12/13/2022] Open
Abstract
Properly timed addition and removal of histone 3 lysine 27 tri-methylation (H3K27me3) is critical for enabling proper differentiation throughout all stages of development and, likewise, can guide carcinoma cells into altered differentiation states which correspond to poor prognoses and treatment evasion. In early embryonic stages, H3K27me3 is invoked to silence genes and restrict cell fate. Not surprisingly, mutation or altered functionality in the enzymes that regulate this pathway results in aberrant methylation or demethylation that can lead to malignancy. Likewise, changes in expression or activity of these enzymes impact cellular plasticity, metastasis, and treatment evasion. This review focuses on current knowledge regarding methylation and de-methylation of H3K27 in cancer initiation and cancer cell plasticity.
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Affiliation(s)
| | - Joseph H. Taube
- Department of Biology, Baylor University, Waco, TX 76706, USA;
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114
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Skrajna A, Goldfarb D, Kedziora KM, Cousins E, Grant GD, Spangler CJ, Barbour EH, Yan X, Hathaway NA, Brown NG, Cook JG, Major MB, McGinty RK. Comprehensive nucleosome interactome screen establishes fundamental principles of nucleosome binding. Nucleic Acids Res 2020; 48:9415-9432. [PMID: 32658293 PMCID: PMC7515726 DOI: 10.1093/nar/gkaa544] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/03/2020] [Accepted: 06/17/2020] [Indexed: 02/03/2023] Open
Abstract
Nuclear proteins bind chromatin to execute and regulate genome-templated processes. While studies of individual nucleosome interactions have suggested that an acidic patch on the nucleosome disk may be a common site for recruitment to chromatin, the pervasiveness of acidic patch binding and whether other nucleosome binding hot-spots exist remain unclear. Here, we use nucleosome affinity proteomics with a library of nucleosomes that disrupts all exposed histone surfaces to comprehensively assess how proteins recognize nucleosomes. We find that the acidic patch and two adjacent surfaces are the primary hot-spots for nucleosome disk interactions, whereas nearly half of the nucleosome disk participates only minimally in protein binding. Our screen defines nucleosome surface requirements of nearly 300 nucleosome interacting proteins implicated in diverse nuclear processes including transcription, DNA damage repair, cell cycle regulation and nuclear architecture. Building from our screen, we demonstrate that the Anaphase-Promoting Complex/Cyclosome directly engages the acidic patch, and we elucidate a redundant mechanism of acidic patch binding by nuclear pore protein ELYS. Overall, our interactome screen illuminates a highly competitive nucleosome binding hub and establishes universal principles of nucleosome recognition.
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Affiliation(s)
- Aleksandra Skrajna
- Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, Chapel Hill, NC, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
| | - Dennis Goldfarb
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Computer Science, University of North Carolina, Chapel Hill, NC, USA
| | - Katarzyna M Kedziora
- Computational Medicine Program, University of North Carolina, Chapel Hill, NC, USA
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Emily M Cousins
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
| | - Gavin D Grant
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, USA
| | - Cathy J Spangler
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, USA
| | - Emily H Barbour
- Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Xiaokang Yan
- Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Nathaniel A Hathaway
- Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, Chapel Hill, NC, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
| | - Nicholas G Brown
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Jeanette G Cook
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, USA
| | - Michael B Major
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Robert K McGinty
- Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, Chapel Hill, NC, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, USA
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115
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The genetic basis for PRC1 complex diversity emerged early in animal evolution. Proc Natl Acad Sci U S A 2020; 117:22880-22889. [PMID: 32868440 DOI: 10.1073/pnas.2005136117] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Polycomb group proteins are essential regulators of developmental processes across animals. Despite their importance, studies on Polycomb are often restricted to classical model systems and, as such, little is known about the evolution of these important chromatin regulators. Here we focus on Polycomb Repressive Complex 1 (PRC1) and trace the evolution of core components of canonical and non-canonical PRC1 complexes in animals. Previous work suggested that a major expansion in the number of PRC1 complexes occurred in the vertebrate lineage. We show that the expansion of the Polycomb Group RING Finger (PCGF) protein family, an essential step for the establishment of the large diversity of PRC1 complexes found in vertebrates, predates the bilaterian-cnidarian ancestor. This means that the genetic repertoire necessary to form all major vertebrate PRC1 complexes emerged early in animal evolution, over 550 million years ago. We further show that PCGF5, a gene conserved in cnidarians and vertebrates but lost in all other studied groups, is expressed in the nervous system in the sea anemone Nematostella vectensis, similar to its mammalian counterpart. Together this work provides a framework for understanding the evolution of PRC1 complex diversity and it establishes Nematostella as a promising model system in which the functional ramifications of this diversification can be further explored.
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116
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Giner-Laguarda N, Vidal M. Functions of Polycomb Proteins on Active Targets. EPIGENOMES 2020; 4:17. [PMID: 34968290 PMCID: PMC8594714 DOI: 10.3390/epigenomes4030017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 08/12/2020] [Accepted: 08/13/2020] [Indexed: 12/15/2022] Open
Abstract
Chromatin regulators of the Polycomb group of genes are well-known by their activities as transcriptional repressors. Characteristically, their presence at genomic sites occurs with specific histone modifications and sometimes high-order chromatin structures correlated with silencing of genes involved in cell differentiation. However, evidence gathered in recent years, on flies and mammals, shows that in addition to these sites, Polycomb products bind to a large number of active regulatory regions. Occupied sites include promoters and also intergenic regions, containing enhancers and super-enhancers. Contrasting with occupancies at repressed targets, characteristic histone modifications are low or undetectable. Functions on active targets are dual, restraining gene expression at some targets while promoting activity at others. Our aim here is to summarize the evidence available and discuss the convenience of broadening the scope of research to include Polycomb functions on active targets.
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Affiliation(s)
| | - Miguel Vidal
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas Margarita Salas, Ramiro de Maeztu 9, 28040 Madrid, Spain;
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117
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DeLuca SZ, Ghildiyal M, Pang LY, Spradling AC. Differentiating Drosophila female germ cells initiate Polycomb silencing by regulating PRC2-interacting proteins. eLife 2020; 9:56922. [PMID: 32773039 PMCID: PMC7438113 DOI: 10.7554/elife.56922] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 08/06/2020] [Indexed: 01/18/2023] Open
Abstract
Polycomb silencing represses gene expression and provides a molecular memory of chromatin state that is essential for animal development. We show that Drosophila female germline stem cells (GSCs) provide a powerful system for studying Polycomb silencing. GSCs have a non-canonical distribution of PRC2 activity and lack silenced chromatin like embryonic progenitors. As GSC daughters differentiate into nurse cells and oocytes, nurse cells, like embryonic somatic cells, silence genes in traditional Polycomb domains and in generally inactive chromatin. Developmentally controlled expression of two Polycomb repressive complex 2 (PRC2)-interacting proteins, Pcl and Scm, initiate silencing during differentiation. In GSCs, abundant Pcl inhibits PRC2-dependent silencing globally, while in nurse cells Pcl declines and newly induced Scm concentrates PRC2 activity on traditional Polycomb domains. Our results suggest that PRC2-dependent silencing is developmentally regulated by accessory proteins that either increase the concentration of PRC2 at target sites or inhibit the rate that PRC2 samples chromatin.
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Affiliation(s)
- Steven Z DeLuca
- Howard Hughes Medical Institute Research Laboratories Department of Embryology, Carnegie Institution for Science, Baltimore, United States
| | - Megha Ghildiyal
- Howard Hughes Medical Institute Research Laboratories Department of Embryology, Carnegie Institution for Science, Baltimore, United States
| | - Liang-Yu Pang
- Howard Hughes Medical Institute Research Laboratories Department of Embryology, Carnegie Institution for Science, Baltimore, United States
| | - Allan C Spradling
- Howard Hughes Medical Institute Research Laboratories Department of Embryology, Carnegie Institution for Science, Baltimore, United States
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118
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Perino M, van Mierlo G, Loh C, Wardle SMT, Zijlmans DW, Marks H, Veenstra GJC. Two Functional Axes of Feedback-Enforced PRC2 Recruitment in Mouse Embryonic Stem Cells. Stem Cell Reports 2020; 15:1287-1300. [PMID: 32763159 PMCID: PMC7724473 DOI: 10.1016/j.stemcr.2020.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/22/2022] Open
Abstract
Polycomb Repressive Complex 2 (PRC2) plays an essential role in gene repression during development, catalyzing H3 lysine 27 trimethylation (H3K27me3). MTF2 in the PRC2.1 sub-complex, and JARID2 in PRC2.2, are central in core PRC2 recruitment to target genes in mouse embryonic stem cells (mESCs). To investigate how PRC2.1 and PRC2.2 cooperate, we combined Polycomb mutant mESCs with chemical inhibition of binding to H3K27me3. We find that PRC2.1 and PRC2.2 mediate two distinct paths for recruitment, which are mutually reinforced. Whereas PRC2.1 recruitment is mediated by MTF2 binding to DNA, JARID2-containing PRC2.2 recruitment is more dependent on PRC1. Both recruitment axes are supported by core subunit EED binding to H3K27me3, but EED inhibition exhibits a more pronounced effect in Jarid2 null cells. Finally, we show that PRC1 and PRC2 enhance reciprocal binding. Together, these data disentangle the interdependent interactions that are important for PRC2 recruitment.
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Affiliation(s)
- Matteo Perino
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands
| | - Guido van Mierlo
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands
| | - Chet Loh
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands
| | - Sandra M T Wardle
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands
| | - Dick W Zijlmans
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands
| | - Hendrik Marks
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands.
| | - Gert Jan C Veenstra
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands.
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119
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Regulation of Histone Ubiquitination in Response to DNA Double Strand Breaks. Cells 2020; 9:cells9071699. [PMID: 32708614 PMCID: PMC7407225 DOI: 10.3390/cells9071699] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/10/2020] [Accepted: 07/14/2020] [Indexed: 12/11/2022] Open
Abstract
Eukaryotic cells are constantly exposed to both endogenous and exogenous stressors that promote the induction of DNA damage. Of this damage, double strand breaks (DSBs) are the most lethal and must be efficiently repaired in order to maintain genomic integrity. Repair of DSBs occurs primarily through one of two major pathways: non-homologous end joining (NHEJ) or homologous recombination (HR). The choice between these pathways is in part regulated by histone post-translational modifications (PTMs) including ubiquitination. Ubiquitinated histones not only influence transcription and chromatin architecture at sites neighboring DSBs but serve as critical recruitment platforms for repair machinery as well. The reversal of these modifications by deubiquitinating enzymes (DUBs) is increasingly being recognized in a number of cellular processes including DSB repair. In this context, DUBs ensure proper levels of ubiquitin, regulate recruitment of downstream effectors, dictate repair pathway choice, and facilitate appropriate termination of the repair response. This review outlines the current understanding of histone ubiquitination in response to DSBs, followed by a comprehensive overview of the DUBs that catalyze the removal of these marks.
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120
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Abstract
Predicting regulatory potential from primary DNA sequences or transcription factor binding patterns is not possible. However, the annotation of the genome by chromatin proteins, histone modifications, and differential compaction is largely sufficient to reveal the locations of genes and their differential activity states. The Polycomb Group (PcG) and Trithorax Group (TrxG) proteins are the central players in this cell type-specific chromatin organization. PcG function was originally viewed as being solely repressive and irreversible, as observed at the homeotic loci in flies and mammals. However, it is now clear that modular and reversible PcG function is essential at most developmental genes. Focusing mainly on recent advances, we review evidence for how PcG and TrxG patterns change dynamically during cell type transitions. The ability to implement cell type-specific transcriptional programming with exquisite fidelity is essential for normal development.
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Affiliation(s)
- Mitzi I Kuroda
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA; ,
| | - Hyuckjoon Kang
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA; ,
| | - Sandip De
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA; ,
| | - Judith A Kassis
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA; ,
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121
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Ridenour JB, Möller M, Freitag M. Polycomb Repression without Bristles: Facultative Heterochromatin and Genome Stability in Fungi. Genes (Basel) 2020; 11:E638. [PMID: 32527036 PMCID: PMC7348808 DOI: 10.3390/genes11060638] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/27/2020] [Accepted: 06/04/2020] [Indexed: 02/06/2023] Open
Abstract
Genome integrity is essential to maintain cellular function and viability. Consequently, genome instability is frequently associated with dysfunction in cells and associated with plant, animal, and human diseases. One consequence of relaxed genome maintenance that may be less appreciated is an increased potential for rapid adaptation to changing environments in all organisms. Here, we discuss evidence for the control and function of facultative heterochromatin, which is delineated by methylation of histone H3 lysine 27 (H3K27me) in many fungi. Aside from its relatively well understood role in transcriptional repression, accumulating evidence suggests that H3K27 methylation has an important role in controlling the balance between maintenance and generation of novelty in fungal genomes. We present a working model for a minimal repressive network mediated by H3K27 methylation in fungi and outline challenges for future research.
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Affiliation(s)
| | | | - Michael Freitag
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis OR 97331, USA; (J.B.R.); (M.M.)
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122
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Boyle S, Flyamer IM, Williamson I, Sengupta D, Bickmore WA, Illingworth RS. A central role for canonical PRC1 in shaping the 3D nuclear landscape. Genes Dev 2020; 34:931-949. [PMID: 32439634 PMCID: PMC7328521 DOI: 10.1101/gad.336487.120] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 04/13/2020] [Indexed: 02/04/2023]
Abstract
In this study from Boyle et al., the authors investigated the role of Polycomb-repressive complex 1 (PRC1) in shaping 3D genome organization in mouse embryonic stem cells. Using a combination of imaging and Hi-C analyses they show that PRC1-mediated long-range interactions are independent of CTCF and can bridge sites at a megabase scale, thus providing novel insights into the function of PRC1. Polycomb group (PcG) proteins silence gene expression by chemically and physically modifying chromatin. A subset of PcG target loci are compacted and cluster in the nucleus; a conformation that is thought to contribute to gene silencing. However, how these interactions influence gross nuclear organization and their relationship with transcription remains poorly understood. Here we examine the role of Polycomb-repressive complex 1 (PRC1) in shaping 3D genome organization in mouse embryonic stem cells (mESCs). Using a combination of imaging and Hi-C analyses, we show that PRC1-mediated long-range interactions are independent of CTCF and can bridge sites at a megabase scale. Impairment of PRC1 enzymatic activity does not directly disrupt these interactions. We demonstrate that PcG targets coalesce in vivo, and that developmentally induced expression of one of the target loci disrupts this spatial arrangement. Finally, we show that transcriptional activation and the loss of PRC1-mediated interactions are separable events. These findings provide important insights into the function of PRC1, while highlighting the complexity of this regulatory system.
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Affiliation(s)
- Shelagh Boyle
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Ilya M Flyamer
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Iain Williamson
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Dipta Sengupta
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Wendy A Bickmore
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Robert S Illingworth
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
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123
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Mammalian CBX7 isoforms p36 and p22 exhibit differential responses to serum, varying functions for proliferation, and distinct subcellular localization. Sci Rep 2020; 10:8061. [PMID: 32415167 PMCID: PMC7228926 DOI: 10.1038/s41598-020-64908-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/20/2020] [Indexed: 01/04/2023] Open
Abstract
CBX7 is a polycomb group protein, and despite being implicated in many diseases, its role in cell proliferation has been controversial: some groups described its pro-proliferative properties, but others illustrated its inhibitory effects on cell growth. To date, the reason for the divergent observations remains unknown. While several isoforms for CBX7 were reported, no studies investigated whether the divergent roles of CBX7 could be due to distinct functions of CBX7 isoforms. In this study, we newly identified mouse CBX7 transcript variant 1 (mCbx7v1), which is homologous to the human CBX7 gene (hCBX7v1) and is expressed in various mouse organs. We revealed that mCbx7v1 and hCBX7v1 encode a 36 kDa protein (p36CBX7) whereas mCbx7 and hCBX7v3 encode a 22 kDa protein (p22CBX7). This study further demonstrated that p36CBX7 was localized to the nucleus and endogenously expressed in proliferating cells whereas p22CBX7 was localized to the cytoplasm, induced by serum starvation in both human and mouse cells, and inhibited cell proliferation. Together, these data indicate that CBX7 isoforms are localized in different locations in a cell and play differing roles in cell proliferation. This varying function of CBX7 isoforms may help us understand the distinct function of CBX7 in various studies.
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124
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Liu Z, Tardat M, Gill ME, Royo H, Thierry R, Ozonov EA, Peters AH. SUMOylated PRC1 controls histone H3.3 deposition and genome integrity of embryonic heterochromatin. EMBO J 2020; 39:e103697. [PMID: 32395866 PMCID: PMC7327501 DOI: 10.15252/embj.2019103697] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 04/09/2020] [Accepted: 04/14/2020] [Indexed: 12/14/2022] Open
Abstract
Chromatin integrity is essential for cellular homeostasis. Polycomb group proteins modulate chromatin states and transcriptionally repress developmental genes to maintain cell identity. They also repress repetitive sequences such as major satellites and constitute an alternative state of pericentromeric constitutive heterochromatin at paternal chromosomes (pat‐PCH) in mouse pre‐implantation embryos. Remarkably, pat‐PCH contains the histone H3.3 variant, which is absent from canonical PCH at maternal chromosomes, which is marked by histone H3 lysine 9 trimethylation (H3K9me3), HP1, and ATRX proteins. Here, we show that SUMO2‐modified CBX2‐containing Polycomb Repressive Complex 1 (PRC1) recruits the H3.3‐specific chaperone DAXX to pat‐PCH, enabling H3.3 incorporation at these loci. Deficiency of Daxx or PRC1 components Ring1 and Rnf2 abrogates H3.3 incorporation, induces chromatin decompaction and breakage at PCH of exclusively paternal chromosomes, and causes their mis‐segregation. Complementation assays show that DAXX‐mediated H3.3 deposition is required for chromosome stability in early embryos. DAXX also regulates repression of PRC1 target genes during oogenesis and early embryogenesis. The study identifies a novel critical role for Polycomb in ensuring heterochromatin integrity and chromosome stability in mouse early development.
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Affiliation(s)
- Zichuan Liu
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Mathieu Tardat
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Mark E Gill
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Helene Royo
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Raphael Thierry
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Evgeniy A Ozonov
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Antoine Hfm Peters
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Faculty of Sciences, University of Basel, Basel, Switzerland
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125
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Zhang X, Chen M, Liu X, Zhang L, Ding X, Guo Y, Li X, Guo H. A novel lncRNA, lnc403, involved in bovine skeletal muscle myogenesis by mediating KRAS/Myf6. Gene 2020; 751:144706. [PMID: 32387386 DOI: 10.1016/j.gene.2020.144706] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 03/05/2020] [Accepted: 04/21/2020] [Indexed: 02/07/2023]
Abstract
Skeletal muscle, the most abundant and plasticity tissue in mammals, is essential for various functions such as movement, breathing, maintaining posture and metabolism. Myogenesis is a complex and precise process, which is regulated by the sequential expression of multiple transcription factors, and accumulating evidence have confirmed that multiple lncRNAs are involved in muscle development as the important transcriptional regulator. In this study, a novel lncRNA, named lnc403 was obtained, with a full-length 2689 bp, which had poor coding ability and was mainly expressed in the nucleus of myoblasts and myotubes. The expression of lnc403 was significantly different in the proliferation and differentiation stages of muscle cells. Then we successfully constructed lnc403 loss/gain-function cell models by transfecting silnc403 and pCDNA3.1-EGFP-lnc403 into satellite cells, respectively; and found that lnc403 inhibited skeletal muscle satellite cell differentiation but had no significant effect on cell proliferation, either in the case of lnc403 knockdown or overexpression. In order to further screen the target factors regulated by lncRNA in the process of myogenic differentiation, the RNA-pull down, mass spectrometry and bioinformatics analysis were performed. The results showed that lnc403 negatively regulated the expression of the adjacent gene Myf6 and positively regulated interaction proteins KRAS expression. The above results indicate that lnc403 affects skeletal muscle cell differentiation by affecting the expression of nearby genes and interacting proteins, implying lnc403 might participate in the bovine myoblasts differentiation through multi-pathway network regulation mode. This study provides a new perspective for further understanding of the regulation mechanism of lncRNAs on bovine myogenic process.
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Affiliation(s)
- Xiaojuan Zhang
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China
| | - Mingming Chen
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China
| | - Xinfeng Liu
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China
| | - Linlin Zhang
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China
| | - Xiangbin Ding
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China
| | - Yiwen Guo
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China
| | - Xin Li
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China.
| | - Hong Guo
- Tianjin Key Laboratory of Agricultural Animal Breeding and Healthy Husbandry, College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China.
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126
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Cohen I, Bar C, Ezhkova E. Activity of PRC1 and Histone H2AK119 Monoubiquitination: Revising Popular Misconceptions. Bioessays 2020; 42:e1900192. [PMID: 32196702 PMCID: PMC7585675 DOI: 10.1002/bies.201900192] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/12/2020] [Indexed: 12/21/2022]
Abstract
Polycomb group proteins are evolutionary conserved chromatin-modifying complexes, essential for the regulation of developmental and cell-identity genes. Polycomb-mediated transcriptional regulation is provided by two multi-protein complexes known as Polycomb repressive complex 1 (PRC1) and 2 (PRC2). Recent studies positioned PRC1 as a foremost executer of Polycomb-mediated transcriptional control. Mammalian PRC1 complexes can form multiple sub-complexes that vary in their core and accessory subunit composition, leading to fascinating and diverse transcriptional regulatory mechanisms employed by PRC1 complexes. These mechanisms include PRC1-catalytic activity toward monoubiquitination of histone H2AK119, a well-established hallmark of PRC1 complexes, whose importance has been long debated. In this review, the central roles that PRC1-catalytic activity plays in transcriptional repression are emphasized and the recent evidence supporting a role for PRC1 complexes in gene activation is discussed.
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Affiliation(s)
- Idan Cohen
- The Shraga Segal Department of Microbiology, Immunology and Genetics; Faculty of Health Science; Ben-Gurion University of the Negev; Beer Sheva 84105; Israel
- These authors contributed equally to this work
| | - Carmit Bar
- Black Family Stem Cell Institute, Department of Cell, Developmental, and Regenerative Biology; Icahn School of Medicine at Mount Sinai; 1 Gustave L. Levy Place, New York, NY 10029; USA
- These authors contributed equally to this work
| | - Elena Ezhkova
- The Shraga Segal Department of Microbiology, Immunology and Genetics; Faculty of Health Science; Ben-Gurion University of the Negev; Beer Sheva 84105; Israel
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127
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Zhang Y, Shi J, Liu X, Xiao Z, Lei G, Lee H, Koppula P, Cheng W, Mao C, Zhuang L, Ma L, Li W, Gan B. H2A Monoubiquitination Links Glucose Availability to Epigenetic Regulation of the Endoplasmic Reticulum Stress Response and Cancer Cell Death. Cancer Res 2020; 80:2243-2256. [PMID: 32273282 DOI: 10.1158/0008-5472.can-19-3580] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/11/2020] [Accepted: 04/06/2020] [Indexed: 02/06/2023]
Abstract
Epigenetic regulation of gene transcription has been shown to coordinate with nutrient availability, yet the mechanisms underlying this coordination remain incompletely understood. Here, we show that glucose starvation suppresses histone 2A K119 monoubiquitination (H2Aub), a histone modification that correlates with gene repression. Glucose starvation suppressed H2Aub levels independently of energy stress-mediated AMP-activated protein kinase activation and possibly through NADPH depletion and subsequent inhibition of BMI1, an integral component of polycomb-repressive complex 1 (PRC1) that catalyzes H2Aub on chromatin. Integrated transcriptomic and epigenomic analyses linked glucose starvation-mediated H2Aub repression to the activation of genes involved in the endoplasmic reticulum (ER) stress response. We further showed that this epigenetic mechanism has a role in glucose starvation-induced cell death and that pharmacologic inhibition of glucose transporter 1 and PRC1 synergistically promoted ER stress and suppressed tumor growth in vivo. Together, these results reveal a hitherto unrecognized epigenetic mechanism coupling glucose availability to the ER stress response. SIGNIFICANCE: These findings link glucose deprivation and H2A ubiquitination to regulation of the ER stress response in tumor growth and demonstrate pharmacologic susceptibility to inhibition of polycomb and glucose transporters.
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Affiliation(s)
- Yilei Zhang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jiejun Shi
- Department of Biological Chemistry, University of California, Irvine, Irvine, California.,Division of Biostatistics, Dan L. Duncan Cancer Center and Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas
| | - Xiaoguang Liu
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Zhenna Xiao
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Guang Lei
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Hyemin Lee
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Pranavi Koppula
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.,The University of Texas MD Anderson UTHealth Graduate School of Biomedical Sciences, Houston, Texas
| | - Weijie Cheng
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Chao Mao
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Li Zhuang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Li Ma
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.,The University of Texas MD Anderson UTHealth Graduate School of Biomedical Sciences, Houston, Texas
| | - Wei Li
- Department of Biological Chemistry, University of California, Irvine, Irvine, California. .,Division of Biostatistics, Dan L. Duncan Cancer Center and Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas
| | - Boyi Gan
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. .,The University of Texas MD Anderson UTHealth Graduate School of Biomedical Sciences, Houston, Texas
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Zepeda-Martinez JA, Pribitzer C, Wang J, Bsteh D, Golumbeanu S, Zhao Q, Burkard TR, Reichholf B, Rhie SK, Jude J, Moussa HF, Zuber J, Bell O. Parallel PRC2/cPRC1 and vPRC1 pathways silence lineage-specific genes and maintain self-renewal in mouse embryonic stem cells. SCIENCE ADVANCES 2020; 6:eaax5692. [PMID: 32270030 PMCID: PMC7112768 DOI: 10.1126/sciadv.aax5692] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 01/09/2020] [Indexed: 05/29/2023]
Abstract
The transcriptional repressors Polycomb repressive complex 1 (PRC1) and PRC2 are required to maintain cell fate during embryonic development. PRC1 and PRC2 catalyze distinct histone modifications, establishing repressive chromatin at shared targets. How PRC1, which consists of canonical PRC1 (cPRC1) and variant PRC1 (vPRC1) complexes, and PRC2 cooperate to silence genes and support mouse embryonic stem cell (mESC) self-renewal is unclear. Using combinatorial genetic perturbations, we show that independent pathways of cPRC1 and vPRC1 are responsible for maintenance of H2A monoubiquitylation and silencing of shared target genes. Individual loss of PRC2-dependent cPRC1 or PRC2-independent vPRC1 disrupts only one pathway and does not impair mESC self-renewal capacity. However, loss of both pathways leads to mESC differentiation and activation of a subset of lineage-specific genes co-occupied by relatively high levels of PRC1/PRC2. Thus, parallel pathways explain the differential requirements for PRC1 and PRC2 and provide robust silencing of lineage-specific genes.
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Affiliation(s)
- J. A. Zepeda-Martinez
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - C. Pribitzer
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - J. Wang
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - D. Bsteh
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
- Department of Biochemistry and Molecular Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - S. Golumbeanu
- Department of Biochemistry and Molecular Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Q. Zhao
- Department of Biochemistry and Molecular Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - T. R. Burkard
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - B. Reichholf
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - S. K. Rhie
- Department of Biochemistry and Molecular Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - J. Jude
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - H. F. Moussa
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - J. Zuber
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - O. Bell
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria
- Department of Biochemistry and Molecular Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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RYBP/YAF2-PRC1 complexes and histone H1-dependent chromatin compaction mediate propagation of H2AK119ub1 during cell division. Nat Cell Biol 2020; 22:439-452. [PMID: 32203418 DOI: 10.1038/s41556-020-0484-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 02/14/2020] [Indexed: 01/12/2023]
Abstract
Stable propagation of epigenetic information is important for maintaining cell identity in multicellular organisms. However, it remains largely unknown how mono-ubiquitinated histone H2A on lysine 119 (H2AK119ub1) is established and stably propagated during cell division. In this study, we found that the proteins RYBP and YAF2 each specifically bind H2AK119ub1 to recruit the RYBP-PRC1 or YAF2-PRC1 complex to catalyse the ubiquitination of H2A on neighbouring nucleosomes through a positive-feedback model. Additionally, we demonstrated that histone H1-compacted chromatin enhances the distal propagation of H2AK119ub1, thereby reinforcing the inheritance of H2AK119ub1 during cell division. Moreover, we showed that either disruption of RYBP/YAF2-PRC1 activity or impairment of histone H1-dependent chromatin compaction resulted in a significant defect of the maintenance of H2AK119ub1. Therefore, our results suggest that histone H1-dependent chromatin compaction plays a critical role in the stable propagation of H2AK119ub1 by RYBP/YAF2-PRC1 during cell division.
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130
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Zhang X, Murray B, Mo G, Shern JF. The Role of Polycomb Repressive Complex in Malignant Peripheral Nerve Sheath Tumor. Genes (Basel) 2020; 11:genes11030287. [PMID: 32182803 PMCID: PMC7140867 DOI: 10.3390/genes11030287] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/24/2020] [Accepted: 03/02/2020] [Indexed: 12/24/2022] Open
Abstract
Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas that can arise most frequently in patients with neurofibromatosis type 1 (NF1). Despite an increasing understanding of the molecular mechanisms that underlie these tumors, there remains limited therapeutic options for this aggressive disease. One potentially critical finding is that a significant proportion of MPNSTs exhibit recurrent mutations in the genes EED or SUZ12, which are key components of the polycomb repressive complex 2 (PRC2). Tumors harboring these genetic lesions lose the marker of transcriptional repression, trimethylation of lysine residue 27 on histone H3 (H3K27me3) and have dysregulated oncogenic signaling. Given the recurrence of PRC2 alterations, intensive research efforts are now underway with a focus on detailing the epigenetic and transcriptomic consequences of PRC2 loss as well as development of novel therapeutic strategies for targeting these lesions. In this review article, we will summarize the recent findings of PRC2 in MPNST tumorigenesis, including highlighting the functions of PRC2 in normal Schwann cell development and nerve injury repair, as well as provide commentary on the potential therapeutic vulnerabilities of a PRC2 deficient tumor cell.
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Affiliation(s)
- Xiyuan Zhang
- Pediatric Oncology Branch, Tumor Evolution and Genomics Section, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (X.Z.); (B.M.); (G.M.)
| | - Béga Murray
- Pediatric Oncology Branch, Tumor Evolution and Genomics Section, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (X.Z.); (B.M.); (G.M.)
- The Patrick G Johnston Centre for Cancer Research, Queen’s University Belfast, 97 Lisburn road, Belfast BT9 7AE, UK
| | - George Mo
- Pediatric Oncology Branch, Tumor Evolution and Genomics Section, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (X.Z.); (B.M.); (G.M.)
- SUNY Downstate Health Sciences University, Brooklyn, NY 11203, USA
| | - Jack F. Shern
- Pediatric Oncology Branch, Tumor Evolution and Genomics Section, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (X.Z.); (B.M.); (G.M.)
- Correspondence:
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131
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Blackledge NP, Fursova NA, Kelley JR, Huseyin MK, Feldmann A, Klose RJ. PRC1 Catalytic Activity Is Central to Polycomb System Function. Mol Cell 2020; 77:857-874.e9. [PMID: 31883950 PMCID: PMC7033600 DOI: 10.1016/j.molcel.2019.12.001] [Citation(s) in RCA: 156] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/21/2019] [Accepted: 12/02/2019] [Indexed: 01/01/2023]
Abstract
The Polycomb repressive system is an essential chromatin-based regulator of gene expression. Despite being extensively studied, how the Polycomb system selects its target genes is poorly understood, and whether its histone-modifying activities are required for transcriptional repression remains controversial. Here, we directly test the requirement for PRC1 catalytic activity in Polycomb system function. To achieve this, we develop a conditional mutation system in embryonic stem cells that completely removes PRC1 catalytic activity. Using this system, we demonstrate that catalysis by PRC1 drives Polycomb chromatin domain formation and long-range chromatin interactions. Furthermore, we show that variant PRC1 complexes with DNA-binding activities occupy target sites independently of PRC1 catalytic activity, providing a putative mechanism for Polycomb target site selection. Finally, we discover that Polycomb-mediated gene repression requires PRC1 catalytic activity. Together these discoveries provide compelling evidence that PRC1 catalysis is central to Polycomb system function and gene regulation.
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Affiliation(s)
- Neil P Blackledge
- Department of Biochemistry, University of Oxford, South Parks Rd., Oxford OX1 3QU, UK
| | - Nadezda A Fursova
- Department of Biochemistry, University of Oxford, South Parks Rd., Oxford OX1 3QU, UK
| | - Jessica R Kelley
- Department of Biochemistry, University of Oxford, South Parks Rd., Oxford OX1 3QU, UK
| | - Miles K Huseyin
- Department of Biochemistry, University of Oxford, South Parks Rd., Oxford OX1 3QU, UK
| | - Angelika Feldmann
- Department of Biochemistry, University of Oxford, South Parks Rd., Oxford OX1 3QU, UK
| | - Robert J Klose
- Department of Biochemistry, University of Oxford, South Parks Rd., Oxford OX1 3QU, UK.
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132
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Healy E, Bracken AP. If You Like It Then You Shoulda Put Two "RINGs" on It: Delineating the Roles of vPRC1 and cPRC1. Mol Cell 2020; 77:685-687. [PMID: 32084351 DOI: 10.1016/j.molcel.2020.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
To delineate the roles of variant (vPRC1) and canonical (cPRC1) Polycomb repressive complex 1, Blackledge et al. (2020) and Tamburri et al. (2020) elegantly disrupt RING1A/B catalytic activity without affecting stability of either complex and then explore the precise contribution of vPRC1-mediated H2AK119ub1 to Polycomb-mediated gene repression.
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Affiliation(s)
- Evan Healy
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Adrian P Bracken
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.
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133
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134
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Johansen S, Gjerstorff MF. Interaction between Polycomb and SSX Proteins in Pericentromeric Heterochromatin Function and Its Implication in Cancer. Cells 2020; 9:cells9010226. [PMID: 31963307 PMCID: PMC7016822 DOI: 10.3390/cells9010226] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 01/10/2023] Open
Abstract
The stability of pericentromeric heterochromatin is maintained by repressive epigenetic control mechanisms, and failure to maintain this stability may cause severe diseases such as immune deficiency and cancer. Thus, deeper insight into the epigenetic regulation and deregulation of pericentromeric heterochromatin is of high priority. We and others have recently demonstrated that pericentromeric heterochromatin domains are often epigenetically reprogrammed by Polycomb proteins in premalignant and malignant cells to form large subnuclear structures known as Polycomb bodies. This may affect the regulation and stability of pericentromeric heterochromatin domains and/or the distribution of Polycomb factors to support tumorigeneses. Importantly, Polycomb bodies in cancer cells may be targeted by the cancer/testis-related SSX proteins to cause derepression and genomic instability of pericentromeric heterochromatin. This review will discuss the interplay between SSX and Polycomb factors in the repression and stability of pericentromeric heterochromatin and its possible implications for tumor biology.
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Affiliation(s)
- Simone Johansen
- Department of Cancer and Inflammation Research, Institute for Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark;
| | - Morten Frier Gjerstorff
- Department of Cancer and Inflammation Research, Institute for Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark;
- Department of Oncology, Odense University Hospital, 5000 Odense, Denmark
- Academy of Geriatric Cancer Research (AgeCare), Odense University Hospital, 5000 Odense, Denmark
- Correspondence: ; Tel.: +45-21261563
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135
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Flamier A, Abdouh M, Hamam R, Barabino A, Patel N, Gao A, Hanna R, Bernier G. Off-target effect of the BMI1 inhibitor PTC596 drives epithelial-mesenchymal transition in glioblastoma multiforme. NPJ Precis Oncol 2020; 4:1. [PMID: 31934644 PMCID: PMC6944693 DOI: 10.1038/s41698-019-0106-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 10/25/2019] [Indexed: 01/09/2023] Open
Abstract
Glioblastoma multiforme (GBM) is an incurable primary brain tumor containing a sub-population of cancer stem cells (CSCs). Polycomb Repressive Complex (PRC) proteins BMI1 and EZH2 are enriched in CSCs, promoting clonogenic growth and resistance to genotoxic therapies. We report here that when used at appropriate concentrations, pharmaceutical inhibitors of BMI1 could efficiently prevent GBM colony growth and CSC self-renewal in vitro and significantly extend lifespan in terminally ill tumor-bearing mice. Notably, molecular analyses revealed that the commonly used PTC596 molecule targeted both BMI1 and EZH2, possibly providing beneficial therapeutic effects in some contexts. On the other hand, treatment with PTC596 resulted in instant reactivation of EZH2 target genes and induction of a molecular program of epithelial–mesenchymal transition (EMT), possibly explaining the modified phenotype of some PTC596-treated tumors. Treatment with a related but more specific BMI1 inhibitor resulted in tumor regression and maintenance of cell identity. We conclude that inhibition of BMI1 alone is efficient at inducing GBM regression, and that dual inhibition of BMI1 and EZH2 using PTC596 may be also beneficial but only in specific contexts.
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Affiliation(s)
- Anthony Flamier
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada.,3Present Address: Whitehead Institute of Biomedical Research, 455 Main Street, Cambridge, 02142 MA USA
| | - Mohamed Abdouh
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada
| | - Rimi Hamam
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada
| | - Andrea Barabino
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada
| | - Niraj Patel
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada
| | - Andy Gao
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada
| | - Roy Hanna
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada
| | - Gilbert Bernier
- 1Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. l'Assomption, Montréal, H1T 2M4 Canada.,2Department of Neurosciences, University of Montreal, Montreal, Canada
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136
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Hugues A, Jacobs CS, Roudier F. Mitotic Inheritance of PRC2-Mediated Silencing: Mechanistic Insights and Developmental Perspectives. FRONTIERS IN PLANT SCIENCE 2020; 11:262. [PMID: 32211012 PMCID: PMC7075419 DOI: 10.3389/fpls.2020.00262] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 02/19/2020] [Indexed: 05/20/2023]
Abstract
Maintenance of gene repression by Polycomb Repressive Complex 2 (PRC2) that catalyzes the trimethylation of histone H3 at lysine 27 (H3K27me3) is integral to the orchestration of developmental programs in most multicellular eukaryotes. Faithful inheritance of H3K27me3 patterns across replication ensures the stability of PRC2-mediated transcriptional silencing over cell generations, thereby safeguarding cellular identities. In this review, we discuss the molecular and mechanistic principles that underlie H3K27me3 restoration after the passage of the replication fork, considering recent advances in different model systems. In particular, we aim at emphasizing parallels and differences between plants and other organisms, focusing on the recycling of parental histones and the replenishment of H3K27me3 patterns post-replication thanks to the remarkable properties of the PRC2 complex. We then discuss the necessity for fine-tuning this genuine epigenetic memory system so as to allow for cell fate and developmental transitions. We highlight recent insights showing that genome-wide destabilization of the H3K27me3 landscape during chromatin replication participates in achieving this flexible stability and provides a window of opportunity for subtle transcriptional reprogramming.
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Affiliation(s)
- Alice Hugues
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Université de Lyon, Lyon, France
- Master de Biologie, École Normale Supérieure de Lyon, Université Claude Bernard Lyon I, Université de Lyon, Lyon, France
| | - Chean Sern Jacobs
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Université de Lyon, Lyon, France
| | - François Roudier
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Université de Lyon, Lyon, France
- *Correspondence: François Roudier,
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137
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Tamburri S, Lavarone E, Fernández-Pérez D, Conway E, Zanotti M, Manganaro D, Pasini D. Histone H2AK119 Mono-Ubiquitination Is Essential for Polycomb-Mediated Transcriptional Repression. Mol Cell 2019; 77:840-856.e5. [PMID: 31883952 PMCID: PMC7033561 DOI: 10.1016/j.molcel.2019.11.021] [Citation(s) in RCA: 198] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 10/18/2019] [Accepted: 11/26/2019] [Indexed: 12/21/2022]
Abstract
Polycomb group proteins (PcGs) maintain transcriptional repression to preserve cellular identity in two distinct repressive complexes, PRC1 and PRC2, that modify histones by depositing H2AK119ub1 and H3K27me3, respectively. PRC1 and PRC2 exist in different variants and show a complex regulatory cross-talk. However, the contribution that H2AK119ub1 plays in mediating PcG repressive functions remains largely controversial. Using a fully catalytic inactive RING1B mutant, we demonstrated that H2AK119ub1 deposition is essential to maintain PcG-target gene repression in embryonic stem cells (ESCs). Loss of H2AK119ub1 induced a rapid displacement of PRC2 activity and a loss of H3K27me3 deposition. This preferentially affected PRC2.2 variant with respect to PRC2.1, destabilizing canonical PRC1 activity. Finally, we found that variant PRC1 forms can sense H2AK119ub1 deposition, which contributes to their stabilization specifically at sites where this modification is highly enriched. Overall, our data place H2AK119ub1 deposition as a central hub that mounts PcG repressive machineries to preserve cell transcriptional identity. Catalytic inactive RING1B I53S leads to complete loss of H2AK119ub1 deposition H2AK119ub1 is essential for the transcriptional repression of all RING1A/B targets H2AK119ub1 stabilizes cPRC1 and PRC2 activities, promoting H3K27me3 deposition Chromatin binding of variant PRC2.2 is preferentially impaired by loss of H2AK119ub1
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Affiliation(s)
- Simone Tamburri
- Department of Experimental Oncology, IEO European Institute of Oncology IRCCS, Via Adamello 16, 20139 Milan, Italy
| | - Elisa Lavarone
- Department of Experimental Oncology, IEO European Institute of Oncology IRCCS, Via Adamello 16, 20139 Milan, Italy
| | - Daniel Fernández-Pérez
- Department of Experimental Oncology, IEO European Institute of Oncology IRCCS, Via Adamello 16, 20139 Milan, Italy; Department of Health Sciences, University of Milan, Via A. di Rudinì 8, 20142 Milan, Italy
| | - Eric Conway
- Department of Experimental Oncology, IEO European Institute of Oncology IRCCS, Via Adamello 16, 20139 Milan, Italy
| | - Marika Zanotti
- Department of Experimental Oncology, IEO European Institute of Oncology IRCCS, Via Adamello 16, 20139 Milan, Italy
| | - Daria Manganaro
- Department of Experimental Oncology, IEO European Institute of Oncology IRCCS, Via Adamello 16, 20139 Milan, Italy
| | - Diego Pasini
- Department of Experimental Oncology, IEO European Institute of Oncology IRCCS, Via Adamello 16, 20139 Milan, Italy; Department of Health Sciences, University of Milan, Via A. di Rudinì 8, 20142 Milan, Italy.
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138
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Chammas P, Mocavini I, Di Croce L. Engaging chromatin: PRC2 structure meets function. Br J Cancer 2019; 122:315-328. [PMID: 31708574 PMCID: PMC7000746 DOI: 10.1038/s41416-019-0615-2] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/24/2019] [Indexed: 01/01/2023] Open
Abstract
Polycomb repressive complex 2 (PRC2) is a key epigenetic multiprotein complex involved in the regulation of gene expression in metazoans. PRC2 is formed by a tetrameric core that endows the complex with histone methyltransferase activity, allowing it to mono-, di- and tri-methylate histone H3 on lysine 27 (H3K27me1/2/3); H3K27me3 is a hallmark of facultative heterochromatin. The core complex of PRC2 is bound by several associated factors that are responsible for modulating its targeting specificity and enzymatic activity. Depletion and/or mutation of the subunits of this complex can result in severe developmental defects, or even lethality. Furthermore, mutations of these proteins in somatic cells can be drivers of tumorigenesis, by altering the transcriptional regulation of key tumour suppressors or oncogenes. In this review, we present the latest results from structural studies that have characterised PRC2 composition and function. We compare this information with data and literature for both gain-of function and loss-of-function missense mutations in cancers to provide an overview of the impact of these mutations on PRC2 activity.
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Affiliation(s)
- Paul Chammas
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Dr. Aiguader 88, Barcelona, 08003, Spain
| | - Ivano Mocavini
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Dr. Aiguader 88, Barcelona, 08003, Spain
| | - Luciano Di Croce
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Dr. Aiguader 88, Barcelona, 08003, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain. .,ICREA, Pg Lluis Companys 23, Barcelona, 08010, Spain.
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139
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C10ORF12 modulates PRC2 histone methyltransferase activity and H3K27me3 levels. Acta Pharmacol Sin 2019; 40:1457-1465. [PMID: 31186533 DOI: 10.1038/s41401-019-0247-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 05/05/2019] [Indexed: 01/03/2023] Open
Abstract
The polycomb repressive complex 2 (PRC2) catalyzes the methylation of histone H3 on lysine 27 (H3K27) to generate trimethyl-H3K27 (H3K27me3) marks, thereby leading to a repressive chromatin state that inhibits gene expression. C10ORF12 was recently identified as a novel PRC2 interactor. Here, we show that C10ORF12 specifically interacts with PRC2 through its middle region (positions 619-718). C10ORF12 significantly enhances the histone methyltransferase activity of PRC2 in vitro and dramatically increases the total H3K27me3 levels in HeLa cells. C10ORF12 also antagonizes Jarid2, which is an auxiliary factor of the PRC2.2 subcomplex, to promote increased H3K27me3 levels in HeLa cells. Moreover, C10ORF12 alters the substrate preference of PRC2. These results indicate that C10ORF12 functions as a positive regulator of PRC2 and facilitates PRC2-mediated H3K27me3 modification of chromatin. These findings provide new insight into the roles of C10ORF12 in regulating the activity of the PRC2 complex.
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140
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Abstract
A lysine-to-methionine mutation at lysine 27 of histone 3 (H3K27M) has been shown to promote oncogenesis in a subset of pediatric gliomas. While there is evidence that this "oncohistone" mutation acts by inhibiting the histone methyltransferase PRC2, the details of this proposed mechanism nevertheless continue to be debated. Recent evidence suggests that PRC2 must simultaneously bind both H3K27M and H3K27me3 to experience competitive inhibition of its methyltransferase activity. In this work, we used PRC2 inhibitor treatments in a transgenic H3K27M cell line to validate this dependence in a cellular context. We further used designer chromatin inhibitors to probe the geometric constraints of PRC2 engagement of H3K27M and H3K27me3 in a biochemical setting. We found that PRC2 binds to a bivalent inhibitor unit consisting of an H3K27M and an H3K27me3 nucleosome and exhibits a distance dependence in its affinity for such an inhibitor, which favors closer proximity of the 2 nucleosomes within a chromatin array. Together, our data precisely delineate fundamental aspects of the H3K27M inhibitor and support a model wherein PRC2 becomes trapped at H3K27M-H3K27me3 boundaries.
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141
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Oya E, Nakagawa R, Yoshimura Y, Tanaka M, Nishibuchi G, Machida S, Shirai A, Ekwall K, Kurumizaka H, Tagami H, Nakayama J. H3K14 ubiquitylation promotes H3K9 methylation for heterochromatin assembly. EMBO Rep 2019; 20:e48111. [PMID: 31468675 PMCID: PMC6776926 DOI: 10.15252/embr.201948111] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 08/07/2019] [Accepted: 08/09/2019] [Indexed: 12/28/2022] Open
Abstract
The methylation of histone H3 at lysine 9 (H3K9me), performed by the methyltransferase Clr4/SUV39H, is a key event in heterochromatin assembly. In fission yeast, Clr4, together with the ubiquitin E3 ligase Cul4, forms the Clr4 methyltransferase complex (CLRC), whose physiological targets and biological role are currently unclear. Here, we show that CLRC-dependent H3 ubiquitylation regulates Clr4's methyltransferase activity. Affinity-purified CLRC ubiquitylates histone H3, and mass spectrometric and mutation analyses reveal that H3 lysine 14 (H3K14) is the preferred target of the complex. Chromatin immunoprecipitation analysis shows that H3K14 ubiquitylation (H3K14ub) is closely associated with H3K9me-enriched chromatin. Notably, the CLRC-mediated H3 ubiquitylation promotes H3K9me by Clr4, suggesting that H3 ubiquitylation is intimately linked to the establishment and/or maintenance of H3K9me. These findings demonstrate a cross-talk mechanism between histone ubiquitylation and methylation that is involved in heterochromatin assembly.
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Affiliation(s)
- Eriko Oya
- Graduate School of Natural SciencesNagoya City UniversityNagoyaJapan
- Department of Biosciences and NutritionKarolinska InstitutetHuddingeSweden
- Present address:
Faculty of Science and EngineeringChuo UniversityBunkyo‐ku, TokyoJapan
| | - Reiko Nakagawa
- Laboratory for PhyloinformaticsRIKEN Center for Biosystems Dynamics ResearchKobeJapan
| | - Yuriko Yoshimura
- Division of Chromatin RegulationNational Institute for Basic BiologyOkazakiJapan
| | - Mayo Tanaka
- Division of Chromatin RegulationNational Institute for Basic BiologyOkazakiJapan
| | - Gohei Nishibuchi
- Graduate School of Natural SciencesNagoya City UniversityNagoyaJapan
- Present address:
Graduate School of ScienceOsaka UniversityToyonakaJapan
| | - Shinichi Machida
- Laboratory of Structural BiologyGraduate School of Advanced Science and EngineeringWaseda UniversityShinjuku‐ku, TokyoJapan
- Present address:
Institute of Human GeneticsCNRS UMR 9002MontpellierFrance
| | | | - Karl Ekwall
- Department of Biosciences and NutritionKarolinska InstitutetHuddingeSweden
| | - Hitoshi Kurumizaka
- Laboratory of Structural BiologyGraduate School of Advanced Science and EngineeringWaseda UniversityShinjuku‐ku, TokyoJapan
- Laboratory of Chromatin Structure and FunctionInstitute for Quantitative BiosciencesThe University of TokyoBunkyo‐ku, TokyoJapan
| | - Hideaki Tagami
- Graduate School of Natural SciencesNagoya City UniversityNagoyaJapan
| | - Jun‐ichi Nakayama
- Graduate School of Natural SciencesNagoya City UniversityNagoyaJapan
- Division of Chromatin RegulationNational Institute for Basic BiologyOkazakiJapan
- Department of Basic BiologySchool of Life ScienceThe Graduate University for Advanced Studies (SOKENDAI)OkazakiJapan
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142
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Beltran M, Tavares M, Justin N, Khandelwal G, Ambrose J, Foster BM, Worlock KB, Tvardovskiy A, Kunzelmann S, Herrero J, Bartke T, Gamblin SJ, Wilson JR, Jenner RG. G-tract RNA removes Polycomb repressive complex 2 from genes. Nat Struct Mol Biol 2019; 26:899-909. [PMID: 31548724 PMCID: PMC6778522 DOI: 10.1038/s41594-019-0293-z] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 08/05/2019] [Indexed: 12/15/2022]
Abstract
Polycomb Repressive Complex 2 (PRC2) maintains repression of cell type-specific genes but also associates with genes ectopically in cancer. While it is currently unknown how PRC2 is removed from genes, such knowledge would be useful for the targeted reversal of deleterious PRC2 recruitment events. Here, we show that G-tract RNA specifically removes PRC2 from genes in human and mouse cells. PRC2 preferentially binds G-tracts within nascent pre-mRNAs, especially within predicted G-quadruplex structures. G-quadruplex RNA evicts the PRC2 catalytic core from the substrate nucleosome. PRC2 transfers from chromatin to RNA upon gene activation and chromatin-associated G-tract RNA removes PRC2, leading to H3K27me3 depletion from genes. Targeting G-tract RNA to the tumor suppressor gene CDKN2A in malignant rhabdoid tumor cells reactivates the gene and induces senescence. These data support a model in which pre-mRNA evicts PRC2 during gene activation and provides the means to selectively remove PRC2 from specific genes.
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Affiliation(s)
- Manuel Beltran
- UCL Cancer Institute and Cancer Research UK UCL Centre, University College London (UCL), London, UK
| | - Manuel Tavares
- UCL Cancer Institute and Cancer Research UK UCL Centre, University College London (UCL), London, UK
| | | | - Garima Khandelwal
- UCL Cancer Institute and Cancer Research UK UCL Centre, University College London (UCL), London, UK
| | - John Ambrose
- UCL Cancer Institute and Cancer Research UK UCL Centre, University College London (UCL), London, UK.,Genomics England, London, UK
| | - Benjamin M Foster
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Kaylee B Worlock
- UCL Cancer Institute and Cancer Research UK UCL Centre, University College London (UCL), London, UK
| | - Andrey Tvardovskiy
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
| | | | - Javier Herrero
- UCL Cancer Institute and Cancer Research UK UCL Centre, University College London (UCL), London, UK
| | - Till Bartke
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
| | | | | | - Richard G Jenner
- UCL Cancer Institute and Cancer Research UK UCL Centre, University College London (UCL), London, UK.
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143
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Ge EJ, Jani KS, Diehl KL, Müller MM, Muir TW. Nucleation and Propagation of Heterochromatin by the Histone Methyltransferase PRC2: Geometric Constraints and Impact of the Regulatory Subunit JARID2. J Am Chem Soc 2019; 141:15029-15039. [PMID: 31479253 DOI: 10.1021/jacs.9b02321] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Polycomb Repressive Complex 2 (PRC2) catalyzes mono-, di-, and trimethylation of lysine 27 on histone H3 (H3K27me1-3) to control expression of genes important for differentiation and maintenance of cell identity. PRC2 activity is regulated by a number of different inputs, including allosteric activation by its product, H3K27me3. This positive feedback loop is thought to be important for the establishment of large domains of condensed heterochromatin. In addition to other chromatin modifications, ancillary subunits of PRC2, foremost JARID2, affect the rate of H3K27 methylation. Many gaps remain in our understanding of how PRC2 integrates these various signals to determine where and when to deposit H3K27 methyl marks. In this study, we utilize designer chromatin substrates to demonstrate that propagation of H3K27 methylation by the PRC2 core complex has geometrically defined preferences that are overridden by the presence of JARID2. Our studies also show that phosphorylation of JARID2 can partially regulate its ability to stimulate PRC2 activity. Collectively, these biochemical insights further our understanding of the mechanisms that govern PRC2 activity, and highlight a role for JARID2 in de novo deposition of H3K27me3-containing repressive domains.
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Affiliation(s)
- Eva J Ge
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Krupa S Jani
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Katharine L Diehl
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Manuel M Müller
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Tom W Muir
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
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144
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Healy E, Mucha M, Glancy E, Fitzpatrick DJ, Conway E, Neikes HK, Monger C, Van Mierlo G, Baltissen MP, Koseki Y, Vermeulen M, Koseki H, Bracken AP. PRC2.1 and PRC2.2 Synergize to Coordinate H3K27 Trimethylation. Mol Cell 2019; 76:437-452.e6. [PMID: 31521505 DOI: 10.1016/j.molcel.2019.08.012] [Citation(s) in RCA: 114] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/28/2019] [Accepted: 08/12/2019] [Indexed: 12/12/2022]
Abstract
Polycomb repressive complex 2 (PRC2) is composed of EED, SUZ12, and EZH1/2 and mediates mono-, di-, and trimethylation of histone H3 at lysine 27. At least two independent subcomplexes exist, defined by their specific accessory proteins: PRC2.1 (PCL1-3, EPOP, and PALI1/2) and PRC2.2 (AEBP2 and JARID2). We show that PRC2.1 and PRC2.2 share the majority of target genes in mouse embryonic stem cells. The loss of PCL1-3 is sufficient to evict PRC2.1 from Polycomb target genes but only leads to a partial reduction of PRC2.2 and H3K27me3. Conversely, disruption of PRC2.2 function through the loss of either JARID2 or RING1A/B is insufficient to completely disrupt targeting of SUZ12 by PCLs. Instead, the combined loss of both PRC2.1 and PRC2.2 is required, leading to the global mislocalization of SUZ12. This supports a model in which the specific accessory proteins within PRC2.1 and PRC2.2 cooperate to direct H3K27me3 via both synergistic and independent mechanisms.
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Affiliation(s)
- Evan Healy
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Marlena Mucha
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Eleanor Glancy
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | | | - Eric Conway
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Hannah K Neikes
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Craig Monger
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Guido Van Mierlo
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Marijke P Baltissen
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Yoko Koseki
- Laboratory for Developmental Genetics, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan
| | - Michiel Vermeulen
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Haruhiko Koseki
- Laboratory for Developmental Genetics, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan
| | - Adrian P Bracken
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.
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145
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Densham RM, Morris JR. Moving Mountains-The BRCA1 Promotion of DNA Resection. Front Mol Biosci 2019; 6:79. [PMID: 31552267 PMCID: PMC6733915 DOI: 10.3389/fmolb.2019.00079] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 08/20/2019] [Indexed: 12/26/2022] Open
Abstract
DNA double-strand breaks (DSBs) occur in our cells in the context of chromatin. This type of lesion is toxic, entirely preventing genome continuity and causing cell death or terminal arrest. Several repair mechanisms can act on DNA surrounding a DSB, only some of which carry a low risk of mutation, so that which repair process is utilized is critical to the stability of genetic material of cells. A key component of repair outcome is the degree of DNA resection directed to either side of the break site. This in turn determines the subsequent forms of repair in which DNA homology plays a part. Here we will focus on chromatin and chromatin-bound complexes which constitute the "mountains" that block resection, with a particular focus on how the breast and ovarian cancer predisposition protein-1 (BRCA1) contributes to repair outcomes through overcoming these blocks.
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Affiliation(s)
| | - Joanna R. Morris
- Birmingham Centre for Genome Biology, Institute of Cancer and Genomic Sciences, Medical and Dental Schools, University of Birmingham, Birmingham, United Kingdom
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146
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EZHIP constrains Polycomb Repressive Complex 2 activity in germ cells. Nat Commun 2019; 10:3858. [PMID: 31451685 PMCID: PMC6710278 DOI: 10.1038/s41467-019-11800-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 08/06/2019] [Indexed: 12/18/2022] Open
Abstract
The Polycomb group of proteins is required for the proper orchestration of gene expression due to its role in maintaining transcriptional silencing. It is composed of several chromatin modifying complexes, including Polycomb Repressive Complex 2 (PRC2), which deposits H3K27me2/3. Here, we report the identification of a cofactor of PRC2, EZHIP (EZH1/2 Inhibitory Protein), expressed predominantly in the gonads. EZHIP limits the enzymatic activity of PRC2 and lessens the interaction between the core complex and its accessory subunits, but does not interfere with PRC2 recruitment to chromatin. Deletion of Ezhip in mice leads to a global increase in H3K27me2/3 deposition both during spermatogenesis and at late stages of oocyte maturation. This does not affect the initial number of follicles but is associated with a reduction of follicles in aging. Our results suggest that mature oocytes Ezhip-/- might not be fully functional and indicate that fertility is strongly impaired in Ezhip-/- females. Altogether, our study uncovers EZHIP as a regulator of chromatin landscape in gametes.
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147
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Lamb KN, Bsteh D, Dishman SN, Moussa HF, Fan H, Stuckey JI, Norris JL, Cholensky SH, Li D, Wang J, Sagum C, Stanton BZ, Bedford MT, Pearce KH, Kenakin TP, Kireev DB, Wang GG, James LI, Bell O, Frye SV. Discovery and Characterization of a Cellular Potent Positive Allosteric Modulator of the Polycomb Repressive Complex 1 Chromodomain, CBX7. Cell Chem Biol 2019; 26:1365-1379.e22. [PMID: 31422906 DOI: 10.1016/j.chembiol.2019.07.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 06/08/2019] [Accepted: 07/25/2019] [Indexed: 12/13/2022]
Abstract
Polycomb-directed repression of gene expression is frequently misregulated in human diseases. A quantitative and target-specific cellular assay was utilized to discover the first potent positive allosteric modulator (PAM) peptidomimetic, UNC4976, of nucleic acid binding by CBX7, a chromodomain methyl-lysine reader of Polycomb repressive complex 1. The PAM activity of UNC4976 resulted in enhanced efficacy across three orthogonal cellular assays by simultaneously antagonizing H3K27me3-specific recruitment of CBX7 to target genes while increasing non-specific binding to DNA and RNA. PAM activity thereby reequilibrates PRC1 away from H3K27me3 target regions. Together, our discovery and characterization of UNC4976 not only revealed the most cellularly potent PRC1-specific chemical probe to date, but also uncovers a potential mechanism of Polycomb regulation with implications for non-histone lysine methylated interaction partners.
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Affiliation(s)
- Kelsey N Lamb
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Daniel Bsteh
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria; Department of Biochemistry and Molecular Medicine and Norris Comprehensive Cancer Center, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, USA
| | - Sarah N Dishman
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Hagar F Moussa
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Huitao Fan
- Lineberger Comprehensive Cancer Center, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Biochemistry and Biophysics, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jacob I Stuckey
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jacqueline L Norris
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Stephanie H Cholensky
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Dongxu Li
- Lineberger Comprehensive Cancer Center, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Biochemistry and Biophysics, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jingkui Wang
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Cari Sagum
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Smithville, TX 78957, USA
| | - Benjamin Z Stanton
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences NIH, Rockville, MD 20850, USA
| | - Mark T Bedford
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Smithville, TX 78957, USA
| | - Kenneth H Pearce
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Terry P Kenakin
- Department of Pharmacology, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Dmitri B Kireev
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Gang Greg Wang
- Lineberger Comprehensive Cancer Center, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Biochemistry and Biophysics, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Lindsey I James
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Oliver Bell
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria; Department of Biochemistry and Molecular Medicine and Norris Comprehensive Cancer Center, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, USA.
| | - Stephen V Frye
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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148
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Schertzer MD, Braceros KCA, Starmer J, Cherney RE, Lee DM, Salazar G, Justice M, Bischoff SR, Cowley DO, Ariel P, Zylka MJ, Dowen JM, Magnuson T, Calabrese JM. lncRNA-Induced Spread of Polycomb Controlled by Genome Architecture, RNA Abundance, and CpG Island DNA. Mol Cell 2019; 75:523-537.e10. [PMID: 31256989 PMCID: PMC6688959 DOI: 10.1016/j.molcel.2019.05.028] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 04/10/2019] [Accepted: 05/17/2019] [Indexed: 01/28/2023]
Abstract
Long noncoding RNAs (lncRNAs) cause Polycomb repressive complexes (PRCs) to spread over broad regions of the mammalian genome. We report that in mouse trophoblast stem cells, the Airn and Kcnq1ot1 lncRNAs induce PRC-dependent chromatin modifications over multi-megabase domains. Throughout the Airn-targeted domain, the extent of PRC-dependent modification correlated with intra-nuclear distance to the Airn locus, preexisting genome architecture, and the abundance of Airn itself. Specific CpG islands (CGIs) displayed characteristics indicating that they nucleate the spread of PRCs upon exposure to Airn. Chromatin environments surrounding Xist, Airn, and Kcnq1ot1 suggest common mechanisms of PRC engagement and spreading. Our data indicate that lncRNA potency can be tightly linked to lncRNA abundance and that within lncRNA-targeted domains, PRCs are recruited to CGIs via lncRNA-independent mechanisms. We propose that CGIs that autonomously recruit PRCs interact with lncRNAs and their associated proteins through three-dimensional space to nucleate the spread of PRCs in lncRNA-targeted domains.
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Affiliation(s)
- Megan D Schertzer
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Keean C A Braceros
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, USA; Curriculum in Mechanistic, Interdisciplinary Studies of Biological Systems, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Joshua Starmer
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Rachel E Cherney
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - David M Lee
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Gabriela Salazar
- Department of Cell Biology and Physiology and UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Megan Justice
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA; Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Steven R Bischoff
- Animal Models Core, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Dale O Cowley
- Animal Models Core, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Pablo Ariel
- Microscopy Services Laboratory and Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Mark J Zylka
- Department of Cell Biology and Physiology and UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Jill M Dowen
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA; Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Terry Magnuson
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - J Mauro Calabrese
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
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149
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Tsuboi M, Hirabayashi Y, Gotoh Y. Diverse gene regulatory mechanisms mediated by Polycomb group proteins during neural development. Curr Opin Neurobiol 2019; 59:164-173. [PMID: 31398486 DOI: 10.1016/j.conb.2019.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 07/07/2019] [Indexed: 12/26/2022]
Abstract
While all the developmental genes are temporarily repressed for future activation in the pluripotent stem cells, non-neural genes become persistently repressed in the course of commitment to the neuronal lineage. Although Polycomb group proteins (PcG) are key factors for both temporary and persistent repression of the developmental genes, how the same group of proteins can differentially repress target genes remains unclarified. The identification of a variety of PcG complexes and activities sheds light on these issues. In this review, based on the recent findings including those with the use of interactome and Chromosome Conformation Capture (3C)-type analyses, we summarize the molecular mechanisms of PcG-mediated gene regulation and discuss how PcG regulates cell fate specification during neural development.
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Affiliation(s)
- Masafumi Tsuboi
- Graduate School of Engineering, The University of Tokyo, Tokyo 113-0033, Japan.
| | - Yusuke Hirabayashi
- Graduate School of Engineering, The University of Tokyo, Tokyo 113-0033, Japan
| | - Yukiko Gotoh
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo, Tokyo 113-0033, Japan
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150
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Abstract
As the process that silences gene expression ensues during development, the stage is set for the activity of Polycomb-repressive complex 2 (PRC2) to maintain these repressed gene profiles. PRC2 catalyzes a specific histone posttranslational modification (hPTM) that fosters chromatin compaction. PRC2 also facilitates the inheritance of this hPTM through its self-contained "write and read" activities, key to preserving cellular identity during cell division. As these changes in gene expression occur without changes in DNA sequence and are inherited, the process is epigenetic in scope. Mutants of mammalian PRC2 or of its histone substrate contribute to the cancer process and other diseases, and research into these aberrant pathways is yielding viable candidates for therapeutic targeting. The effectiveness of PRC2 hinges on its being recruited to the proper chromatin sites; however, resolving the determinants to this process in the mammalian case was not straightforward and thus piqued the interest of many in the field. Here, we chronicle the latest advances toward exposing mammalian PRC2 and its high maintenance.
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Affiliation(s)
- Jia-Ray Yu
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - Chul-Hwan Lee
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - Ozgur Oksuz
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - James M Stafford
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - Danny Reinberg
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
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