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Hisanaga T, Romani F, Wu S, Kowar T, Wu Y, Lintermann R, Fridrich A, Cho CH, Chaumier T, Jamge B, Montgomery SA, Axelsson E, Akimcheva S, Dierschke T, Bowman JL, Fujiwara T, Hirooka S, Miyagishima SY, Dolan L, Tirichine L, Schubert D, Berger F. The Polycomb repressive complex 2 deposits H3K27me3 and represses transposable elements in a broad range of eukaryotes. Curr Biol 2023; 33:4367-4380.e9. [PMID: 37738971 DOI: 10.1016/j.cub.2023.08.073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 06/19/2023] [Accepted: 08/24/2023] [Indexed: 09/24/2023]
Abstract
The mobility of transposable elements (TEs) contributes to evolution of genomes. Their uncontrolled activity causes genomic instability; therefore, expression of TEs is silenced by host genomes. TEs are marked with DNA and H3K9 methylation, which are associated with silencing in flowering plants, animals, and fungi. However, in distantly related groups of eukaryotes, TEs are marked by H3K27me3 deposited by the Polycomb repressive complex 2 (PRC2), an epigenetic mark associated with gene silencing in flowering plants and animals. The direct silencing of TEs by PRC2 has so far only been shown in one species of ciliates. To test if PRC2 silences TEs in a broader range of eukaryotes, we generated mutants with reduced PRC2 activity and analyzed the role of PRC2 in extant species along the lineage of Archaeplastida and in the diatom P. tricornutum. In this diatom and the red alga C. merolae, a greater proportion of TEs than genes were repressed by PRC2, whereas a greater proportion of genes than TEs were repressed by PRC2 in bryophytes. In flowering plants, TEs contained potential cis-elements recognized by transcription factors and associated with neighbor genes as transcriptional units repressed by PRC2. Thus, silencing of TEs by PRC2 is observed not only in Archaeplastida but also in diatoms and ciliates, suggesting that PRC2 deposited H3K27me3 to silence TEs in the last common ancestor of eukaryotes. We hypothesize that during the evolution of Archaeplastida, TE fragments marked with H3K27me3 were selected to shape transcriptional regulation, controlling networks of genes regulated by PRC2.
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Affiliation(s)
- Tetsuya Hisanaga
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Facundo Romani
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK
| | - Shuangyang Wu
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Teresa Kowar
- Epigenetics of Plants, Institute of Biology, Freie Universität Berlin, 14195 Berlin, Germany
| | - Yue Wu
- Nantes Université, CNRS, US2B, UMR 6286, 44000 Nantes, France
| | - Ruth Lintermann
- Epigenetics of Plants, Institute of Biology, Freie Universität Berlin, 14195 Berlin, Germany
| | - Arie Fridrich
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Chung Hyun Cho
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria; Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, South Korea
| | | | - Bhagyshree Jamge
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria; Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, 1030 Vienna, Austria
| | - Sean A Montgomery
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria; Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, 1030 Vienna, Austria
| | - Elin Axelsson
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Svetlana Akimcheva
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Tom Dierschke
- School of Biological Sciences, Monash University, Melbourne, VIC 3800, Australia
| | - John L Bowman
- School of Biological Sciences, Monash University, Melbourne, VIC 3800, Australia; ARC Centre of Excellence for Plant Success in Nature and Agriculture, Monash University, Clayton, Melbourne, VIC 3800, Australia
| | - Takayuki Fujiwara
- Department of Gene Function and Phenomics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan; Department of Genetics, Graduate University for Advanced Studies, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Shunsuke Hirooka
- Department of Gene Function and Phenomics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan; Department of Genetics, Graduate University for Advanced Studies, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Shin-Ya Miyagishima
- Department of Gene Function and Phenomics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan; Department of Genetics, Graduate University for Advanced Studies, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Liam Dolan
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Leila Tirichine
- Nantes Université, CNRS, US2B, UMR 6286, 44000 Nantes, France
| | - Daniel Schubert
- Epigenetics of Plants, Institute of Biology, Freie Universität Berlin, 14195 Berlin, Germany.
| | - Frédéric Berger
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria.
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Chen Z, Seman M, Farhat A, Fyodorova Y, Biswas S, Levashkevich A, Freddolino PL, Biteen JS, Ragunathan K. Tracking live-cell single-molecule dynamics enables measurements of heterochromatinassociated protein-protein interactions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.08.531771. [PMID: 36945633 PMCID: PMC10028927 DOI: 10.1101/2023.03.08.531771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Visualizing and measuring molecular-scale interactions in living cells represents a major challenge, but recent advances in microscopy are bringing us closer to achieving this goal. Single-molecule super-resolution microscopy enables high-resolution and sensitive imaging of the positions and movement of molecules in living cells. HP1 proteins are important regulators of gene expression because they selectively bind and recognize H3K9 methylated (H3K9me) histones to form heterochromatin-associated protein complexes that silence gene expression. Here, we extended live-cell single-molecule tracking studies in fission yeast to determine how HP1 proteins interact with their binding partners in the nucleus. We measured how genetic perturbations that affect H3K9me alter the diffusive properties of HP1 proteins and each of their binding partners based on which we inferred their most likely interaction sites. Our results indicate that H3K9me promotes specific complex formation between HP1 proteins and their interactors in a spatially restricted manner, while attenuating their ability to form off-chromatin complexes. As opposed to being an inert platform or scaffold to direct HP1 binding, our studies propose a novel function for H3K9me as an active participant in enhancing HP1-associated complex formation in living cells.
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Affiliation(s)
- Ziyuan Chen
- Department of Biophysics, University of Michigan, Ann Arbor, MI 48104 USA
| | - Melissa Seman
- Department of Biology, Brandeis University, Waltham, MA 02451 USA
| | - Ali Farhat
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109 USA
| | | | - Saikat Biswas
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48104 USA
- Current address: Pacific Biosciences, Menlo Park, CA 94025, USA
| | | | - P. Lydia Freddolino
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48104 USA
| | - Julie S. Biteen
- Department of Biophysics, University of Michigan, Ann Arbor, MI 48104 USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48104 USA
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3
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Williams MR, Xiaokang Y, Hathaway NA, Kireev D. A simulation model of heterochromatin formation at submolecular detail. iScience 2022; 25:104590. [PMID: 35800764 PMCID: PMC9254115 DOI: 10.1016/j.isci.2022.104590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 11/16/2021] [Accepted: 06/08/2022] [Indexed: 11/15/2022] Open
Abstract
Heterochromatin is a physical state of the chromatin fiber that maintains gene repression during cell development. Although evidence exists on molecular mechanisms involved in heterochromatin formation, a detailed structural mechanism of heterochromatin formation needs a better understanding. We made use of a simple Monte Carlo simulation model with explicit representation of key molecular events to observe molecular self-organization leading to heterochromatin formation. Our simulations provide a structural interpretation of several important traits of the heterochromatinization process. In particular, this study provides a depiction of how small amounts of HP1 are able to induce a highly condensed chromatin state through HP1 dimerization and bridging of sequence-remote nucleosomes. It also elucidates structural roots of a yet poorly understood phenomenon of a nondeterministic nature of heterochromatin formation and subsequent gene repression. Experimental chromatin in vivo assay provides an unbiased estimate of time scale of repressive response to a heterochromatin-triggering event.
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Affiliation(s)
- Michael R. Williams
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
| | - Yan Xiaokang
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA
| | - Nathaniel A. Hathaway
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA
| | - Dmitri Kireev
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
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Ancona M, Brackley CA. Simulating the chromatin mediated phase separation of model proteins with multiple domains. Biophys J 2022; 121:2600-2612. [DOI: 10.1016/j.bpj.2022.05.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 04/28/2022] [Accepted: 05/24/2022] [Indexed: 11/28/2022] Open
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Mei L, Kedziora KM, Song EA, Purvis JE, Cook J. The consequences of differential origin licensing dynamics in distinct chromatin environments. Nucleic Acids Res 2022; 50:9601-9620. [PMID: 35079814 PMCID: PMC9508807 DOI: 10.1093/nar/gkac003] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/17/2021] [Accepted: 01/05/2022] [Indexed: 02/01/2023] Open
Abstract
Eukaryotic chromosomes contain regions of varying accessibility, yet DNA replication factors must access all regions. The first replication step is loading MCM complexes to license replication origins during the G1 cell cycle phase. It is not yet known how mammalian MCM complexes are adequately distributed to both accessible euchromatin regions and less accessible heterochromatin regions. To address this question, we combined time-lapse live-cell imaging with immunofluorescence imaging of single human cells to quantify the relative rates of MCM loading in euchromatin and heterochromatin throughout G1. We report here that MCM loading in euchromatin is faster than that in heterochromatin in early G1, but surprisingly, heterochromatin loading accelerates relative to euchromatin loading in middle and late G1. This differential acceleration allows both chromatin types to begin S phase with similar concentrations of loaded MCM. The different loading dynamics require ORCA-dependent differences in origin recognition complex distribution. A consequence of heterochromatin licensing dynamics is that cells experiencing a truncated G1 phase from premature cyclin E expression enter S phase with underlicensed heterochromatin, and DNA damage accumulates preferentially in heterochromatin in the subsequent S/G2 phase. Thus, G1 length is critical for sufficient MCM loading, particularly in heterochromatin, to ensure complete genome duplication and to maintain genome stability.
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Affiliation(s)
- Liu Mei
- Department of Biochemistry & Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Katarzyna M Kedziora
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Bioinformatics and Analytics Research Collaborative (BARC), University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Eun-Ah Song
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jeremy E Purvis
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jeanette Gowen Cook
- Department of Biochemistry & Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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6
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Shining Light on the Dark Side of the Genome. Cells 2022; 11:cells11030330. [PMID: 35159140 PMCID: PMC8834555 DOI: 10.3390/cells11030330] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/16/2022] [Accepted: 01/17/2022] [Indexed: 11/17/2022] Open
Abstract
Heterochromatin has historically been considered the dark side of the genome. In part, this reputation derives from its concentration near centromeres and telomeres, regions of the genome repressive to nuclear functions such as DNA replication and transcription. The repetitive nature of heterochromatic DNA has only added to its “darkness”, as sequencing of these DNA regions has been only recently achieved. Despite such obstacles, research on heterochromatin blossomed over the past decades. Success in this area benefitted from efforts of Sergio Pimpinelli and colleagues who made landmark discoveries and promoted the growth of an international community of researchers. They discovered complexities of heterochromatin, demonstrating that a key component, Heterochromatin Protein 1a (HP1a), uses multiple mechanisms to associate with chromosomes and has positive and negative effects on gene expression, depending on the chromosome context. In addition, they updated the work of Carl Waddington using molecular tools that revealed how environmental stress promotes genome change due to transposable element movement. Collectively, their research and that of many others in the field have shined a bright light on the dark side of the genome and helped reveal many mysteries of heterochromatin.
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Ulianov SV, Velichko A, Magnitov MD, Luzhin A, Golov AK, Ovsyannikova N, Kireev II, Gavrikov A, Mishin A, Garaev AK, Tyakht AV, Gavrilov A, Kantidze OL, Razin SV. Suppression of liquid-liquid phase separation by 1,6-hexanediol partially compromises the 3D genome organization in living cells. Nucleic Acids Res 2021; 49:10524-10541. [PMID: 33836078 PMCID: PMC8501969 DOI: 10.1093/nar/gkab249] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/22/2021] [Accepted: 03/25/2021] [Indexed: 12/12/2022] Open
Abstract
Liquid-liquid phase separation (LLPS) contributes to the spatial and functional segregation of molecular processes within the cell nucleus. However, the role played by LLPS in chromatin folding in living cells remains unclear. Here, using stochastic optical reconstruction microscopy (STORM) and Hi-C techniques, we studied the effects of 1,6-hexanediol (1,6-HD)-mediated LLPS disruption/modulation on higher-order chromatin organization in living cells. We found that 1,6-HD treatment caused the enlargement of nucleosome clutches and their more uniform distribution in the nuclear space. At a megabase-scale, chromatin underwent moderate but irreversible perturbations that resulted in the partial mixing of A and B compartments. The removal of 1,6-HD from the culture medium did not allow chromatin to acquire initial configurations, and resulted in more compact repressed chromatin than in untreated cells. 1,6-HD treatment also weakened enhancer-promoter interactions and TAD insulation but did not considerably affect CTCF-dependent loops. Our results suggest that 1,6-HD-sensitive LLPS plays a limited role in chromatin spatial organization by constraining its folding patterns and facilitating compartmentalization at different levels.
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Affiliation(s)
- Sergey V Ulianov
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119992 Moscow, Russia
| | - Artem K Velichko
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, 119334 Moscow, Russia
- Institute for Translational Medicine and Biotechnology, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Mikhail D Magnitov
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, 119334 Moscow, Russia
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology (National Research University), 141701 Dolgoprudny, Russia
| | - Artem V Luzhin
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, 119334 Moscow, Russia
| | - Arkadiy K Golov
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
| | - Natalia Ovsyannikova
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia
| | - Igor I Kireev
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia
- V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology, and Perinatology, 117997 Moscow, Russia
| | - Alexey S Gavrikov
- Shemyakin−Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Alexander S Mishin
- Shemyakin−Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Azat K Garaev
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
| | - Alexander V Tyakht
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, 119334 Moscow, Russia
| | - Alexey A Gavrilov
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, 119334 Moscow, Russia
| | - Omar L Kantidze
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
| | - Sergey V Razin
- Institute of Gene Biology Russian Academy of Science, 119334 Moscow, Russia
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8
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Novo CL. A Tale of Two States: Pluripotency Regulation of Telomeres. Front Cell Dev Biol 2021; 9:703466. [PMID: 34307383 PMCID: PMC8300013 DOI: 10.3389/fcell.2021.703466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/08/2021] [Indexed: 01/01/2023] Open
Abstract
Inside the nucleus, chromatin is functionally organized and maintained as a complex three-dimensional network of structures with different accessibility such as compartments, lamina associated domains, and membraneless bodies. Chromatin is epigenetically and transcriptionally regulated by an intricate and dynamic interplay of molecular processes to ensure genome stability. Phase separation, a process that involves the spontaneous organization of a solution into separate phases, has been proposed as a mechanism for the timely coordination of several cellular processes, including replication, transcription and DNA repair. Telomeres, the repetitive structures at the end of chromosomes, are epigenetically maintained in a repressed heterochromatic state that prevents their recognition as double-strand breaks (DSB), avoiding DNA damage repair and ensuring cell proliferation. In pluripotent embryonic stem cells, telomeres adopt a non-canonical, relaxed epigenetic state, which is characterized by a low density of histone methylation and expression of telomere non-coding transcripts (TERRA). Intriguingly, this telomere non-canonical conformation is usually associated with chromosome instability and aneuploidy in somatic cells, raising the question of how genome stability is maintained in a pluripotent background. In this review, we will explore how emerging technological and conceptual developments in 3D genome architecture can provide novel mechanistic perspectives for the pluripotent epigenetic paradox at telomeres. In particular, as RNA drives the formation of LLPS, we will consider how pluripotency-associated high levels of TERRA could drive and coordinate phase separation of several nuclear processes to ensure genome stability. These conceptual advances will provide a better understanding of telomere regulation and genome stability within the highly dynamic pluripotent background.
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Affiliation(s)
- Clara Lopes Novo
- The Francis Crick Institute, London, United Kingdom
- Imperial College London, London, United Kingdom
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Bitman-Lotan E, Orian A. Nuclear organization and regulation of the differentiated state. Cell Mol Life Sci 2021; 78:3141-3158. [PMID: 33507327 PMCID: PMC8038961 DOI: 10.1007/s00018-020-03731-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 12/01/2020] [Accepted: 12/04/2020] [Indexed: 12/22/2022]
Abstract
Regulation of the differentiated identity requires active and continued supervision. Inability to maintain the differentiated state is a hallmark of aging and aging-related disease. To maintain cellular identity, a network of nuclear regulators is devoted to silencing previous and non-relevant gene programs. This network involves transcription factors, epigenetic regulators, and the localization of silent genes to heterochromatin. Together, identity supervisors mold and maintain the unique nuclear environment of the differentiated cell. This review describes recent discoveries regarding mechanisms and regulators that supervise the differentiated identity and protect from de-differentiation, tumorigenesis, and attenuate forced somatic cell reprograming. The review focuses on mechanisms involved in H3K9me3-decorated heterochromatin and the importance of nuclear lamins in cell identity. We outline how the biophysical properties of these factors are involved in self-compartmentalization of heterochromatin and cell identity. Finally, we discuss the relevance of these regulators to aging and age-related disease.
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Affiliation(s)
- Eliya Bitman-Lotan
- Rappaport Research Institute and Faculty of Medicine, The Rappaport Faculty of Medicine Technion-IIT, Technion Integrative Cancer Center (TICC), Technion-Israel Institute of Technology, Bat-Galim, 3109610, Haifa, Israel
| | - Amir Orian
- Rappaport Research Institute and Faculty of Medicine, The Rappaport Faculty of Medicine Technion-IIT, Technion Integrative Cancer Center (TICC), Technion-Israel Institute of Technology, Bat-Galim, 3109610, Haifa, Israel.
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