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Wong LH, Tremethick DJ. Multifunctional histone variants in genome function. Nat Rev Genet 2024:10.1038/s41576-024-00759-1. [PMID: 39138293 DOI: 10.1038/s41576-024-00759-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2024] [Indexed: 08/15/2024]
Abstract
Histones are integral components of eukaryotic chromatin that have a pivotal role in the organization and function of the genome. The dynamic regulation of chromatin involves the incorporation of histone variants, which can dramatically alter its structural and functional properties. Contrary to an earlier view that limited individual histone variants to specific genomic functions, new insights have revealed that histone variants exert multifaceted roles involving all aspects of genome function, from governing patterns of gene expression at precise genomic loci to participating in genome replication, repair and maintenance. This conceptual change has led to a new understanding of the intricate interplay between chromatin and DNA-dependent processes and how this connection translates into normal and abnormal cellular functions.
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Affiliation(s)
- Lee H Wong
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - David J Tremethick
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capial Territory, Australia.
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2
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Yin X, Zeng D, Liao Y, Tang C, Li Y. The Function of H2A Histone Variants and Their Roles in Diseases. Biomolecules 2024; 14:993. [PMID: 39199381 PMCID: PMC11352661 DOI: 10.3390/biom14080993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Revised: 08/06/2024] [Accepted: 08/09/2024] [Indexed: 09/01/2024] Open
Abstract
Epigenetic regulation, which is characterized by reversible and heritable genetic alterations without changing DNA sequences, has recently been increasingly studied in diseases. Histone variant regulation is an essential component of epigenetic regulation. The substitution of canonical histones by histone variants profoundly alters the local chromatin structure and modulates DNA accessibility to regulatory factors, thereby exerting a pivotal influence on gene regulation and DNA damage repair. Histone H2A variants, mainly including H2A.Z, H2A.B, macroH2A, and H2A.X, are the most abundant identified variants among all histone variants with the greatest sequence diversity. Harboring varied chromatin occupancy and structures, histone H2A variants perform distinct functions in gene transcription and DNA damage repair. They are implicated in multiple pathophysiological mechanisms and the emergence of different illnesses. Cancer, embryonic development abnormalities, neurological diseases, metabolic diseases, and heart diseases have all been linked to histone H2A variant alterations. This review focuses on the functions of H2A histone variants in mammals, including H2A.Z, H2A.B, macroH2A, and H2A.X, and their current roles in various diseases.
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Affiliation(s)
- Xuemin Yin
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha 410011, China; (X.Y.); (D.Z.); (Y.L.); (C.T.)
- Hunan Key Laboratory of Kidney Disease and Blood Purification in Hunan Province, Changsha 410011, China
| | - Dong Zeng
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha 410011, China; (X.Y.); (D.Z.); (Y.L.); (C.T.)
- Hunan Key Laboratory of Kidney Disease and Blood Purification in Hunan Province, Changsha 410011, China
| | - Yingjun Liao
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha 410011, China; (X.Y.); (D.Z.); (Y.L.); (C.T.)
- Hunan Key Laboratory of Kidney Disease and Blood Purification in Hunan Province, Changsha 410011, China
| | - Chengyuan Tang
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha 410011, China; (X.Y.); (D.Z.); (Y.L.); (C.T.)
- Hunan Key Laboratory of Kidney Disease and Blood Purification in Hunan Province, Changsha 410011, China
| | - Ying Li
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha 410011, China; (X.Y.); (D.Z.); (Y.L.); (C.T.)
- Hunan Key Laboratory of Kidney Disease and Blood Purification in Hunan Province, Changsha 410011, China
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3
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Silva JCR. Reprogramming Cell Identity: Past Lessons, Challenges, and Future Directions. Cell Reprogram 2023; 25:183-186. [PMID: 37847897 DOI: 10.1089/cell.2023.0100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2023] Open
Abstract
Reprogramming is traditionally defined as the fate conversion of a cell to a stage of increased developmental potential. In its broader meaning, the reprogramming term is also applied to all forms of cell fate conversion that do not follow a developmental trajectory. Reprogramming is now a well-established field of research that gained rapid progress upon the advent of induced pluripotency. In this perspective, I reflect on the reprogramming lessons of the past, in the contributions to other fields of research and on the potential transformative future use of reprogrammed cells and of its cell derivatives.
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Affiliation(s)
- José C R Silva
- Guangzhou National Laboratory, Guangzhou International Bio Island, Guangzhou, China
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4
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Karam G, Molaro A. Casting histone variants during mammalian reproduction. Chromosoma 2023:10.1007/s00412-023-00803-9. [PMID: 37347315 PMCID: PMC10356639 DOI: 10.1007/s00412-023-00803-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/31/2023] [Accepted: 06/05/2023] [Indexed: 06/23/2023]
Abstract
During mammalian reproduction, germ cell chromatin packaging is key to prepare parental genomes for fertilization and to initiate embryonic development. While chromatin modifications such as DNA methylation and histone post-translational modifications are well known to carry regulatory information, histone variants have received less attention in this context. Histone variants alter the stability, structure and function of nucleosomes and, as such, contribute to chromatin organization in germ cells. Here, we review histone variants expression dynamics during the production of male and female germ cells, and what is currently known about their parent-of-origin effects during reproduction. Finally, we discuss the apparent conundrum behind these important functions and their recent evolutionary diversification.
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Affiliation(s)
- Germaine Karam
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, INSERM U1103, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Antoine Molaro
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, INSERM U1103, Université Clermont Auvergne, Clermont-Ferrand, France.
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5
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Nikolic A, Maule F, Bobyn A, Ellestad K, Paik S, Marhon SA, Mehdipour P, Lun X, Chen HM, Mallard C, Hay AJ, Johnston MJ, Gafuik CJ, Zemp FJ, Shen Y, Ninkovic N, Osz K, Labit E, Berger ND, Brownsey DK, Kelly JJ, Biernaskie J, Dirks PB, Derksen DJ, Jones SJM, Senger DL, Chan JA, Mahoney DJ, De Carvalho DD, Gallo M. macroH2A2 antagonizes epigenetic programs of stemness in glioblastoma. Nat Commun 2023; 14:3062. [PMID: 37244935 PMCID: PMC10224928 DOI: 10.1038/s41467-023-38919-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 05/22/2023] [Indexed: 05/29/2023] Open
Abstract
Self-renewal is a crucial property of glioblastoma cells that is enabled by the choreographed functions of chromatin regulators and transcription factors. Identifying targetable epigenetic mechanisms of self-renewal could therefore represent an important step toward developing effective treatments for this universally lethal cancer. Here we uncover an epigenetic axis of self-renewal mediated by the histone variant macroH2A2. With omics and functional assays deploying patient-derived in vitro and in vivo models, we show that macroH2A2 shapes chromatin accessibility at enhancer elements to antagonize transcriptional programs of self-renewal. macroH2A2 also sensitizes cells to small molecule-mediated cell death via activation of a viral mimicry response. Consistent with these results, our analyses of clinical cohorts indicate that high transcriptional levels of this histone variant are associated with better prognosis of high-grade glioma patients. Our results reveal a targetable epigenetic mechanism of self-renewal controlled by macroH2A2 and suggest additional treatment approaches for glioblastoma patients.
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Affiliation(s)
- Ana Nikolic
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Francesca Maule
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Anna Bobyn
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biological Sciences, Faculty of Science, University of Calgary, Calgary, AB, Canada
| | - Katrina Ellestad
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Seungil Paik
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | | | - Parinaz Mehdipour
- Princess Margaret Cancer Centre, Toronto, ON, Canada
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, UK
| | - Xueqing Lun
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Huey-Miin Chen
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Claire Mallard
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Alexander J Hay
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Michael J Johnston
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Christopher J Gafuik
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Franz J Zemp
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Yaoqing Shen
- Canada's Michael Smith Genome Sciences Centre, BC Cancer, Vancouver, BC, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Nicoletta Ninkovic
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Katalin Osz
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Elodie Labit
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Compararive Biology and Experimental Medicine, Faculty of Veterinary Medicine, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - N Daniel Berger
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Duncan K Brownsey
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Chemistry, Faculty of Science, University of Calgary, Calgary, AB, Canada
| | - John J Kelly
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jeff Biernaskie
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Compararive Biology and Experimental Medicine, Faculty of Veterinary Medicine, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Peter B Dirks
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Darren J Derksen
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Chemistry, Faculty of Science, University of Calgary, Calgary, AB, Canada
| | - Steven J M Jones
- Canada's Michael Smith Genome Sciences Centre, BC Cancer, Vancouver, BC, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Donna L Senger
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jennifer A Chan
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Douglas J Mahoney
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Daniel D De Carvalho
- Princess Margaret Cancer Centre, Toronto, ON, Canada
- Department of Medical Biophysics, Faculty of Science, University of Toronto, Toronto, ON, Canada
| | - Marco Gallo
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
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6
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Peng J, Zhang WJ, Zhang Q, Su YH, Tang LP. The dynamics of chromatin states mediated by epigenetic modifications during somatic cell reprogramming. Front Cell Dev Biol 2023; 11:1097780. [PMID: 36727112 PMCID: PMC9884706 DOI: 10.3389/fcell.2023.1097780] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 01/05/2023] [Indexed: 01/17/2023] Open
Abstract
Somatic cell reprogramming (SCR) is the conversion of differentiated somatic cells into totipotent or pluripotent cells through a variety of methods. Somatic cell reprogramming also provides a platform to investigate the role of chromatin-based factors in establishing and maintaining totipotency or pluripotency, since high expression of totipotency- or pluripotency-related genes usually require an active chromatin state. Several studies in plants or mammals have recently shed light on the molecular mechanisms by which epigenetic modifications regulate the expression of totipotency or pluripotency genes by altering their chromatin states. In this review, we present a comprehensive overview of the dynamic changes in epigenetic modifications and chromatin states during reprogramming from somatic cells to totipotent or pluripotent cells. In addition, we illustrate the potential role of DNA methylation, histone modifications, histone variants, and chromatin remodeling during somatic cell reprogramming, which will pave the way to developing reliable strategies for efficient cellular reprogramming.
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Affiliation(s)
| | | | | | - Ying Hua Su
- *Correspondence: Ying Hua Su, ; Li Ping Tang,
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7
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Ayala-Guerrero L, Claudio-Galeana S, Furlan-Magaril M, Castro-Obregón S. Chromatin Structure from Development to Ageing. Subcell Biochem 2023; 102:7-51. [PMID: 36600128 DOI: 10.1007/978-3-031-21410-3_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Nuclear structure influences genome architecture, which contributes to determine patterns of gene expression. Global changes in chromatin dynamics are essential during development and differentiation, and are one of the hallmarks of ageing. This chapter describes the molecular dynamics of chromatin structure that occur during development and ageing. In the first part, we introduce general information about the nuclear lamina, the chromatin structure, and the 3D organization of the genome. Next, we detail the molecular hallmarks found during development and ageing, including the role of DNA and histone modifications, 3D genome dynamics, and changes in the nuclear lamina. Within the chapter we discuss the implications that genome structure has on the mechanisms that drive development and ageing, and the physiological consequences when these mechanisms fail.
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Affiliation(s)
- Lorelei Ayala-Guerrero
- Departamento de Neurodesarrollo y Fisiología, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico
| | - Sherlyn Claudio-Galeana
- Departamento de Genética Molecular, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico
| | - Mayra Furlan-Magaril
- Departamento de Genética Molecular, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico.
| | - Susana Castro-Obregón
- Departamento de Neurodesarrollo y Fisiología, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico.
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8
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Sun KY, Guo SM, Cheng GP, Yin Y, He X, Zhou LQ. Cleavage-embryo genes and transposable elements are regulated by histone variant H2A.X. J Reprod Dev 2021; 67:307-312. [PMID: 34393157 PMCID: PMC8568613 DOI: 10.1262/jrd.2021-065] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During mammalian preimplantation development, stimulation of zygotic genome activation (ZGA) and transposable elements (TEs) shapes totipotency profiling. A rare mouse embryonic stem cells (mESCs) subpopulation is capable of transiently entering a state resembling 2-cell stage embryos, with subtypes of TEs expressed and ZGA genes transiently activated. In this study, we found that deletion of H2A.X in mESCs led to a significant upregulation of ZGA genes and misregulated TEs. ChIP-seq analysis indicated a direct association of H2A.X at the Dux locus for silencing the Dux gene and its downstream ZGA genes in mESCs. We also demonstrated that histone variant H2A.X is highly enriched in human cleavage embryos when ZGA genes and TEs are active. Therefore, we propose that H2A.X plays an important role in regulating ZGA genes and TEs to establish totipotency.
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Affiliation(s)
- Kai-Yi Sun
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei 430030, China
| | - Shi-Meng Guo
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei 430030, China
| | - Gui-Ping Cheng
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei 430030, China
| | - Ying Yin
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Hubei 430030, China
| | - Ximiao He
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Hubei 430030, China
| | - Li-Quan Zhou
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei 430030, China
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9
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Otero-Albiol D, Carnero A. Cellular senescence or stemness: hypoxia flips the coin. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2021; 40:243. [PMID: 34325734 PMCID: PMC8323321 DOI: 10.1186/s13046-021-02035-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 07/05/2021] [Indexed: 01/10/2023]
Abstract
Cellular senescence is a complex physiological state whose main feature is proliferative arrest. Cellular senescence can be considered the reverse of cell immortalization and continuous tumor growth. However, cellular senescence has many physiological functions beyond being a putative tumor suppressive trait. It remains unknown whether low levels of oxygen or hypoxia, which is a feature of every tissue in the organism, modulate cellular senescence, altering its capacity to suppress the limitation of proliferation. It has been observed that the lifespan of mammalian primary cells is increased under low oxygen conditions. Additionally, hypoxia promotes self-renewal and pluripotency maintenance in adult and embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and cancer stem cells (CSCs). In this study, we discuss the role of hypoxia facilitating senescence bypass during malignant transformation and acquisition of stemness properties, which all contribute to tumor development and cancer disease aggressiveness.
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Affiliation(s)
- Daniel Otero-Albiol
- Instituto de Biomedicina de Sevilla, IBIS, Hospital Universitario Virgen del Rocío, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Avda. Manuel Siurot s/n, 41013, Seville, Spain.,CIBER de CANCER, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Amancio Carnero
- Instituto de Biomedicina de Sevilla, IBIS, Hospital Universitario Virgen del Rocío, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Avda. Manuel Siurot s/n, 41013, Seville, Spain. .,CIBER de CANCER, Instituto de Salud Carlos III (ISCIII), Madrid, Spain.
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10
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Golson ML. Islet Epigenetic Impacts on β-Cell Identity and Function. Compr Physiol 2021; 11:1961-1978. [PMID: 34061978 DOI: 10.1002/cphy.c200004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The development and maintenance of differentiation is vital to the function of mature cells. Terminal differentiation is achieved by locking in the expression of genes essential for the function of those cells. Gene expression and its memory through generations of cell division is controlled by transcription factors and a host of epigenetic marks. In type 2 diabetes, β cells have altered gene expression compared to controls, accompanied by altered chromatin marks. Mutations, diet, and environment can all disrupt the implementation and preservation of the distinctive β-cell transcriptional signature. Understanding of the full complement of genomic control in β cells is still nascent. This article describes the known effects of histone marks and variants, DNA methylation, how they are regulated in the β cell, and how they affect cell-fate specification, maintenance, and lineage propagation. © 2021 American Physiological Society. Compr Physiol 11:1-18, 2021.
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Affiliation(s)
- Maria L Golson
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
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11
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Courtot L, Bournique E, Maric C, Guitton-Sert L, Madrid-Mencía M, Pancaldi V, Cadoret JC, Hoffmann JS, Bergoglio V. Low Replicative Stress Triggers Cell-Type Specific Inheritable Advanced Replication Timing. Int J Mol Sci 2021; 22:ijms22094959. [PMID: 34066960 PMCID: PMC8125030 DOI: 10.3390/ijms22094959] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/30/2021] [Accepted: 05/02/2021] [Indexed: 12/27/2022] Open
Abstract
DNA replication timing (RT), reflecting the temporal order of origin activation, is known as a robust and conserved cell-type specific process. Upon low replication stress, the slowing of replication forks induces well-documented RT delays associated to genetic instability, but it can also generate RT advances that are still uncharacterized. In order to characterize these advanced initiation events, we monitored the whole genome RT from six independent human cell lines treated with low doses of aphidicolin. We report that RT advances are cell-type-specific and involve large heterochromatin domains. Importantly, we found that some major late to early RT advances can be inherited by the unstressed next-cellular generation, which is a unique process that correlates with enhanced chromatin accessibility, as well as modified replication origin landscape and gene expression in daughter cells. Collectively, this work highlights how low replication stress may impact cellular identity by RT advances events at a subset of chromosomal domains.
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Affiliation(s)
- Lilas Courtot
- Centre de Recherches en Cancérologie de Toulouse (CRCT), UMR1037 Inserm, University Paul Sabatier III, ERL5294 CNRS, 2 Avenue Hubert Curien, 31037 Toulouse, France; (L.C.); (E.B.); (L.G.-S.); (M.M.-M.); (V.P.)
| | - Elodie Bournique
- Centre de Recherches en Cancérologie de Toulouse (CRCT), UMR1037 Inserm, University Paul Sabatier III, ERL5294 CNRS, 2 Avenue Hubert Curien, 31037 Toulouse, France; (L.C.); (E.B.); (L.G.-S.); (M.M.-M.); (V.P.)
| | - Chrystelle Maric
- Université de Paris, CNRS, Institut Jacques Monod, DNA Replication Pathologies Team, F-75006 Paris, France;
| | - Laure Guitton-Sert
- Centre de Recherches en Cancérologie de Toulouse (CRCT), UMR1037 Inserm, University Paul Sabatier III, ERL5294 CNRS, 2 Avenue Hubert Curien, 31037 Toulouse, France; (L.C.); (E.B.); (L.G.-S.); (M.M.-M.); (V.P.)
| | - Miguel Madrid-Mencía
- Centre de Recherches en Cancérologie de Toulouse (CRCT), UMR1037 Inserm, University Paul Sabatier III, ERL5294 CNRS, 2 Avenue Hubert Curien, 31037 Toulouse, France; (L.C.); (E.B.); (L.G.-S.); (M.M.-M.); (V.P.)
| | - Vera Pancaldi
- Centre de Recherches en Cancérologie de Toulouse (CRCT), UMR1037 Inserm, University Paul Sabatier III, ERL5294 CNRS, 2 Avenue Hubert Curien, 31037 Toulouse, France; (L.C.); (E.B.); (L.G.-S.); (M.M.-M.); (V.P.)
- Barcelona Supercomputing Center, 08034 Barcelona, Spain
| | - Jean-Charles Cadoret
- Université de Paris, CNRS, Institut Jacques Monod, DNA Replication Pathologies Team, F-75006 Paris, France;
- Correspondence: (J.-C.C.); (J.-S.H.); (V.B.)
| | - Jean-Sébastien Hoffmann
- Laboratoire de pathologie, Laboratoire d’excellence Toulouse Cancer, Institut Universitaire du Cancer-Toulouse, Oncopole, 1 Avenue Irène-Joliot-Curie, CEDEX, 31059 Toulouse, France
- Correspondence: (J.-C.C.); (J.-S.H.); (V.B.)
| | - Valérie Bergoglio
- Centre de Recherches en Cancérologie de Toulouse (CRCT), UMR1037 Inserm, University Paul Sabatier III, ERL5294 CNRS, 2 Avenue Hubert Curien, 31037 Toulouse, France; (L.C.); (E.B.); (L.G.-S.); (M.M.-M.); (V.P.)
- Correspondence: (J.-C.C.); (J.-S.H.); (V.B.)
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12
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The diagnostic and prognostic value of H2AFY in hepatocellular carcinoma. BMC Cancer 2021; 21:418. [PMID: 33858382 PMCID: PMC8051056 DOI: 10.1186/s12885-021-08161-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 04/07/2021] [Indexed: 12/17/2022] Open
Abstract
Background The potential correlation between H2AFY (also known as MacroH2A1) and the clinical characteristics of hepatocellular carcinoma (HCC) patients was analysed through gene expression profiles and clinical data in The Cancer Genome Atlas (TCGA) database, and the diagnostic and prognostic value of H2AFY in HCC was discussed. Methods The gene expression data of HCC and the corresponding clinical characteristics of HCC patients were downloaded from the TCGA database. The differences in H2AFY in normal liver tissues and HCC were analysed. The relationship between H2AFY and clinical characteristics was analysed by Wilcoxon signed-rank test, logistic regression and Kruskal-Wallis test. The Kaplan-Meier method and the Cox regression method were used to analyse the relationship between overall survival and clinical characteristics of the patients. An ROC curve was used to predict the diagnostic value of H2AFY in HCC. Gene set enrichment analysis (GSEA) was used to analyse the pathway enrichment of H2AFY. Result Compared with normal liver tissues, H2AFY was significantly highly expressed in HCC. H2AFY was positively correlated with the age, clinical stage, G stage (grade) and T stage (tumor stage) of liver cancer patients. Higher H2AFY expression predicted a poor prognosis in HCC patients. Cox regression analysis suggested that H2AFY was an independent risk factor for the prognosis of HCC patients. The ROC curve suggested that H2AFY had certain diagnostic value in HCC. GSEA suggested that H2AFY was correlated with lipid metabolism and a variety of tumour pathways. Conclusion Our study showed that H2AFY was significantly overexpressed in HCC. H2AFY may be a potential diagnostic and prognostic marker for HCC, and high expression of H2AFY predicts a poor prognosis in patients with HCC.
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13
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Abstract
Cancer is a complex disease characterized by loss of cellular homeostasis through genetic and epigenetic alterations. Emerging evidence highlights a role for histone variants and their dedicated chaperones in cancer initiation and progression. Histone variants are involved in processes as diverse as maintenance of genome integrity, nuclear architecture and cell identity. On a molecular level, histone variants add a layer of complexity to the dynamic regulation of transcription, DNA replication and repair, and mitotic chromosome segregation. Because these functions are critical to ensure normal proliferation and maintenance of cellular fate, cancer cells are defined by their capacity to subvert them. Hijacking histone variants and their chaperones is emerging as a common means to disrupt homeostasis across a wide range of cancers, particularly solid tumours. Here we discuss histone variants and histone chaperones as tumour-promoting or tumour-suppressive players in the pathogenesis of cancer.
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Affiliation(s)
| | - Dan Filipescu
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
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14
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Giallongo S, Rehakova D, Raffaele M, Lo Re O, Koutna I, Vinciguerra M. Redox and Epigenetics in Human Pluripotent Stem Cells Differentiation. Antioxid Redox Signal 2021; 34:335-349. [PMID: 32567336 DOI: 10.1089/ars.2019.7983] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Significance: Since their discovery, induced pluripotent stem cells (iPSCs) had generated considerable interest in the scientific community for their great potential in regenerative medicine, disease modeling, and cell-based therapeutic approach, due to their unique characteristics of self-renewal and pluripotency. Recent Advances: Technological advances in iPSC genome-wide epigenetic profiling led to the elucidation of the epigenetic control of cellular identity during nuclear reprogramming. Moreover, iPSC physiology and metabolism are tightly regulated by oxidation-reduction events that mainly occur during the respiratory chain. In theory, iPSC-derived differentiated cells would be ideal for stem cell transplantation as autologous cells from donors, as the risks of rejection are minimal. Critical Issues: However, iPSCs experience high oxidative stress that, in turn, confers a high risk of increased genomic instability, which is most often linked to DNA repair deficiencies. Genomic instability has to be assessed before iPSCs can be used in therapeutic designs. Future Directions: This review will particularly focus on the links between redox balance and epigenetic modifications-in particular based on the histone variant macroH2A1-that determine DNA damage response in iPSCs and derived differentiated cells, and that might be exploited to decrease the teratogenic potential on iPSC transplantation. Antioxid. Redox Signal. 34, 335-349.
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Affiliation(s)
- Sebastiano Giallongo
- International Clinical Research Center, St' Anne's University Hospital, Brno, Czech Republic.,Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Daniela Rehakova
- International Clinical Research Center, St' Anne's University Hospital, Brno, Czech Republic.,Faculty of Informatics, Centre for Biomedical Image Analysis, Masaryk University, Brno, Czech Republic
| | - Marco Raffaele
- International Clinical Research Center, St' Anne's University Hospital, Brno, Czech Republic
| | - Oriana Lo Re
- International Clinical Research Center, St' Anne's University Hospital, Brno, Czech Republic
| | - Irena Koutna
- International Clinical Research Center, St' Anne's University Hospital, Brno, Czech Republic.,Faculty of Informatics, Centre for Biomedical Image Analysis, Masaryk University, Brno, Czech Republic
| | - Manlio Vinciguerra
- International Clinical Research Center, St' Anne's University Hospital, Brno, Czech Republic.,Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
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15
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Varghese PC, Rajam SM, Nandy D, Jory A, Mukherjee A, Dutta D. Histone chaperone APLF level dictates the implantation of mouse embryos. J Cell Sci 2021; 134:jcs.246900. [PMID: 33277378 DOI: 10.1242/jcs.246900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 11/25/2020] [Indexed: 11/20/2022] Open
Abstract
Our recent findings demonstrated that the histone chaperone and DNA repair factor aprataxin and PNK-like factor (APLF) could regulate epithelial to mesenchymal transition (EMT) during the reprogramming of murine fibroblasts and in breast cancer metastasis. Therefore, we investigated the function of APLF in EMT associated with mouse development. Here, we show that APLF is predominantly enhanced in trophectoderm (TE) and lineages derived from TE in pre- and post-implantation embryos. Downregulation of APLF induced the hatching of embryos in vitro, with a significant increase in Cdh1 and Cdx2 expression. Aplf short hairpin RNA-microinjected embryos failed to implant in vivo Rescue experiments neutralized the knockdown effects of APLF both in vitro and in vivo Reduced expression of Snai2 and Tead4, and the gain in Cdh1 and sFlt1 (also known as Flt1) level, marked the differentiation of APLF-knocked down trophoblast stem cells that might contribute towards the impaired implantation of embryos. Hence, our findings suggest a novel role for APLF during implantation and post-implantation development of mouse embryos. We anticipate that APLF might contribute to the establishment of maternal-fetal connection, as its fine balance is required to achieve implantation and thereby attain proper pregnancy.
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Affiliation(s)
- Pallavi Chinnu Varghese
- Rajiv Gandhi Centre for Biotechnology, Regenerative Biology Program, Thycaud PO, Poojappura, Thiruvananthapuram 695014, Kerala, India.,Department of Biotechnology, Manipal Academy of Higher Education, Manipal, Karnataka State 576104, India
| | - Sruthy Manuraj Rajam
- Rajiv Gandhi Centre for Biotechnology, Regenerative Biology Program, Thycaud PO, Poojappura, Thiruvananthapuram 695014, Kerala, India.,Department of Biotechnology, Manipal Academy of Higher Education, Manipal, Karnataka State 576104, India
| | - Debparna Nandy
- Rajiv Gandhi Centre for Biotechnology, Regenerative Biology Program, Thycaud PO, Poojappura, Thiruvananthapuram 695014, Kerala, India
| | - Aurelie Jory
- Mouse Genome Engineering Facility, National Centre for Biological Sciences, Bellary Road, Bengaluru, Karnataka 560065, India
| | - Ananda Mukherjee
- Rajiv Gandhi Centre for Biotechnology, Cancer Research Program, Thycaud PO, Poojappura, Thiruvananthapuram 695014, Kerala, India
| | - Debasree Dutta
- Rajiv Gandhi Centre for Biotechnology, Regenerative Biology Program, Thycaud PO, Poojappura, Thiruvananthapuram 695014, Kerala, India
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16
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LSH mediates gene repression through macroH2A deposition. Nat Commun 2020; 11:5647. [PMID: 33159050 PMCID: PMC7648012 DOI: 10.1038/s41467-020-19159-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 09/22/2020] [Indexed: 02/07/2023] Open
Abstract
The human Immunodeficiency Centromeric Instability Facial Anomalies (ICF) 4 syndrome is a severe disease with increased mortality caused by mutation in the LSH gene. Although LSH belongs to a family of chromatin remodeling proteins, it remains unknown how LSH mediates its function on chromatin in vivo. Here, we use chemical-induced proximity to rapidly recruit LSH to an engineered locus and find that LSH specifically induces macroH2A1.2 and macroH2A2 deposition in an ATP-dependent manner. Tethering of LSH induces transcriptional repression and silencing is dependent on macroH2A deposition. Loss of LSH decreases macroH2A enrichment at repeat sequences and results in transcriptional reactivation. Likewise, reduction of macroH2A by siRNA interference mimicks transcriptional reactivation. ChIP-seq analysis confirmed that LSH is a major regulator of genome-wide macroH2A distribution. Tethering of ICF4 mutations fails to induce macroH2A deposition and ICF4 patient cells display reduced macroH2A deposition and transcriptional reactivation supporting a pathogenic role for altered marcoH2A deposition. We propose that LSH is a major chromatin modulator of the histone variant macroH2A and that its ability to insert marcoH2A into chromatin and transcriptionally silence is disturbed in the ICF4 syndrome. The human ICF 4 syndrome is caused by mutation of the chromatin remodeller LSH. Here, the authors show that LSH depletion disrupts the ability of histone variant macroH2A to insert into chromatin and silence transcription.
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17
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Ferrand J, Rondinelli B, Polo SE. Histone Variants: Guardians of Genome Integrity. Cells 2020; 9:E2424. [PMID: 33167489 PMCID: PMC7694513 DOI: 10.3390/cells9112424] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/30/2020] [Accepted: 11/03/2020] [Indexed: 12/12/2022] Open
Abstract
Chromatin integrity is key for cell homeostasis and for preventing pathological development. Alterations in core chromatin components, histone proteins, recently came into the spotlight through the discovery of their driving role in cancer. Building on these findings, in this review, we discuss how histone variants and their associated chaperones safeguard genome stability and protect against tumorigenesis. Accumulating evidence supports the contribution of histone variants and their chaperones to the maintenance of chromosomal integrity and to various steps of the DNA damage response, including damaged chromatin dynamics, DNA damage repair, and damage-dependent transcription regulation. We present our current knowledge on these topics and review recent advances in deciphering how alterations in histone variant sequence, expression, and deposition into chromatin fuel oncogenic transformation by impacting cell proliferation and cell fate transitions. We also highlight open questions and upcoming challenges in this rapidly growing field.
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Affiliation(s)
| | | | - Sophie E. Polo
- Epigenetics & Cell Fate Centre, UMR7216 CNRS, Université de Paris, 75013 Paris, France; (J.F.); (B.R.)
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18
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Abstract
Derivation of induced Pluripotent Stem Cells (iPSCs) by reprogramming somatic cells to a pluripotent state has revolutionized stem cell research. Ensuing this, various groups have used genetic and non-genetic approaches to generate iPSCs from numerous cell types. However, achieving a pluripotent state in most of the reprogramming studies is marred by serious limitations such as low reprogramming efficiency and slow kinetics. These limitations are mainly due to the presence of potent barriers that exist during reprogramming when a mature cell is coaxed to achieve a pluripotent state. Several studies have revealed that intrinsic factors such as non-optimal stoichiometry of reprogramming factors, specific signaling pathways, cellular senescence, pluripotency-inhibiting transcription factors and microRNAs act as a roadblock. In addition, the epigenetic state of somatic cells and specific epigenetic modifications that occur during reprogramming also remarkably impede the generation of iPSCs. In this review, we present a comprehensive overview of the barriers that inhibit reprogramming and the understanding of which will pave the way to develop safe strategies for efficient reprogramming.
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19
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Abstract
Histone variants regulate chromatin accessibility and gene transcription. Given their distinct properties and functions, histone varint substitutions allow for profound alteration of nucleosomal architecture and local chromatin landscape. Skeletal myogenesis driven by the key transcription factor MyoD is characterized by precise temporal regulation of myogenic genes. Timed substitution of variants within the nucleosomes provides a powerful means to ensure sequential expression of myogenic genes. Indeed, growing evidence has shown H3.3, H2A.Z, macroH2A, and H1b to be critical for skeletal myogenesis. However, the relative importance of various histone variants and their associated chaperones in myogenesis is not fully appreciated. In this review, we summarize the role that histone variants play in altering chromatin landscape to ensure proper muscle differentiation. The temporal regulation and cross talk between histones variants and their chaperones in conjunction with other forms of epigenetic regulation could be critical to understanding myogenesis and their involvement in myopathies.
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Affiliation(s)
- Nandini Karthik
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore , Singapore
| | - Reshma Taneja
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore , Singapore
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20
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Buchwalter A, Kaneshiro JM, Hetzer MW. Coaching from the sidelines: the nuclear periphery in genome regulation. Nat Rev Genet 2019; 20:39-50. [PMID: 30356165 DOI: 10.1038/s41576-018-0063-5] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The genome is packaged and organized nonrandomly within the 3D space of the nucleus to promote efficient gene expression and to faithfully maintain silencing of heterochromatin. The genome is enclosed within the nucleus by the nuclear envelope membrane, which contains a set of proteins that actively participate in chromatin organization and gene regulation. Technological advances are providing views of genome organization at unprecedented resolution and are beginning to reveal the ways that cells co-opt the structures of the nuclear periphery for nuclear organization and gene regulation. These genome regulatory roles of proteins of the nuclear periphery have important influences on development, disease and ageing.
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Affiliation(s)
- Abigail Buchwalter
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA.,Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA.,Department of Physiology, University of California San Francisco, San Francisco, CA, USA
| | - Jeanae M Kaneshiro
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Martin W Hetzer
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA.
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21
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Zebrafish macroH2A variants have distinct embryo localization and function. Sci Rep 2019; 9:8632. [PMID: 31201343 PMCID: PMC6570772 DOI: 10.1038/s41598-019-45058-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 05/29/2019] [Indexed: 11/08/2022] Open
Abstract
Mouse and cell-based studies have shown that macroH2A histone variants predominantly associate with heterochromatin. Functional studies found that macroH2As are involved in gene repression, inhibiting the acquisition of pluripotency and preserving cell differentiation. However, only a few studies have analysed the role of macroH2A during early embryo development. We report the development of transgenic zebrafish lines expressing macroH2A isoforms (mH2A1 and mH2A2) fusion proteins (with GFP) under identified endogenous promoters. We found that mH2A1 and mH2A2 have different spatial and temporal expression patterns during embryonic development. mH2A1 is expressed mostly in the extraembryonic Yolk Syncytial Layer (YSL) starting before shield stage and decreasing once morphogenesis is completed. mH2A2 expression lags behind mH2A1, becoming evident at 24 hpf, within the whole body of the embryo proper. Our ChIP-seq analysis showed that mH2A1 and mH2A2 bind to different DNA regions, changing dramatically after gastrulation. We further analysed RNA-seq data and showed that there is not a general/unspecific repressing function of mH2A1 or mH2A2 associated with heterochromatin but a fine regulation depending on cell types and stage of development. mH2A1 downregulates DNA expression in specific cells and embryo stages and its effect is independent of heterochromatin formation but it is correlated with nucleus quiescence instead. Whereas mH2A2 DNA association correlates with upregulation of differentially expressed genes between 75% epiboly and 24 hpf stages. Our data provide information for underlying molecules that participate in crucial early developmental events, and open new venues to explore mH2A related mechanisms that involve cell proliferation, differentiation, migration and metabolism.
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22
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Sato H, Wu B, Delahaye F, Singer RH, Greally JM. Retargeting of macroH2A following mitosis to cytogenetic-scale heterochromatic domains. J Cell Biol 2019; 218:1810-1823. [PMID: 31110057 PMCID: PMC6548134 DOI: 10.1083/jcb.201811109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/20/2019] [Accepted: 04/19/2019] [Indexed: 12/12/2022] Open
Abstract
How macroH2A, a histone variant involved in silencing gene expression, is inherited from parent to daughter cells is unclear. Using a combination of imaging, biochemical, and genomic approaches, Sato et al. describe how newly synthesized macroH2A is incorporated predominantly in the G1 phase of human mitosis, targeting heterochromatic regions. The heritability of chromatin states through cell division is a potential contributor to the epigenetic maintenance of cellular memory of prior states. The macroH2A histone variant has properties of a regulator of epigenetic cell memory, including roles controlling gene silencing and cell differentiation. Its mechanisms of regional genomic targeting and maintenance through cell division are unknown. Here, we combined in vivo imaging with biochemical and genomic approaches to show that human macroH2A is incorporated into chromatin in the G1 phase of the cell cycle following DNA replication. The newly incorporated macroH2A retargets the same large heterochromatic domains where macroH2A was already enriched in the previous cell cycle. It remains heterotypic, targeting individual nucleosomes that do not already contain a macroH2A molecule. The pattern observed resembles that of a new deposition of centromeric histone variants during the cell cycle, indicating mechanistic similarities for macrodomain-scale regulation of epigenetic properties of the cell.
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Affiliation(s)
- Hanae Sato
- Center for Epigenomics and Department of Genetics, Albert Einstein College of Medicine, Bronx, NY.,Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY
| | - Bin Wu
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY.,Gruss Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY
| | - Fabien Delahaye
- Center for Epigenomics and Department of Genetics, Albert Einstein College of Medicine, Bronx, NY.,Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, Bronx, NY
| | - Robert H Singer
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY .,Gruss Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY.,Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY.,Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA
| | - John M Greally
- Center for Epigenomics and Department of Genetics, Albert Einstein College of Medicine, Bronx, NY
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23
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Vieira-Silva TS, Monteiro-Reis S, Barros-Silva D, Ramalho-Carvalho J, Graça I, Carneiro I, Martins AT, Oliveira J, Antunes L, Hurtado-Bagès S, Buschbeck M, Henrique R, Jerónimo C. Histone variant MacroH2A1 is downregulated in prostate cancer and influences malignant cell phenotype. Cancer Cell Int 2019; 19:112. [PMID: 31164793 PMCID: PMC6489299 DOI: 10.1186/s12935-019-0835-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 04/23/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Prostate cancer (PCa), a major cause of cancer-related morbidity and mortality worldwide and mostly asymptomatic at earliest stages, is characterized by disruption of genetic and epigenetic balance. A better understanding of how those mechanisms orchestrate disease might improve diagnostic and prognostic tools, allowing for improvements in treatment efficacy. Replacement of canonical histones, an epigenetic mechanism, is highly conserved among species and altered expression of histones variants (e.g., MacroH2A1) has been associated with tumorigenesis. H2AFY gene encodes two isoforms of H2A histone variant MacroH2A1: MacroH2A1.1 and MacroH2A1.2. Specifically, MacroH2A1.1 isoform inhibits cell proliferation and promotes cellular differentiation. Because the contribution of this histone variant to carcinogenesis has been reported in several cancer types, but not for PCa, we aimed to investigate the contribution of MacroH2A1 for prostate carcinogenesis. METHODS MacroH2A1, MacroH2A1.1 and MacroH2A1.2 isoforms and the corresponding splicing regulators transcript levels were evaluated by RT-qPCR, in a tissue cohort composed by PCa, prostatic intraepithelial neoplasia (PIN) and normal prostate cases. Knockdown for MacroH2A1 and MacroH2A1.1 was performed through lentiviral transduction in DU145 cells, and MacroH2A1.1 overexpression was achieved in LNCaP cells by plasmid transfection, followed by functional assays. Biological and/or experimental replicates were performed when necessary, and specific statistical tests were applied to perform data analysis. RESULTS MacroH2A1.1 transcript levels were downregulated in PIN and primary PCa compared to normal prostate tissues. The same was found for QKI, a MacroH2A1.1's splicing regulator. Moreover, lower MacroH2A1.1 and QKI expression levels associated with less differentiated tumors (Gleason score ≥ 7). Interestingly, MacroH2A1.1, but more impressively DDX17 (AUC = 0.93; p < 0.0001) and QKI (AUC = 0.94; p < 0.0001), accurately discriminated cancerous from noncancerous prostate tissues. Furthermore, in PCa cell lines, total MacroH2A1 knockdown augmented malignant features, whereas MacroH2A1.1 overexpression impressively attenuated the malignant phenotype. CONCLUSIONS Overall, our data, derived from primary PCa tissues and cell lines, anticipate a tumor suppressive role for MacroH2A1, particularly for the MacroH2A1.1 isoform, in prostate carcinogenesis.
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Affiliation(s)
- Tânia Soraia Vieira-Silva
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Sara Monteiro-Reis
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Daniela Barros-Silva
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - João Ramalho-Carvalho
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Inês Graça
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Isa Carneiro
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
- Department of Pathology, Portuguese Oncology Institute of Porto (IPO Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Ana Teresa Martins
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
- Department of Pathology, Portuguese Oncology Institute of Porto (IPO Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Jorge Oliveira
- Department of Urology, Portuguese Oncology Institute of Porto (IPO Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Luis Antunes
- Department of Epidemiology, Portuguese Oncology Institute of Porto (IPO Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Sarah Hurtado-Bagès
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO-Germans Trias i Pujol, Campus Can Ruti, 08916 Badalona, Spain
- Program for Predictive and Personalized Medicine of Cancer, Germans Trias i Pujol Research Institute (PMPPC-IGTP), Barcelona, Spain
| | - Marcus Buschbeck
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO-Germans Trias i Pujol, Campus Can Ruti, 08916 Badalona, Spain
- Program for Predictive and Personalized Medicine of Cancer, Germans Trias i Pujol Research Institute (PMPPC-IGTP), Barcelona, Spain
| | - Rui Henrique
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
- Department of Pathology, Portuguese Oncology Institute of Porto (IPO Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
- Department of Pathology and Molecular Immunology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Carmen Jerónimo
- Cancer Biology & Epigenetics Group, Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Research Center-LAB 3, F Bdg., 1st Floor, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
- Department of Pathology and Molecular Immunology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
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24
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Histone variant macroH2A: from chromatin deposition to molecular function. Essays Biochem 2019; 63:59-74. [DOI: 10.1042/ebc20180062] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 01/01/2023]
Abstract
Abstract
The eukaryotic genome is regulated in the context of chromatin. Specialized histones, known as histone variants, incorporate into chromatin to replace their canonical counterparts and represent an important layer of regulation to diversify the structural characteristics and functional outputs of chromatin. MacroH2A is an unusual histone variant with a bulky C-terminal non-histone domain that distinguishes it from all other histones. It is a critical player in stabilizing differentiated cell identity by posing as a barrier to somatic cell reprogramming toward pluripotency and acts as a tumor suppressor in a wide range of cancers. MacroH2A histones are generally regarded as repressive variants that are enriched at the inactive X chromosome (Xi) and broad domains across autosomal chromatin. Recent studies have shed light on to how macroH2A influences transcriptional outputs within distinct genomic contexts and revealed new intriguing molecular functions of macroH2A variants beyond transcriptional regulation. Furthermore, the mechanisms of its mysterious chromatin deposition are beginning to be unraveled, facilitating our understanding of its complex regulation of genome function.
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25
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MacroH2A1 chromatin specification requires its docking domain and acetylation of H2B lysine 20. Nat Commun 2018; 9:5143. [PMID: 30510186 PMCID: PMC6277393 DOI: 10.1038/s41467-018-07189-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 10/13/2018] [Indexed: 12/23/2022] Open
Abstract
The histone variant macroH2A1 localizes to two functionally distinct chromatin subtypes marked by either H3K27me3 or H2B acetylations, where it is thought to directly regulate transcription. The recent finding, that macroH2A1 regulates mitochondrial respiration by globally dampening PARP activity, requires the field to re-evaluate which functions of macroH2A1 are due to global effects on cellular metabolism and which are direct effects determined by macroH2A1 chromatin localization. Here, we demonstrate macroH2A1 incorporation into H2B-acetylated chromatin requires a feature in its histone-fold domain, distinguishing this process from incorporation into H3K27me3-containing chromatin in which multiple features of macroH2A1 are sufficient for targeting. In addition, we identify H2BK20 acetylation as a critical modification required to target macroH2A1 to H2B-acetylated chromatin. Our findings have allowed us to definitively establish that macroH2A1's regulation of an important transcriptional program, the senescence-associated secretory phenotype (SASP), requires its accurate genomic localization.
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26
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Hurtado-Bagès S, Guberovic I, Buschbeck M. The MacroH2A1.1 - PARP1 Axis at the Intersection Between Stress Response and Metabolism. Front Genet 2018; 9:417. [PMID: 30356649 PMCID: PMC6189284 DOI: 10.3389/fgene.2018.00417] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 09/06/2018] [Indexed: 12/12/2022] Open
Abstract
The exchange of replication-coupled canonical histones by histone variants endows chromatin with specific features. The replacement of the canonical H2A histone for the histone variant macroH2A is one of the most remarkable epigenetic modifications. The three vertebrate macroH2A proteins have a unique tripartite structure consisting of H2A-like domain, unstructured linker, and macrodomain. Macrodomains are ancient globular folds that are able to bind nicotinamide adenine dinucleotide (NAD+) derived metabolites. Here, we will briefly describe the physiological relevance of the metabolite binding in the context of chromatin. In particular, we will focus on the macroH2A1.1 isoform that binds ADP-ribose and poly-ADP-ribose polymerase 1 (PARP1) enzyme, a cellular stress sensor. We will discuss the impact of this interaction in the context of cancer, senescence, cell stress and energy metabolism.
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Affiliation(s)
- Sarah Hurtado-Bagès
- Josep Carreras Leukaemia Research Institute, Campus ICO-Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain.,Ph.D. Program in Biomedicine, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Iva Guberovic
- Josep Carreras Leukaemia Research Institute, Campus ICO-Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain.,Ph.D. Program in Biomedicine, Faculty of Pharmacy and Food Science, University of Barcelona, Barcelona, Spain
| | - Marcus Buschbeck
- Josep Carreras Leukaemia Research Institute, Campus ICO-Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain.,Program for Predictive and Personalized Medicine of Cancer, Germans Trias i Pujol Research Institute (PMPPC-IGTP), Badalona, Spain
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27
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Lo Re O, Douet J, Buschbeck M, Fusilli C, Pazienza V, Panebianco C, Castracani CC, Mazza T, Li Volti G, Vinciguerra M. Histone variant macroH2A1 rewires carbohydrate and lipid metabolism of hepatocellular carcinoma cells towards cancer stem cells. Epigenetics 2018; 13:829-845. [PMID: 30165787 DOI: 10.1080/15592294.2018.1514239] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Hepatocellular carcinomas (HCCs) contain a sub-population of cancer stem cells (CSCs) that are responsible for tumor relapse, metastasis, and chemoresistance. We recently showed that loss of macroH2A1, a variant of the histone H2A and an epigenetic regulator of stem-cell function, in HCC leads to CSC-like features such as resistance to chemotherapeutic agents and growth of large and relatively undifferentiated tumors in xenograft models. These HCC cells silenced for macroH2A1 also exhibited stem-like metabolic changes consistent with enhanced glycolysis. However, there is no consensus as to the metabolic characteristics of CSCs that render them adaptable to microenvironmental changes by conveniently shifting energy production source or by acquiring intermediate metabolic phenotypes. Here, we assessed long-term proliferation, energy metabolism, and central carbon metabolism in human hepatoma HepG2 cells depleted in macroH2A1. MacroH2A1-depleted HepG2 cells were insensitive to serum exhaustion and showed two distinct, but interdependent changes in glucose and lipid metabolism in CSCs: (1) massive upregulation of acetyl-coA that is transformed into enhanced lipid content and (2) increased activation of the pentose phosphate pathway, diverting glycolytic intermediates to provide precursors for nucleotide synthesis. Integration of metabolomic analyses with RNA-Seq data revealed a critical role for the Liver X Receptor pathway, whose inhibition resulted in attenuated CSCs-like features. These findings shed light on the metabolic phenotype of epigenetically modified CSC-like hepatic cells, and highlight a potential approach for selective therapeutic targeting.
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Affiliation(s)
- Oriana Lo Re
- a Center for Translational Medicine, International Clinical Research Center , St'Anne University Hospital , Brno , Czech Republic.,b Department of Biology, Faculty of Medicine , Masaryk University , Brno , Czech Republic
| | - Julien Douet
- d Josep Carreras Leukemia Research Institute (IJC), Campus ICO-Germans Trias I Pujol , Universitat Autònoma de Barcelona , Badalona , Spain.,e Programme of Predictive and Personalized Medicine of Cancer , Germans Trias i Pujol Research Institute (PMPPC-IGTP) , Badalona , Spain
| | - Marcus Buschbeck
- d Josep Carreras Leukemia Research Institute (IJC), Campus ICO-Germans Trias I Pujol , Universitat Autònoma de Barcelona , Badalona , Spain.,e Programme of Predictive and Personalized Medicine of Cancer , Germans Trias i Pujol Research Institute (PMPPC-IGTP) , Badalona , Spain
| | - Caterina Fusilli
- c IRCCS Casa Sollievo della Sofferenza , UO of Bioinformatics , San Giovanni Rotondo , Italy
| | - Valerio Pazienza
- f Gastroenterology unit , IRCCS Casa Sollievo della Sofferenza , San Giovanni Rotondo , Italy
| | - Concetta Panebianco
- f Gastroenterology unit , IRCCS Casa Sollievo della Sofferenza , San Giovanni Rotondo , Italy
| | | | - Tommaso Mazza
- c IRCCS Casa Sollievo della Sofferenza , UO of Bioinformatics , San Giovanni Rotondo , Italy
| | - Giovanni Li Volti
- g Department of Biomedical and Biotechnological Sciences , University of Catania , Catania , Italy
| | - Manlio Vinciguerra
- a Center for Translational Medicine, International Clinical Research Center , St'Anne University Hospital , Brno , Czech Republic.,h Institute for Liver and Digestive Health, Division of Medicine , University College London (UCL) , London , UK
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28
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Kozlowski M, Corujo D, Hothorn M, Guberovic I, Mandemaker IK, Blessing C, Sporn J, Gutierrez-Triana A, Smith R, Portmann T, Treier M, Scheffzek K, Huet S, Timinszky G, Buschbeck M, Ladurner AG. MacroH2A histone variants limit chromatin plasticity through two distinct mechanisms. EMBO Rep 2018; 19:embr.201744445. [PMID: 30177554 DOI: 10.15252/embr.201744445] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 08/01/2018] [Accepted: 08/02/2018] [Indexed: 01/22/2023] Open
Abstract
MacroH2A histone variants suppress tumor progression and act as epigenetic barriers to induced pluripotency. How they impart their influence on chromatin plasticity is not well understood. Here, we analyze how the different domains of macroH2A proteins contribute to chromatin structure and dynamics. By solving the crystal structure of the macrodomain of human macroH2A2 at 1.7 Å, we find that its putative binding pocket exhibits marked structural differences compared with the macroH2A1.1 isoform, rendering macroH2A2 unable to bind ADP-ribose. Quantitative binding assays show that this specificity is conserved among vertebrate macroH2A isoforms. We further find that macroH2A histones reduce the transient, PARP1-dependent chromatin relaxation that occurs in living cells upon DNA damage through two distinct mechanisms. First, macroH2A1.1 mediates an isoform-specific effect through its ability to suppress PARP1 activity. Second, the unstructured linker region exerts an additional repressive effect that is common to all macroH2A proteins. In the absence of DNA damage, the macroH2A linker is also sufficient for rescuing heterochromatin architecture in cells deficient for macroH2A.
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Affiliation(s)
- Marek Kozlowski
- Biomedical Center, Physiological Chemistry, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - David Corujo
- Josep Carreras Leukaemia Research Institute, Campus ICO-Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain.,PhD Programme of Genetics, Universitat de Barcelona, Barcelona, Spain
| | | | - Iva Guberovic
- Josep Carreras Leukaemia Research Institute, Campus ICO-Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain
| | - Imke K Mandemaker
- Biomedical Center, Physiological Chemistry, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Charlotte Blessing
- Biomedical Center, Physiological Chemistry, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Judith Sporn
- European Molecular Biology Laboratory, Heidelberg, Germany
| | | | - Rebecca Smith
- Biomedical Center, Physiological Chemistry, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | | | - Mathias Treier
- European Molecular Biology Laboratory, Heidelberg, Germany
| | | | - Sebastien Huet
- Univ Rennes, CNRS, Structure fédérative de recherche Biosit, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, Rennes, France
| | - Gyula Timinszky
- Biomedical Center, Physiological Chemistry, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Marcus Buschbeck
- Josep Carreras Leukaemia Research Institute, Campus ICO-Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain .,Program for Predictive and Personalized Medicine of Cancer, Germans Trias i Pujol Research Institute (PMPPC-IGTP), Badalona, Spain
| | - Andreas G Ladurner
- Biomedical Center, Physiological Chemistry, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany .,Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Ludwig-Maximilians-Universität München, Munich, Germany
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29
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Haque N, Ouda R, Chen C, Ozato K, Hogg JR. ZFR coordinates crosstalk between RNA decay and transcription in innate immunity. Nat Commun 2018; 9:1145. [PMID: 29559679 PMCID: PMC5861047 DOI: 10.1038/s41467-018-03326-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 02/05/2018] [Indexed: 12/29/2022] Open
Abstract
Control of type I interferon production is crucial to combat infection while preventing deleterious inflammatory responses, but the extent of the contribution of post-transcriptional mechanisms to innate immune regulation is unclear. Here, we show that human zinc finger RNA-binding protein (ZFR) represses the interferon response by regulating alternative pre-mRNA splicing. ZFR expression is tightly controlled during macrophage development; monocytes express truncated ZFR isoforms, while macrophages induce full-length ZFR to modulate macrophage-specific alternative splicing. Interferon-stimulated genes are constitutively activated by ZFR depletion, and immunostimulation results in hyper-induction of interferon β (IFNβ/IFNB1). Through whole-genome analyses, we show that ZFR controls interferon signaling by preventing aberrant splicing and nonsense-mediated decay of histone variant macroH2A1/H2AFY mRNAs. Together, our data suggest that regulation of ZFR in macrophage differentiation guards against aberrant interferon responses and reveal a network of mRNA processing and decay that shapes the transcriptional response to infection. Type I interferon signaling is critical for the control of infection. Here the authors show that zinc finger RNA-binding protein (ZFR) can control type I interferon responses, and that this control is itself regulated by distinct ZFR truncation patterns that differ between monocytes and macrophages.
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Affiliation(s)
- Nazmul Haque
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, 50 South Drive, Room 2341, Bethesda, MD, 20892, USA.
| | - Ryota Ouda
- Division of Developmental Biology, National Institute of Child Health and Human Development, National Institutes of Health, 6 Center Drive, Room 2A01, Bethesda, MD, 20892, USA
| | - Chao Chen
- Division of Developmental Biology, National Institute of Child Health and Human Development, National Institutes of Health, 6 Center Drive, Room 2A01, Bethesda, MD, 20892, USA
| | - Keiko Ozato
- Division of Developmental Biology, National Institute of Child Health and Human Development, National Institutes of Health, 6 Center Drive, Room 2A01, Bethesda, MD, 20892, USA
| | - J Robert Hogg
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, 50 South Drive, Room 2341, Bethesda, MD, 20892, USA.
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30
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Hodge DQ, Cui J, Gamble MJ, Guo W. Histone Variant MacroH2A1 Plays an Isoform-Specific Role in Suppressing Epithelial-Mesenchymal Transition. Sci Rep 2018; 8:841. [PMID: 29339820 PMCID: PMC5770377 DOI: 10.1038/s41598-018-19364-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/27/2017] [Indexed: 02/06/2023] Open
Abstract
Epithelial-Mesenchymal Transition (EMT) is a biological program that plays key roles in various developmental and pathological processes. Although much work has been done on signaling pathways and transcription factors regulating EMT, the epigenetic regulation of EMT remains not well understood. Histone variants have been recognized as a key group of epigenetic regulators. Among them, macroH2A1 is involved in stem cell reprogramming and cancer progression. We postulated that macroH2A1 may play a role in EMT, a process involving reprogramming of cellular states. In this study, we demonstrate that expression of macroH2A1 is dramatically reduced during EMT induction in immortalized human mammary epithelial cells (HMLE). Moreover, ectopic expression of the macroH2A1.1 isoform, but not macroH2A1.2, can suppress EMT induction and reduce the stem-like cell population in HMLE. Interestingly, macroH2A1.1 overexpression cannot revert stable mesenchymal cells back to the epithelial state, suggesting a stage-specific role of macroH2A1.1 in EMT. We further pinpointed that the function of macroH2A1.1 in EMT suppression is dependent on its ability to bind the NAD+ metabolite PAR, in agreement with the inability to suppress EMT by macroH2A1.2, which lacks the PAR binding domain. Thus, our work discovered a previously unrecognized isoform-specific function of macroH2A1 in regulating EMT induction.
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Affiliation(s)
- Dayle Q Hodge
- Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Jihong Cui
- Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Matthew J Gamble
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Wenjun Guo
- Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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31
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Quénet D. Histone Variants and Disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 335:1-39. [DOI: 10.1016/bs.ircmb.2017.07.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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32
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Lo Re O, Vinciguerra M. Histone MacroH2A1: A Chromatin Point of Intersection between Fasting, Senescence and Cellular Regeneration. Genes (Basel) 2017; 8:genes8120367. [PMID: 29206173 PMCID: PMC5748685 DOI: 10.3390/genes8120367] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 11/27/2017] [Accepted: 11/30/2017] [Indexed: 12/22/2022] Open
Abstract
Histone variants confer chromatin unique properties. They have specific genomic distribution, regulated by specific deposition and removal machineries. Histone variants, mostly of canonical histones H2A, H2B and H3, have important roles in early embryonic development, in lineage commitment of stem cells, in the converse process of somatic cell reprogramming to pluripotency and, in some cases, in the modulation of animal aging and life span. MacroH2A1 is a variant of histone H2A, present in two alternatively exon-spliced isoforms macroH2A1.1 and macroH2A1.2, regulating cell plasticity and proliferation, during pluripotency and tumorigenesis. Furthermore, macroH2A1 participates in the formation of senescence-associated heterochromatic foci (SAHF) in senescent cells, and multiple lines of evidence in genetically modified mice suggest that macroH2A1 integrates nutritional cues from the extracellular environment to transcriptional programs. Here, we review current molecular evidence based on next generation sequencing data, cell assays and in vivo models supporting different mechanisms that could mediate the function of macroH2A1 in health span and life span. We will further discuss context-dependent and isoform-specific functions. The aim of this review is to provide guidance to assess histone variant macroH2A1 potential as a therapeutic intervention point.
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Affiliation(s)
- Oriana Lo Re
- Center for Translational Medicine, International Clinical Research Center, St'Anne University Hospital, Brno 656 91, Czech Republic.
- Faculty of Medicine, Masaryk University, Brno 656 91, Czech Republic.
| | - Manlio Vinciguerra
- Center for Translational Medicine, International Clinical Research Center, St'Anne University Hospital, Brno 656 91, Czech Republic.
- Faculty of Medicine, Masaryk University, Brno 656 91, Czech Republic.
- Division of Medicine, Institute for Liver and Digestive Health, University College London (UCL), London WC1E 6BT, UK.
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33
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Cedeno RJ, Nakauka-Ddamba A, Yousefi M, Sterling S, Leu NA, Li N, Pehrson JR, Lengner CJ. The histone variant macroH2A confers functional robustness to the intestinal stem cell compartment. PLoS One 2017; 12:e0185196. [PMID: 28934364 PMCID: PMC5608326 DOI: 10.1371/journal.pone.0185196] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 09/07/2017] [Indexed: 12/20/2022] Open
Abstract
A stem cell's epigenome directs cell fate during development, homeostasis, and regeneration. Epigenetic dysregulation can lead to inappropriate cell fate decisions, aberrant cell function, and even cancer. The histone variant macroH2A has been shown to influence gene expression, guide cell fate, and safeguard against genotoxic stress. Interestingly, mice lacking functional macroH2A histones (hereafter referred to as macroH2A DKO) are viable and fertile; yet suffer from increased perinatal death and reduced weight and size compared to wildtype (WT). Here, we ask whether the ostensible reduced vigor of macroH2A DKO mice extends to intestinal stem cell (ISC) function during homeostasis, regeneration, and oncogenesis. Lgr5-eGFP-IRES-CreERT2 or Hopx-CreERT2::Rosa26-LSL-tdTomato ISC reporter mice or the C57BL/6J-Apcmin/J murine intestinal adenoma model were bred into a macroH2A DKO or strain-matched WT background and assessed for ISC functionality, regeneration and tumorigenesis. High-dose (12Gy) whole-body γ-irradiation was used as an injury model. We show that macroH2A is dispensable for intestinal homeostasis and macroH2A DKO mice have similar numbers of active crypt-base columnar ISCs (CBCs). MacroH2A DKO intestine exhibits impaired regeneration following injury, despite having significantly more putative reserve ISCs. DKO reserve ISCs disproportionately undergo apoptosis compared to WT after DNA damage infliction. Interestingly, a macroH2A DKO background does not significantly increase tumorigenesis in the Apcmin model of intestinal adenoma. We conclude that macroH2A influences reserve ISC number and function during homeostasis and regeneration. These data suggest macroH2A enhances reserve ISC survival after DNA damage and thus confers functional robustness to the intestinal epithelium.
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Affiliation(s)
- Ryan James Cedeno
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America.,Cell and Molecular Biology Graduate Program, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, United States of America
| | - Angela Nakauka-Ddamba
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America
| | - Maryam Yousefi
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America.,Cell and Molecular Biology Graduate Program, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, United States of America
| | - Stephanie Sterling
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America.,Center for Animal Transgenesis, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America
| | - Nicolae Adrian Leu
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America.,Center for Animal Transgenesis, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America
| | - Ning Li
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America
| | - John R Pehrson
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America
| | - Christopher Joachim Lengner
- Department of Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America.,Center for Animal Transgenesis, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America.,Center for Molecular Studies in Digestive and Liver Disease, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.,Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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34
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Jullien J, Vodnala M, Pasque V, Oikawa M, Miyamoto K, Allen G, David SA, Brochard V, Wang S, Bradshaw C, Koseki H, Sartorelli V, Beaujean N, Gurdon J. Gene Resistance to Transcriptional Reprogramming following Nuclear Transfer Is Directly Mediated by Multiple Chromatin-Repressive Pathways. Mol Cell 2017; 65:873-884.e8. [PMID: 28257702 PMCID: PMC5344684 DOI: 10.1016/j.molcel.2017.01.030] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 01/05/2017] [Accepted: 01/24/2017] [Indexed: 12/22/2022]
Abstract
Understanding the mechanism of resistance of genes to reactivation will help improve the success of nuclear reprogramming. Using mouse embryonic fibroblast nuclei with normal or reduced DNA methylation in combination with chromatin modifiers able to erase H3K9me3, H3K27me3, and H2AK119ub1 from transplanted nuclei, we reveal the basis for resistance of genes to transcriptional reprogramming by oocyte factors. A majority of genes is affected by more than one type of treatment, suggesting that resistance can require repression through multiple epigenetic mechanisms. We classify resistant genes according to their sensitivity to 11 chromatin modifier combinations, revealing the existence of synergistic as well as adverse effects of chromatin modifiers on removal of resistance. We further demonstrate that the chromatin modifier USP21 reduces resistance through its H2AK119 deubiquitylation activity. Finally, we provide evidence that H2A ubiquitylation also contributes to resistance to transcriptional reprogramming in mouse nuclear transfer embryos. Identification of genes resistant to direct transcriptional reprogramming Determination of resistant gene sensitivity to 11 chromatin modifier combinations USP21 removes resistance through its H2AK119 deubiquitylation activity USP21 improves the reprogramming of gene expression in two-cell-stage mouse embryos
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Affiliation(s)
- Jerome Jullien
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK.
| | - Munender Vodnala
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
| | - Vincent Pasque
- Department of Development and Regeneration, KU Leuven, University of Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Mami Oikawa
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
| | - Kei Miyamoto
- Laboratory of Molecular Developmental Biology, Graduate School of Biology-Oriented Science and Technology, Kinki University, Wakayama 649-6493, Japan
| | - George Allen
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
| | - Sarah Anne David
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy en Josas, France
| | - Vincent Brochard
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy en Josas, France
| | - Stan Wang
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK; Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), NIH, Bethesda, MD 20892, USA
| | - Charles Bradshaw
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
| | - Haruhiko Koseki
- RIKEN Center for Integrative Medical Sciences, Laboratory for Developmental Genetics, North Research Building, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama City, Kanagawa 230-0045, Japan
| | - Vittorio Sartorelli
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), NIH, Bethesda, MD 20892, USA
| | - Nathalie Beaujean
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy en Josas, France
| | - John Gurdon
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
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35
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Epigenetic regulation of somatic cell reprogramming. Curr Opin Genet Dev 2017; 46:156-163. [PMID: 28823984 DOI: 10.1016/j.gde.2017.07.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 06/22/2017] [Accepted: 07/10/2017] [Indexed: 12/16/2022]
Abstract
Pluripotent stem cells, having self-renewal capacities and multi-lineage differentiation abilities, offer great potential in disease modeling and therapeutic applications. The successful generation of induced pluripotent stem cells (iPSCs) by the Yamanaka group in 2006 is a milestone event in both reprogramming and stem cell research fields, which makes in vitro somatic cell reprogramming and personalized stem cell therapy feasible. During the past 10 years, several important progresses have been made in uncovering the molecular mechanisms involved in the reprogramming process, which shed light on improving the reprogramming efficiency and iPSC quality. Here, we briefly review the important progresses in the epigenetic regulation including histone and DNA modifications during somatic cell reprogramming.
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36
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Douet J, Corujo D, Malinverni R, Renauld J, Sansoni V, Posavec Marjanović M, Cantariño N, Valero V, Mongelard F, Bouvet P, Imhof A, Thiry M, Buschbeck M. MacroH2A histone variants maintain nuclear organization and heterochromatin architecture. J Cell Sci 2017; 130:1570-1582. [PMID: 28283545 DOI: 10.1242/jcs.199216] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 03/07/2017] [Indexed: 12/15/2022] Open
Abstract
Genetic loss-of-function studies on development, cancer and somatic cell reprogramming have suggested that the group of macroH2A histone variants might function through stabilizing the differentiated state by a yet unknown mechanism. Here, we present results demonstrating that macroH2A variants have a major function in maintaining nuclear organization and heterochromatin architecture. Specifically, we find that a substantial amount of macroH2A is associated with heterochromatic repeat sequences. We further identify macroH2A on sites of interstitial heterochromatin decorated by histone H3 trimethylated on K9 (H3K9me3). Loss of macroH2A leads to major defects in nuclear organization, including reduced nuclear circularity, disruption of nucleoli and a global loss of dense heterochromatin. Domains formed by DNA repeat sequences are disorganized, expanded and fragmented, and mildly re-expressed when depleted of macroH2A. At the molecular level, we find that macroH2A is required for the interaction of repeat sequences with the nucleostructural protein lamin B1. Taken together, our results argue that a major function of macroH2A histone variants is to link nucleosome composition to higher-order chromatin architecture.
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Affiliation(s)
- Julien Douet
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO - Germans Trias i Pujol, Campus Can Ruti, Badalona 08916, Spain
- Program of Predictive and Personalized Medicine of Cancer, Germans Trias and Pujol Research Institute (PMPPC-IGTP), Campus Can Ruti, Badalona 08916, Spain
| | - David Corujo
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO - Germans Trias i Pujol, Campus Can Ruti, Badalona 08916, Spain
- Program of Predictive and Personalized Medicine of Cancer, Germans Trias and Pujol Research Institute (PMPPC-IGTP), Campus Can Ruti, Badalona 08916, Spain
| | - Roberto Malinverni
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO - Germans Trias i Pujol, Campus Can Ruti, Badalona 08916, Spain
- Program of Predictive and Personalized Medicine of Cancer, Germans Trias and Pujol Research Institute (PMPPC-IGTP), Campus Can Ruti, Badalona 08916, Spain
| | - Justine Renauld
- Cell and tissue biology unit, GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Viola Sansoni
- BioMedical Center and Center for Integrated Protein Sciences Munich, Ludwig-Maximilians-University of Munich, Großhaderner Straße 9, Planegg-Martinsried 82152, Germany
| | - Melanija Posavec Marjanović
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO - Germans Trias i Pujol, Campus Can Ruti, Badalona 08916, Spain
| | - Neus Cantariño
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO - Germans Trias i Pujol, Campus Can Ruti, Badalona 08916, Spain
| | - Vanesa Valero
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO - Germans Trias i Pujol, Campus Can Ruti, Badalona 08916, Spain
- Program of Predictive and Personalized Medicine of Cancer, Germans Trias and Pujol Research Institute (PMPPC-IGTP), Campus Can Ruti, Badalona 08916, Spain
| | - Fabien Mongelard
- Université de Lyon, Ecole normale Supérieure de Lyon, Centre de Recherche en Cancérologie de Lyon, Cancer Cell Plasticity Department, UMR INSERM 1052 CNRS5286, Centre Léon Bérard, 69008 Lyon, France
| | - Philippe Bouvet
- Université de Lyon, Ecole normale Supérieure de Lyon, Centre de Recherche en Cancérologie de Lyon, Cancer Cell Plasticity Department, UMR INSERM 1052 CNRS5286, Centre Léon Bérard, 69008 Lyon, France
| | - Axel Imhof
- BioMedical Center and Center for Integrated Protein Sciences Munich, Ludwig-Maximilians-University of Munich, Großhaderner Straße 9, Planegg-Martinsried 82152, Germany
| | - Marc Thiry
- Cell and tissue biology unit, GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Marcus Buschbeck
- Josep Carreras Leukaemia Research Institute (IJC), Campus ICO - Germans Trias i Pujol, Campus Can Ruti, Badalona 08916, Spain
- Program of Predictive and Personalized Medicine of Cancer, Germans Trias and Pujol Research Institute (PMPPC-IGTP), Campus Can Ruti, Badalona 08916, Spain
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Fagnocchi L, Zippo A. Multiple Roles of MYC in Integrating Regulatory Networks of Pluripotent Stem Cells. Front Cell Dev Biol 2017; 5:7. [PMID: 28217689 PMCID: PMC5289991 DOI: 10.3389/fcell.2017.00007] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/20/2017] [Indexed: 12/20/2022] Open
Abstract
Pluripotent stem cells (PSCs) are defined by their self-renewal potential, which permits their unlimited propagation, and their pluripotency, being able to generate cell of the three embryonic lineages. These properties render PSCs a valuable tool for both basic and medical research. To induce and stabilize the pluripotent state, complex circuitries involving signaling pathways, transcription regulators and epigenetic mechanisms converge on a core transcriptional regulatory network of PSCs, thus determining their cell identity. Among the transcription factors, MYC represents a central hub, which modulates and integrates multiple mechanisms involved both in the maintenance of pluripotency and in cell reprogramming. Indeed, it instructs the PSC-specific cell cycle, metabolism and epigenetic landscape, contributes to limit exit from pluripotency and modulates signaling cascades affecting the PSC identity. Moreover, MYC extends its regulation on pluripotency by controlling PSC-specific non-coding RNAs. In this report, we review the MYC-controlled networks, which support the pluripotent state and discuss how their perturbation could affect cell identity. We further discuss recent finding demonstrating a central role of MYC in triggering epigenetic memory in PSCs, which depends on the establishment of a WNT-centered self-reinforcing circuit. Finally, we comment on the therapeutic implications of the role of MYC in affecting PSCs. Indeed, PSCs are used for both disease and cancer modeling and to derive cells for regenerative medicine. For these reasons, unraveling the MYC-mediated mechanism in those cells is fundamental to exploit their full potential and to identify therapeutic targets.
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Affiliation(s)
- Luca Fagnocchi
- Department of Epigenetics, Fondazione Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi" (INGM)Milan, Italy; Division of Pathology, Fondazione IRCCS Ca' Granda, Ospedale Maggiore PoliclinicoMilan, Italy
| | - Alessio Zippo
- Department of Epigenetics, Fondazione Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi" (INGM)Milan, Italy; Division of Pathology, Fondazione IRCCS Ca' Granda, Ospedale Maggiore PoliclinicoMilan, Italy
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Buschbeck M, Hake SB. Variants of core histones and their roles in cell fate decisions, development and cancer. Nat Rev Mol Cell Biol 2017; 18:299-314. [DOI: 10.1038/nrm.2016.166] [Citation(s) in RCA: 217] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Rivera-Casas C, Gonzalez-Romero R, Cheema MS, Ausió J, Eirín-López JM. The characterization of macroH2A beyond vertebrates supports an ancestral origin and conserved role for histone variants in chromatin. Epigenetics 2016; 11:415-25. [PMID: 27082816 DOI: 10.1080/15592294.2016.1172161] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Histone variants play a critical role in chromatin structure and epigenetic regulation. These "deviant" proteins have been historically considered as the evolutionary descendants of ancestral canonical histones, helping specialize the nucleosome structure during eukaryotic evolution. Such view is now challenged by 2 major observations: first, canonical histones present extremely unique features not shared with any other genes; second, histone variants are widespread across many eukaryotic groups. The present work further supports the ancestral nature of histone variants by providing the first in vivo characterization of a functional macroH2A histone (a variant long defined as a specific refinement of vertebrate chromatin) in a non-vertebrate organism (the mussel Mytilus) revealing its recruitment into heterochromatic fractions of actively proliferating tissues. Combined with in silico analyses of genomic data, these results provide evidence for the widespread presence of macroH2A in metazoan animals, as well as in the holozoan Capsaspora, supporting an evolutionary origin for this histone variant lineage before the radiation of Filozoans (including Filasterea, Choanoflagellata and Metazoa). Overall, the results presented in this work help configure a new evolutionary scenario in which histone variants, rather than modern "deviants" of canonical histones, would constitute ancient components of eukaryotic chromatin.
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Affiliation(s)
- Ciro Rivera-Casas
- a Department of Biological Sciences, Chromatin Structure and Evolution (Chromevol) Group , Florida International University , North Miami , FL , USA
| | - Rodrigo Gonzalez-Romero
- a Department of Biological Sciences, Chromatin Structure and Evolution (Chromevol) Group , Florida International University , North Miami , FL , USA
| | - Manjinder S Cheema
- b Department of Biochemistry and Microbiology , University of Victoria , Victoria , British Columbia , Canada
| | - Juan Ausió
- b Department of Biochemistry and Microbiology , University of Victoria , Victoria , British Columbia , Canada
| | - José M Eirín-López
- a Department of Biological Sciences, Chromatin Structure and Evolution (Chromevol) Group , Florida International University , North Miami , FL , USA
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Pinter SF. A Tale of Two Cities: How Xist and its partners localize to and silence the bicompartmental X. Semin Cell Dev Biol 2016; 56:19-34. [PMID: 27072488 DOI: 10.1016/j.semcdb.2016.03.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 03/30/2016] [Accepted: 03/30/2016] [Indexed: 10/22/2022]
Abstract
Sex chromosomal dosage compensation in mammals takes the form of X chromosome inactivation (XCI), driven by the non-coding RNA Xist. In contrast to dosage compensation systems of flies and worms, mammalian XCI has to restrict its function to the Xist-producing X chromosome, while leaving autosomes and active X untouched. The mechanisms behind the long-range yet cis-specific localization and silencing activities of Xist have long been enigmatic, but genomics, proteomics, super-resolution microscopy, and innovative genetic approaches have produced significant new insights in recent years. In this review, I summarize and integrate these findings with a particular focus on the redundant yet mutually reinforcing pathways that enable long-term transcriptional repression throughout the soma. This includes an exploration of concurrent epigenetic changes acting in parallel within two distinct compartments of the inactive X. I also examine how Polycomb repressive complexes 1 and 2 and macroH2A may bridge XCI establishment and maintenance. XCI is a remarkable phenomenon that operates across multiple scales, combining changes in nuclear architecture, chromosome topology, chromatin compaction, and nucleosome/nucleotide-level epigenetic cues. Learning how these pathways act in concert likely holds the answer to the riddle posed by Cattanach's and other autosomal translocations: What makes the X especially receptive to XCI?
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Affiliation(s)
- Stefan F Pinter
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, University of Connecticut Health Center, 263 Farmington Ave, Farmington, CT 06030-6403, USA.
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Xu Y, Zhang M, Li W, Zhu X, Bao X, Qin B, Hutchins AP, Esteban MA. Transcriptional Control of Somatic Cell Reprogramming. Trends Cell Biol 2016; 26:272-288. [DOI: 10.1016/j.tcb.2015.12.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 12/07/2015] [Accepted: 12/16/2015] [Indexed: 01/26/2023]
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Induced Pluripotent Stem Cells: Generation Strategy and Epigenetic Mystery behind Reprogramming. Stem Cells Int 2016; 2016:8415010. [PMID: 26880993 PMCID: PMC4736417 DOI: 10.1155/2016/8415010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/03/2015] [Accepted: 11/11/2015] [Indexed: 01/06/2023] Open
Abstract
Possessing the ability of self-renewal with immortalization and potential for differentiation into different cell types, stem cells, particularly embryonic stem cells (ESC), have attracted significant attention since their discovery. As ESC research has played an essential role in developing our understanding of the mechanisms underlying reproduction, development, and cell (de)differentiation, significant efforts have been made in the biomedical study of ESC in recent decades. However, such studies of ESC have been hampered by the ethical issues and technological challenges surrounding them, therefore dramatically inhibiting the potential applications of ESC in basic biomedical studies and clinical medicine. Induced pluripotent stem cells (iPSCs), generated from the reprogrammed somatic cells, share similar characteristics including but not limited to the morphology and growth of ESC, self-renewal, and potential differentiation into various cell types. The discovery of the iPSC, unhindered by the aforementioned limitations of ESC, introduces a viable alternative to ESC. More importantly, the applications of iPSC in the development of disease models such as neurodegenerative disorders greatly enhance our understanding of the pathogenesis of such diseases and also facilitate the development of clinical therapeutic strategies using iPSC generated from patient somatic cells to avoid an immune rejection. In this review, we highlight the advances in iPSCs generation methods as well as the mechanisms behind their reprogramming. We also discuss future perspectives for the development of iPSC generation methods with higher efficiency and safety.
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GŁADYCH M, NIJAK A, LOTA P, OLEKSIEWICZ U. Epigenetics: the guardian of pluripotency and differentiation. Turk J Biol 2016. [DOI: 10.3906/biy-1509-30] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Becker JS, Nicetto D, Zaret KS. H3K9me3-Dependent Heterochromatin: Barrier to Cell Fate Changes. Trends Genet 2015; 32:29-41. [PMID: 26675384 DOI: 10.1016/j.tig.2015.11.001] [Citation(s) in RCA: 306] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 10/30/2015] [Accepted: 11/02/2015] [Indexed: 01/26/2023]
Abstract
Establishing and maintaining cell identity depends on the proper regulation of gene expression, as specified by transcription factors and reinforced by epigenetic mechanisms. Among the epigenetic mechanisms, heterochromatin formation is crucial for the preservation of genome stability and the cell type-specific silencing of genes. The heterochromatin-associated histone mark H3K9me3, although traditionally associated with the noncoding portions of the genome, has emerged as a key player in repressing lineage-inappropriate genes and shielding them from activation by transcription factors. Here we describe the role of H3K9me3 heterochromatin in impeding the reprogramming of cell identity and the mechanisms by which H3K9me3 is reorganized during development and cell fate determination.
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Affiliation(s)
- Justin S Becker
- Institute for Regenerative Medicine, Epigenetics Program, and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Dario Nicetto
- Institute for Regenerative Medicine, Epigenetics Program, and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Epigenetics Program, and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA.
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Fu Y, Lv P, Yan G, Fan H, Cheng L, Zhang F, Dang Y, Wu H, Wen B. MacroH2A1 associates with nuclear lamina and maintains chromatin architecture in mouse liver cells. Sci Rep 2015; 5:17186. [PMID: 26603343 PMCID: PMC4658601 DOI: 10.1038/srep17186] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 10/26/2015] [Indexed: 12/26/2022] Open
Abstract
In the interphase nucleus, chromatin is organized into three-dimensional conformation to coordinate genome functions. The lamina-chromatin association is important to facilitate higher-order chromatin in mammalian cells, but its biological significances and molecular mechanisms remain poorly understood. One obstacle is that the list of lamina-associated proteins remains limited, presumably due to the inherent insolubility of lamina proteins. In this report, we identified 182 proteins associated with lamin B1 (a constitutive component of lamina) in mouse hepatocytes, by adopting virus-based proximity-dependent biotin identification. These proteins are functionally related to biological processes such as chromatin organization. As an example, we validated the association between lamin B1 and core histone macroH2A1, a histone associated with repressive chromatin. Furthermore, we mapped Lamina-associated domains (LADs) in mouse liver cells and found that boundaries of LADs are enriched for macroH2A. More interestingly, knocking-down of macroH2A1 resulted in the release of heterochromatin foci marked by histone lysine 9 trimethylation (H3K9me3) and the decondensation of global chromatin structure. However, down-regulation of lamin B1 led to redistribution of macroH2A1. Taken together, our data indicated that macroH2A1 is associated with lamina and is required to maintain chromatin architecture in mouse liver cells.
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Affiliation(s)
- Yuhua Fu
- Key Laboratory of Molecular Medicine of Ministry of Education and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Pin Lv
- Key Laboratory of Molecular Medicine of Ministry of Education and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Guoquan Yan
- Key Laboratory of Molecular Medicine of Ministry of Education and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Chemistry, Fudan University, Shanghai, 200433
| | - Hui Fan
- Key Laboratory of Molecular Medicine of Ministry of Education and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Lu Cheng
- Key Laboratory of Molecular Medicine of Ministry of Education and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Feng Zhang
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yongjun Dang
- Key Laboratory of Molecular Medicine of Ministry of Education and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Hao Wu
- Department of Biostatistics and Bioinformatics, Emory University, Atlanta, GA 30322, USA
| | - Bo Wen
- Key Laboratory of Molecular Medicine of Ministry of Education and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China
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Rraklli V, Södersten E, Nyman U, Hagey DW, Holmberg J. Elevated levels of ZAC1 disrupt neurogenesis and promote rapid in vivo reprogramming. Stem Cell Res 2015; 16:1-9. [PMID: 26610203 DOI: 10.1016/j.scr.2015.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 10/27/2015] [Accepted: 11/09/2015] [Indexed: 01/26/2023] Open
Abstract
The zinc finger transcription factor Zac1 is expressed in dividing progenitors of the nervous system with expression levels negatively controlled by genomic imprinting. To explore the consequences of elevated ZAC1 levels during neurogenesis we overexpressed it in the developing CNS. Increased levels of ZAC1 rapidly promoted upregulation of CDK inhibitors P57 and P27 followed by cell cycle exit. Surprisingly this was accompanied by stalled neuronal differentiation. Genome wide expression analysis of cortical cells overexpressing Zac1 revealed a decrease in neuronal gene expression and an increased expression of imprinted genes, factors regulating mesoderm formation as well as features of differentiated muscle. In addition, we observed a rapid induction of several genes regulating pluripotency. Taken together, our data suggests that expression levels of Zac1 need to be kept under strict control to avoid premature cell cycle exit, disrupted neurogenesis and aberrant expression of non-neuronal genes including pluripotency associated factors.
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Affiliation(s)
- Vilma Rraklli
- Department of Cell and Molecular Biology, Ludwig Institute for Cancer Research, Karolinska Institutet, Nobels väg 3, 171 77, Stockholm, Sweden
| | - Erik Södersten
- Department of Cell and Molecular Biology, Ludwig Institute for Cancer Research, Karolinska Institutet, Nobels väg 3, 171 77, Stockholm, Sweden
| | - Ulrika Nyman
- Department of Cell and Molecular Biology, Ludwig Institute for Cancer Research, Karolinska Institutet, Nobels väg 3, 171 77, Stockholm, Sweden
| | - Daniel W Hagey
- Department of Cell and Molecular Biology, Ludwig Institute for Cancer Research, Karolinska Institutet, Nobels väg 3, 171 77, Stockholm, Sweden
| | - Johan Holmberg
- Department of Cell and Molecular Biology, Ludwig Institute for Cancer Research, Karolinska Institutet, Nobels väg 3, 171 77, Stockholm, Sweden.
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Pasque V, Plath K. X chromosome reactivation in reprogramming and in development. Curr Opin Cell Biol 2015; 37:75-83. [PMID: 26540406 DOI: 10.1016/j.ceb.2015.10.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 10/12/2015] [Accepted: 10/14/2015] [Indexed: 11/29/2022]
Abstract
Dramatic epigenetic changes take place during mammalian differentiation from the naïve pluripotent state including the silencing of one of the two X chromosomes in female cells through X chromosome inactivation. Conversely, reprogramming of somatic cells to naive pluripotency is coupled to X chromosome reactivation (XCR). Recent studies in the mouse system have shed light on the mechanisms of XCR by uncovering the timing and steps of XCR during reprogramming to induced pluripotent stem cells (iPSCs), allowing the generation of testable hypotheses during embryogenesis. In contrast, analyses of the X chromosome in human iPSCs have revealed important differences between mouse and human reprogramming processes that can partially be explained by the establishment of distinct pluripotent states and impact disease modeling and the application of human pluripotent stem cells. Here, we review recent literature on XCR as a readout and determinant of reprogramming to pluripotency.
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Affiliation(s)
- Vincent Pasque
- Department of Biological Chemistry, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Kathrin Plath
- Department of Biological Chemistry, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA.
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Ebrahimi B. Reprogramming barriers and enhancers: strategies to enhance the efficiency and kinetics of induced pluripotency. CELL REGENERATION (LONDON, ENGLAND) 2015; 4:10. [PMID: 26566431 PMCID: PMC4642739 DOI: 10.1186/s13619-015-0024-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 09/19/2015] [Indexed: 12/13/2022]
Abstract
Induced pluripotent stem cells are powerful tools for disease modeling, drug screening, and cell transplantation therapies. These cells can be generated directly from somatic cells by ectopic expression of defined factors through a reprogramming process. However, pluripotent reprogramming is an inefficient process because of various defined and unidentified barriers. Recent studies dissecting the molecular mechanisms of reprogramming have methodically improved the quality, ease, and efficiency of reprogramming. Different strategies have been applied for enhancing reprogramming efficiency, including depletion/inhibition of barriers (p53, p21, p57, p16(Ink4a)/p19(Arf), Mbd3, etc.), overexpression of enhancing genes (e.g., FOXH1, C/EBP alpha, UTF1, and GLIS1), and administration of certain cytokines and small molecules. The current review provides an in-depth overview of the cutting-edge findings regarding distinct barriers of reprogramming to pluripotency and strategies to enhance reprogramming efficiency. By incorporating the mechanistic insights from these recent findings, a combined method of inhibition of roadblocks and application of enhancing factors may yield the most reliable and effective approach in pluripotent reprogramming.
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Affiliation(s)
- Behnam Ebrahimi
- Yazd Cardiovascular Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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Heterochromatin Protein 1β (HP1β) has distinct functions and distinct nuclear distribution in pluripotent versus differentiated cells. Genome Biol 2015; 16:213. [PMID: 26415775 PMCID: PMC4587738 DOI: 10.1186/s13059-015-0760-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Accepted: 08/25/2015] [Indexed: 11/22/2022] Open
Abstract
Background Pluripotent embryonic stem cells (ESCs) have the unique ability to differentiate into every cell type and to self-renew. These characteristics correlate with a distinct nuclear architecture, epigenetic signatures enriched for active chromatin marks and hyperdynamic binding of structural chromatin proteins. Recently, several chromatin-related proteins have been shown to regulate ESC pluripotency and/or differentiation, yet the role of the major heterochromatin proteins in pluripotency is unknown. Results Here we identify Heterochromatin Protein 1β (HP1β) as an essential protein for proper differentiation, and, unexpectedly, for the maintenance of pluripotency in ESCs. In pluripotent and differentiated cells HP1β is differentially localized and differentially associated with chromatin. Deletion of HP1β, but not HP1α, in ESCs provokes a loss of the morphological and proliferative characteristics of embryonic pluripotent cells, reduces expression of pluripotency factors and causes aberrant differentiation. However, in differentiated cells, loss of HP1β has the opposite effect, perturbing maintenance of the differentiation state and facilitating reprogramming to an induced pluripotent state. Microscopy, biochemical fractionation and chromatin immunoprecipitation reveal a diffuse nucleoplasmic distribution, weak association with chromatin and high expression levels for HP1β in ESCs. The minor fraction of HP1β that is chromatin-bound in ESCs is enriched within exons, unlike the situation in differentiated cells, where it binds heterochromatic satellite repeats and chromocenters. Conclusions We demonstrate an unexpected duality in the role of HP1β: it is essential in ESCs for maintaining pluripotency, while it is required for proper differentiation in differentiated cells. Thus, HP1β function both depends on, and regulates, the pluripotent state. Electronic supplementary material The online version of this article (doi:10.1186/s13059-015-0760-8) contains supplementary material, which is available to authorized users.
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