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Kikuchi M, Morita S, Wakamori M, Sato S, Uchikubo-Kamo T, Suzuki T, Dohmae N, Shirouzu M, Umehara T. Epigenetic mechanisms to propagate histone acetylation by p300/CBP. Nat Commun 2023; 14:4103. [PMID: 37460559 DOI: 10.1038/s41467-023-39735-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 06/26/2023] [Indexed: 07/20/2023] Open
Abstract
Histone acetylation is important for the activation of gene transcription but little is known about its direct read/write mechanisms. Here, we report cryogenic electron microscopy structures in which a p300/CREB-binding protein (CBP) multidomain monomer recognizes histone H4 N-terminal tail (NT) acetylation (ac) in a nucleosome and acetylates non-H4 histone NTs within the same nucleosome. p300/CBP not only recognized H4NTac via the bromodomain pocket responsible for reading, but also interacted with the DNA minor grooves via the outside of that pocket. This directed the catalytic center of p300/CBP to one of the non-H4 histone NTs. The primary target that p300 writes by reading H4NTac was H2BNT, and H2BNTac promoted H2A-H2B dissociation from the nucleosome. We propose a model in which p300/CBP replicates histone N-terminal tail acetylation within the H3-H4 tetramer to inherit epigenetic storage, and transcribes it from the H3-H4 tetramer to the H2B-H2A dimers to activate context-dependent gene transcription through local nucleosome destabilization.
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Affiliation(s)
- Masaki Kikuchi
- Laboratory for Epigenetics Drug Discovery, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Satoshi Morita
- Laboratory for Epigenetics Drug Discovery, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Masatoshi Wakamori
- Laboratory for Epigenetics Drug Discovery, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Shin Sato
- Laboratory for Epigenetics Drug Discovery, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Tomomi Uchikubo-Kamo
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Takehiro Suzuki
- Biomolecular Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Naoshi Dohmae
- Biomolecular Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Mikako Shirouzu
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Takashi Umehara
- Laboratory for Epigenetics Drug Discovery, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan.
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Shahraki K, Shahraki K, Ghasemi Boroumand P, Sheervalilou R. Promotor methylation in ocular surface squamous neoplasia development: epigenetics implications in molecular diagnosis. Expert Rev Mol Diagn 2023; 23:753-769. [PMID: 37493058 DOI: 10.1080/14737159.2023.2240238] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 07/20/2023] [Indexed: 07/27/2023]
Abstract
INTRODUCTION Cancer is heavily influenced by epigenetic mechanisms that include DNA methylation, histone modifications, and non-coding RNA. A considerable proportion of human malignancies are believed to be associated with global DNA hypomethylation, with localized hypermethylation at promoters of certain genes. AREA COVERED The present review aims to emphasize on recent investigations on the epigenetic landscape of ocular surface squamous neoplasia, that could be targeted/explored using novel approaches such as personalized medicine. EXPERT OPINION While the former is thought to contribute to genomic instability, promoter-specific hypermethylation might facilitate tumorigenesis by silencing tumor suppressor genes. Ocular surface squamous neoplasia, the most prevalent type of ocular surface malignancy, is suggested to be affected by epigenetic mechanisms, as well. Although the exact role of epigenetics in ocular surface squamous neoplasia has mostly been unexplored, recent findings have greatly contributed to our understanding regarding this pathology of the eye.
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Affiliation(s)
- Kourosh Shahraki
- Ocular Tissue Engineering Research Center, Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Ophthalmology, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Kianoush Shahraki
- Department of Ophthalmology, Zahedan University of Medical Sciences, Zahedan, Iran
- Cornea Department, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Paria Ghasemi Boroumand
- ENT, Head and Neck Research Center and Department, Iran University of Medical Science, Tehran, Iran
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3
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Du W, Shi G, Shan CM, Li Z, Zhu B, Jia S, Li Q, Zhang Z. Mechanisms of chromatin-based epigenetic inheritance. SCIENCE CHINA. LIFE SCIENCES 2022; 65:2162-2190. [PMID: 35792957 PMCID: PMC10311375 DOI: 10.1007/s11427-022-2120-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/27/2022] [Indexed: 06/15/2023]
Abstract
Multi-cellular organisms such as humans contain hundreds of cell types that share the same genetic information (DNA sequences), and yet have different cellular traits and functions. While how genetic information is passed through generations has been extensively characterized, it remains largely obscure how epigenetic information encoded by chromatin regulates the passage of certain traits, gene expression states and cell identity during mitotic cell divisions, and even through meiosis. In this review, we will summarize the recent advances on molecular mechanisms of epigenetic inheritance, discuss the potential impacts of epigenetic inheritance during normal development and in some disease conditions, and outline future research directions for this challenging, but exciting field.
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Affiliation(s)
- Wenlong Du
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Guojun Shi
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Chun-Min Shan
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Zhiming Li
- Institutes of Cancer Genetics, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY, 10032, USA
| | - Bing Zhu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Songtao Jia
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA.
| | - Qing Li
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
| | - Zhiguo Zhang
- Institutes of Cancer Genetics, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY, 10032, USA.
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4
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Sump B, Brickner J. Establishment and inheritance of epigenetic transcriptional memory. Front Mol Biosci 2022; 9:977653. [PMID: 36120540 PMCID: PMC9479176 DOI: 10.3389/fmolb.2022.977653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 07/29/2022] [Indexed: 11/13/2022] Open
Abstract
For certain inducible genes, the rate and molecular mechanism of transcriptional activation depends on the prior experiences of the cell. This phenomenon, called epigenetic transcriptional memory, accelerates reactivation and requires both changes in chromatin structure and recruitment of poised RNA Polymerase II (RNAPII) to the promoter. Forms of epigenetic transcriptional memory have been identified in S. cerevisiae, D. melanogaster, C. elegans, and mammals. A well-characterized model of memory is found in budding yeast where memory of inositol starvation involves a positive feedback loop between gene-and condition-specific transcription factors, which mediate an interaction with the nuclear pore complex and a characteristic histone modification: histone H3 lysine 4 dimethylation (H3K4me2). This histone modification permits recruitment of a memory-specific pre-initiation complex, poising RNAPII at the promoter. During memory, H3K4me2 is essential for recruitment of RNAPII and faster reactivation, but RNAPII is not required for H3K4me2. Unlike the RNAPII-dependent H3K4me2 associated with active transcription, RNAPII-independent H3K4me2 requires Nup100, SET3C, the Leo1 subunit of the Paf1 complex and can be inherited through multiple cell cycles upon disrupting the interaction with the Nuclear Pore Complex. The H3K4 methyltransferase (COMPASS) physically interacts with the potential reader (SET3C), suggesting a molecular mechanism for the spreading and re-incorporation of H3K4me2 following DNA replication. Thus, epigenetic transcriptional memory is a conserved adaptation that utilizes a heritable chromatin state, allowing cells and organisms to alter their gene expression programs in response to recent experiences over intermediate time scales.
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5
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Mitotic drive in asymmetric epigenetic inheritance. Biochem Soc Trans 2022; 50:675-688. [PMID: 35437581 PMCID: PMC9162470 DOI: 10.1042/bst20200267] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 01/14/2023]
Abstract
Asymmetric cell division (ACD) produces two daughter cells with distinct cell fates. This division mode is widely used during development and by adult stem cells during tissue homeostasis and regeneration, which can be regulated by both extrinsic cues such as signaling molecules and intrinsic factors such as epigenetic information. While the DNA replication process ensures that the sequences of sister chromatids are identical, how epigenetic information is re-distributed during ACD has remained largely unclear in multicellular organisms. Studies of Drosophila male germline stem cells (GSCs) have revealed that sister chromatids incorporate pre-existing and newly synthesized histones differentially and segregate asymmetrically during ACD. To understand the underlying molecular mechanisms of this phenomenon, two key questions must be answered: first, how and when asymmetric histone information is established; and second, how epigenetically distinct sister chromatids are distinguished and segregated. Here, we discuss recent advances which help our understanding of this interesting and important cell division mode.
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Haider M, Elsherbeny A, Pittalà V, Consoli V, Alghamdi MA, Hussain Z, Khoder G, Greish K. Nanomedicine Strategies for Management of Drug Resistance in Lung Cancer. Int J Mol Sci 2022; 23:1853. [PMID: 35163777 PMCID: PMC8836587 DOI: 10.3390/ijms23031853] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/01/2022] [Accepted: 02/01/2022] [Indexed: 12/12/2022] Open
Abstract
Lung cancer (LC) is one of the leading causes of cancer occurrence and mortality worldwide. Treatment of patients with advanced and metastatic LC presents a significant challenge, as malignant cells use different mechanisms to resist chemotherapy. Drug resistance (DR) is a complex process that occurs due to a variety of genetic and acquired factors. Identifying the mechanisms underlying DR in LC patients and possible therapeutic alternatives for more efficient therapy is a central goal of LC research. Advances in nanotechnology resulted in the development of targeted and multifunctional nanoscale drug constructs. The possible modulation of the components of nanomedicine, their surface functionalization, and the encapsulation of various active therapeutics provide promising tools to bypass crucial biological barriers. These attributes enhance the delivery of multiple therapeutic agents directly to the tumor microenvironment (TME), resulting in reversal of LC resistance to anticancer treatment. This review provides a broad framework for understanding the different molecular mechanisms of DR in lung cancer, presents novel nanomedicine therapeutics aimed at improving the efficacy of treatment of various forms of resistant LC; outlines current challenges in using nanotechnology for reversing DR; and discusses the future directions for the clinical application of nanomedicine in the management of LC resistance.
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Affiliation(s)
- Mohamed Haider
- Department of Pharmaceutics and Pharmaceutical Technology, College of Pharmacy, University of Sharjah, Sharjah 27272, United Arab Emirates; (Z.H.); (G.K.)
| | - Amr Elsherbeny
- Division of Molecular Therapeutics and Formulation, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, UK;
| | - Valeria Pittalà
- Department of Drug and Health Science, University of Catania, 95125 Catania, Italy; (V.P.); (V.C.)
| | - Valeria Consoli
- Department of Drug and Health Science, University of Catania, 95125 Catania, Italy; (V.P.); (V.C.)
| | - Maha Ali Alghamdi
- Department of Biotechnology, College of Science, Taif University, Taif 21974, Saudi Arabia;
- Department of Molecular Medicine, Princess Al-Jawhara Centre for Molecular Medicine, School of Medicine and Medical Sciences, Arabian Gulf University, Manama 329, Bahrain;
| | - Zahid Hussain
- Department of Pharmaceutics and Pharmaceutical Technology, College of Pharmacy, University of Sharjah, Sharjah 27272, United Arab Emirates; (Z.H.); (G.K.)
| | - Ghalia Khoder
- Department of Pharmaceutics and Pharmaceutical Technology, College of Pharmacy, University of Sharjah, Sharjah 27272, United Arab Emirates; (Z.H.); (G.K.)
| | - Khaled Greish
- Department of Molecular Medicine, Princess Al-Jawhara Centre for Molecular Medicine, School of Medicine and Medical Sciences, Arabian Gulf University, Manama 329, Bahrain;
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7
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Yao Y, Wen Q, Zhang T, Yu C, Chan KM, Gan H. Advances in Approaches to Study Chromatin-Mediated Epigenetic Memory. ACS Synth Biol 2022; 11:16-25. [PMID: 34965084 DOI: 10.1021/acssynbio.1c00394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chromatin structure contains critical epigenetic information in various forms, such as histone post-translational modifications (PTMs). The deposition of certain histone PTMs can remodel the chromatin structure, resulting in gene expression alteration. The epigenetic information carried by histone PTMs could be inherited by daughter cells to maintain the gene expression status. Recently, studies revealed that several conserved replisome proteins regulate the recycling of parental histones carrying epigenetic information in Saccharomyces cerevisiae. Hence, the proper recycling and deposition of parental histones onto newly synthesized DNA strands is presumed to be essential for epigenetic inheritance. Here, we first reviewed the fundamental mechanisms of epigenetic modification establishment and maintenance discovered within fungal models. Next, we discussed the functions of parental histone chaperones and the potential impacts of the parental histone recycling process on heterochromatin-mediated transcriptional silencing inheritance. Subsequently, we summarized novel synthetic biology approaches developed to analyze individual epigenetic components during epigenetic inheritance in fungal and mammalian systems. These newly emerged research paradigms enable us to dissect epigenetic systems in a bottom-up manner. Furthermore, we highlighted the approaches developed in this emerging field and discussed the potential applications of these engineered regulators to building synthetic epigenetic systems.
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Affiliation(s)
- Yuan Yao
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Qing Wen
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Tianjun Zhang
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Chuanhe Yu
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
| | - Kui Ming Chan
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR 999077, China
- Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518172, China
| | - Haiyun Gan
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
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8
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Vigneau J, Borg M. The epigenetic origin of life history transitions in plants and algae. PLANT REPRODUCTION 2021; 34:267-285. [PMID: 34236522 PMCID: PMC8566409 DOI: 10.1007/s00497-021-00422-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 06/14/2021] [Indexed: 05/17/2023]
Abstract
Plants and algae have a complex life history that transitions between distinct life forms called the sporophyte and the gametophyte. This phenomenon-called the alternation of generations-has fascinated botanists and phycologists for over 170 years. Despite the mesmerizing array of life histories described in plants and algae, we are only now beginning to learn about the molecular mechanisms controlling them and how they evolved. Epigenetic silencing plays an essential role in regulating gene expression during multicellular development in eukaryotes, raising questions about its impact on the life history strategy of plants and algae. Here, we trace the origin and function of epigenetic mechanisms across the plant kingdom, from unicellular green algae through to angiosperms, and attempt to reconstruct the evolutionary steps that influenced life history transitions during plant evolution. Central to this evolutionary scenario is the adaption of epigenetic silencing from a mechanism of genome defense to the repression and control of alternating generations. We extend our discussion beyond the green lineage and highlight the peculiar case of the brown algae. Unlike their unicellular diatom relatives, brown algae lack epigenetic silencing pathways common to animals and plants yet display complex life histories, hinting at the emergence of novel life history controls during stramenopile evolution.
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Affiliation(s)
- Jérômine Vigneau
- Department of Algal Development and Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Michael Borg
- Department of Algal Development and Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany.
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9
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The regulation mechanisms and the Lamarckian inheritance property of DNA methylation in animals. Mamm Genome 2021; 32:135-152. [PMID: 33860357 DOI: 10.1007/s00335-021-09870-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 04/05/2021] [Indexed: 12/19/2022]
Abstract
DNA methylation is a stable and heritable epigenetic mechanism, of which the main functions are stabilizing the transcription of genes and promoting genetic conservation. In animals, the direct molecular inducers of DNA methylation mainly include histone covalent modification and non-coding RNA, whereas the fundamental regulators of DNA methylation are genetic and environmental factors. As is well known, competition is present everywhere in life systems, and will finally strike a balance that is optimal for the animal's survival and reproduction. The same goes for the regulation of DNA methylation. Genetic and environmental factors, respectively, are responsible for the programmed and plasticity changes of DNA methylation, and keen competition exists between genetically influenced procedural remodeling and environmentally influenced plastic alteration. In this process, genetic and environmental factors collaboratively decide the methylation patterns of corresponding loci. DNA methylation alterations induced by environmental factors can be transgenerationally inherited, and exhibit the characteristic of Lamarckian inheritance. Further research on regulatory mechanisms and the environmental plasticity of DNA methylation will provide strong support for understanding the biological function and evolutionary effects of DNA methylation.
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10
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Jiang S, Postovit L, Cattaneo A, Binder EB, Aitchison KJ. Epigenetic Modifications in Stress Response Genes Associated With Childhood Trauma. Front Psychiatry 2019; 10:808. [PMID: 31780969 PMCID: PMC6857662 DOI: 10.3389/fpsyt.2019.00808] [Citation(s) in RCA: 117] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 10/11/2019] [Indexed: 12/12/2022] Open
Abstract
Adverse childhood experiences (ACEs) may be referred to by other terms (e.g., early life adversity or stress and childhood trauma) and have a lifelong impact on mental and physical health. For example, childhood trauma has been associated with posttraumatic stress disorder (PTSD), anxiety, depression, bipolar disorder, diabetes, and cardiovascular disease. The heritability of ACE-related phenotypes such as PTSD, depression, and resilience is low to moderate, and, moreover, is very variable for a given phenotype, which implies that gene by environment interactions (such as through epigenetic modifications) may be involved in the onset of these phenotypes. Currently, there is increasing interest in the investigation of epigenetic contributions to ACE-induced differential health outcomes. Although there are a number of studies in this field, there are still research gaps. In this review, the basic concepts of epigenetic modifications (such as methylation) and the function of the hypothalamic-pituitary-adrenal (HPA) axis in the stress response are outlined. Examples of specific genes undergoing methylation in association with ACE-induced differential health outcomes are provided. Limitations in this field, e.g., uncertain clinical diagnosis, conceptual inconsistencies, and technical drawbacks, are reviewed, with suggestions for advances using new technologies and novel research directions. We thereby provide a platform on which the field of ACE-induced phenotypes in mental health may build.
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Affiliation(s)
- Shui Jiang
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - Lynne Postovit
- Department of Oncology, University of Alberta, Edmonton, AB, Canada
| | - Annamaria Cattaneo
- Biological Psychiatric Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Elisabeth B. Binder
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Munich, Germany
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, United States
| | - Katherine J. Aitchison
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
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Roberti A, Valdes AF, Torrecillas R, Fraga MF, Fernandez AF. Epigenetics in cancer therapy and nanomedicine. Clin Epigenetics 2019; 11:81. [PMID: 31097014 PMCID: PMC6524244 DOI: 10.1186/s13148-019-0675-4] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/29/2019] [Indexed: 12/21/2022] Open
Abstract
The emergence of nanotechnology applied to medicine has revolutionized the treatment of human cancer. As in the case of classic drugs for the treatment of cancer, epigenetic drugs have evolved in terms of their specificity and efficiency, especially because of the possibility of using more effective transport and delivery systems. The use of nanoparticles (NPs) in oncology management offers promising advantages in terms of the efficacy of cancer treatments, but it is still unclear how these NPs may be affecting the epigenome such that safe routine use is ensured. In this work, we summarize the importance of the epigenetic alterations identified in human cancer, which have led to the appearance of biomarkers or epigenetic drugs in precision medicine, and we describe the transport and release systems of the epigenetic drugs that have been developed to date.
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Affiliation(s)
- Annalisa Roberti
- Cancer Epigenetics Laboratory, Institute of Oncology of Asturias (IUOPA), ISPA-FINBA-Hospital Universitario Central de Asturias HUCA, Universidad de Oviedo, Avenida de Roma, 33011, Oviedo, Asturias, Spain
| | - Adolfo F Valdes
- Nanomaterials and Nanotechnology Research Center (CINN-CSIC)-Universidad de Oviedo-Principado de Asturias, Avenida de Roma, 33011, Oviedo, Asturias, Spain
| | - Ramón Torrecillas
- Nanomaterials and Nanotechnology Research Center (CINN-CSIC)-Universidad de Oviedo-Principado de Asturias, Avenida de Roma, 33011, Oviedo, Asturias, Spain
| | - Mario F Fraga
- Nanomaterials and Nanotechnology Research Center (CINN-CSIC)-Universidad de Oviedo-Principado de Asturias, Avenida de Roma, 33011, Oviedo, Asturias, Spain.
| | - Agustin F Fernandez
- Cancer Epigenetics Laboratory, Institute of Oncology of Asturias (IUOPA), ISPA-FINBA-Hospital Universitario Central de Asturias HUCA, Universidad de Oviedo, Avenida de Roma, 33011, Oviedo, Asturias, Spain.
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12
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Primers on nutrigenetics and nutri(epi)genomics: Origins and development of precision nutrition. Biochimie 2019; 160:156-171. [PMID: 30878492 DOI: 10.1016/j.biochi.2019.03.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 03/08/2019] [Indexed: 12/11/2022]
Abstract
Understanding the relationship between genotype and phenotype is a central goal not just for genetics but also for medicine and biological sciences. Despite outstanding technological progresses, genetics alone is not able to completely explain phenotypes, in particular for complex diseases. Given the existence of a "missing heritability", growing attention has been given to non-mendelian mechanisms of inheritance and to the role of the environment. The study of interaction between gene and environment represents a challenging but also a promising field with high potential for health prevention, and epigenetics has been suggested as one of the best candidate to mediate environmental effects on the genome. Among environmental factors able to interact with both genome and epigenome, nutrition is one of the most impacting. Not just our genome influences the responsiveness to food and nutrients, but vice versa, nutrition can also modify gene expression through epigenetic mechanisms. In this complex picture, nutrigenetics and nutrigenomics represent appealing disciplines aimed to define new prospectives of personalized nutrition. This review introduces to the study of gene-environment interactions and describes how nutrigenetics and nutrigenomics modulate health, promoting or affecting healthiness through life-style, thus playing a pivotal role in modulating the effect of genetic predispositions.
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Lu M, He X. Ccp1 modulates epigenetic stability at centromeres and affects heterochromatin distribution in Schizosaccharomyces pombe. J Biol Chem 2018; 293:12068-12080. [PMID: 29899117 PMCID: PMC6078436 DOI: 10.1074/jbc.ra118.003873] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/02/2018] [Indexed: 12/26/2022] Open
Abstract
Distinct chromatin organization features, such as centromeres and heterochromatin domains, are inherited epigenetically. However, the mechanisms that modulate the accuracy of epigenetic inheritance, especially at the individual nucleosome level, are not well-understood. Here, using ChIP and next-generation sequencing (ChIP-Seq), we characterized Ccp1, a homolog of the histone chaperone Vps75 in budding yeast that functions in centromere chromatin duplication and heterochromatin maintenance in fission yeast (Schizosaccharomyces pombe). We show that Ccp1 is enriched at the central core regions of the centromeres. Of note, among all histone chaperones characterized, deletion of the ccp1 gene uniquely reduced the rate of epigenetic switching, manifested as position effect variegation within the centromeric core region (CEN-PEV). In contrast, gene deletion of other histone chaperones either elevated the PEV switching rates or did not affect centromeric PEV. Ccp1 and the kinetochore components Mis6 and Sim4 were mutually dependent for centromere or kinetochore association at the proper levels. Moreover, Ccp1 influenced heterochromatin distribution at multiple loci in the genome, including the subtelomeric and the pericentromeric regions. We also found that Gar2, a protein predominantly enriched in the nucleolus, functions similarly to Ccp1 in modulating the epigenetic stability of centromeric regions, although its mechanism remained unclear. Together, our results identify Ccp1 as an important player in modulating epigenetic stability and maintaining proper organization of multiple chromatin domains throughout the fission yeast genome.
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Affiliation(s)
- Min Lu
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiangwei He
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou, Zhejiang 310058, China.
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Cheung P, Vallania F, Warsinske HC, Donato M, Schaffert S, Chang SE, Dvorak M, Dekker CL, Davis MM, Utz PJ, Khatri P, Kuo AJ. Single-Cell Chromatin Modification Profiling Reveals Increased Epigenetic Variations with Aging. Cell 2018; 173:1385-1397.e14. [PMID: 29706550 PMCID: PMC5984186 DOI: 10.1016/j.cell.2018.03.079] [Citation(s) in RCA: 216] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 02/27/2018] [Accepted: 03/28/2018] [Indexed: 12/17/2022]
Abstract
Post-translational modifications of histone proteins and exchanges of histone variants of chromatin are central to the regulation of nearly all DNA-templated biological processes. However, the degree and variability of chromatin modifications in specific human immune cells remain largely unknown. Here, we employ a highly multiplexed mass cytometry analysis to profile the global levels of a broad array of chromatin modifications in primary human immune cells at the single-cell level. Our data reveal markedly different cell-type- and hematopoietic-lineage-specific chromatin modification patterns. Differential analysis between younger and older adults shows that aging is associated with increased heterogeneity between individuals and elevated cell-to-cell variability in chromatin modifications. Analysis of a twin cohort unveils heritability of chromatin modifications and demonstrates that aging-related chromatin alterations are predominantly driven by non-heritable influences. Together, we present a powerful platform for chromatin and immunology research. Our discoveries highlight the profound impacts of aging on chromatin modifications.
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Affiliation(s)
- Peggie Cheung
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Francesco Vallania
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Hayley C Warsinske
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Michele Donato
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Steven Schaffert
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sarah E Chang
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Mai Dvorak
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Cornelia L Dekker
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Mark M Davis
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94304, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Paul J Utz
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Purvesh Khatri
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Alex J Kuo
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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15
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Tikhodeyev ON. The mechanisms of epigenetic inheritance: how diverse are they? Biol Rev Camb Philos Soc 2018; 93:1987-2005. [PMID: 29790249 DOI: 10.1111/brv.12429] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/22/2018] [Accepted: 04/27/2018] [Indexed: 12/18/2022]
Abstract
Although epigenetic inheritance (EI) is a rapidly growing field of modern biology, it still has no clear place in fundamental genetic concepts which are traditionally based on the hereditary role of DNA. Moreover, not all mechanisms of EI attract the same attention, with most studies focused on DNA methylation, histone modification, RNA interference and amyloid prionization, but relatively few considering other mechanisms such as stable inhibition of plastid translation. Herein, we discuss all known and some hypothetical mechanisms that can underlie the stable inheritance of phenotypically distinct hereditary factors that lack differences in DNA sequence. These mechanisms include (i) regulation of transcription by DNA methylation, histone modifications, and transcription factors, (ii) RNA splicing, (iii) RNA-mediated post-transcriptional silencing, (iv) organellar translation, (v) protein processing by truncation, (vi) post-translational chemical modifications, (vii) protein folding, and (viii) homologous and non-homologous protein interactions. The breadth of this list suggests that any or almost any regulatory mechanism that participates in gene expression or gene-product functioning, under certain circumstances, may produce EI. Although the modes of EI are highly variable, in many epigenetic systems, stable allelic variants can be distinguished. Irrespective of their nature, all such alleles have an underlying similarity: each is a bimodular hereditary unit, whose features depend on (i) a certain epigenetic mark (epigenetic determinant) in the DNA sequence or its product, and (ii) the DNA sequence itself (DNA determinant; if this is absent, the epigenetic allele fails to perpetuate). Thus, stable allelic epigenetic inheritance (SAEI) does not contradict the hereditary role of DNA, but involves additional molecular mechanisms with no or almost no limitations to their variety.
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Affiliation(s)
- Oleg N Tikhodeyev
- Department of Genetics & Biotechnology, Saint-Petersburg State University, Saint-Petersburg 199034, Russia
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16
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Liu Y, Liu S, Yuan S, Yu H, Zhang Y, Yang X, Xie G, Chen Z, Li W, Xu B, Sun L, Shang Y, Liang J. Chromodomain protein CDYL is required for transmission/restoration of repressive histone marks. J Mol Cell Biol 2018; 9:178-194. [PMID: 28402439 DOI: 10.1093/jmcb/mjx013] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 04/02/2017] [Indexed: 12/22/2022] Open
Abstract
Faithful transmission or restoration of epigenetic information such as repressive histone modifications through generations is critical for the maintenance of cell identity. We report here that chromodomain Y-like protein (CDYL), a chromodomain-containing transcription corepressor, is physically associated with chromatin assembly factor 1 (CAF-1) and the replicative helicase MCM complex. We showed that CDYL bridges CAF-1 and MCM, facilitating histone transfer and deposition during DNA replication. We demonstrated that CDYL recruits histone-modifying enzymes G9a, SETDB1, and EZH2 to replication forks, leading to the addition of H3K9me2/3 and H3K27me2/3 on newly deposited histone H3. Significantly, depletion of CDYL impedes early S phase progression and sensitizes cells to DNA damage. Our data indicate that CDYL plays an important role in the transmission/restoration of repressive histone marks, thereby preserving the epigenetic landscape for the maintenance of cell identity.
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Affiliation(s)
- Yongqing Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Shumeng Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Shuai Yuan
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Huajing Yu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Yu Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Xiaohan Yang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Guojia Xie
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Zhe Chen
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Wanjin Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Bosen Xu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Luyang Sun
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Yongfeng Shang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.,Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China.,Tianjin Key Laboratory of Medical Epigenetics, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Jing Liang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
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17
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Wang C, Zhu B, Xiong J. Recruitment and reinforcement: maintaining epigenetic silencing. SCIENCE CHINA-LIFE SCIENCES 2018; 61:515-522. [PMID: 29564598 DOI: 10.1007/s11427-018-9276-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 01/16/2018] [Indexed: 01/07/2023]
Abstract
Cells need to appropriately balance transcriptional stability and adaptability in order to maintain their identities while responding robustly to various stimuli. Eukaryotic cells use an elegant "epigenetic" system to achieve this functionality. "Epigenetics" is referred to as heritable information beyond the DNA sequence, including histone and DNA modifications, ncRNAs and other chromatin-related components. Here, we review the mechanisms of the epigenetic inheritance of a repressive chromatin state, with an emphasis on recent progress in the field. We emphasize that (i) epigenetic information is inherited in a relatively stable but imprecise fashion; (ii) multiple cis and trans factors are involved in the maintenance of epigenetic information during mitosis; and (iii) the maintenance of a repressive epigenetic state requires both recruitment and self-reinforcement mechanisms. These mechanisms crosstalk with each other and form interconnected feedback loops to shape a stable epigenetic system while maintaining certain degrees of flexibility.
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Affiliation(s)
- Chengzhi Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Bing Zhu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jun Xiong
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
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18
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Symmetry from Asymmetry or Asymmetry from Symmetry? COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2018; 82:305-318. [PMID: 29348326 DOI: 10.1101/sqb.2017.82.034272] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The processes of DNA replication and mitosis allow the genetic information of a cell to be copied and transferred reliably to its daughter cells. However, if DNA replication and cell division were always performed in a symmetric manner, the result would be a cluster of tumor cells instead of a multicellular organism. Therefore, gaining a complete understanding of any complex living organism depends on learning how cells become different while faithfully maintaining the same genetic material. It is well recognized that the distinct epigenetic information contained in each cell type defines its unique gene expression program. Nevertheless, how epigenetic information contained in the parental cell is either maintained or changed in the daughter cells remains largely unknown. During the asymmetric cell division (ACD) of Drosophila male germline stem cells, our previous work revealed that preexisting histones are selectively retained in the renewed stem cell daughter, whereas newly synthesized histones are enriched in the differentiating daughter cell. We also found that randomized inheritance of preexisting histones versus newly synthesized histones results in both stem cell loss and progenitor germ cell tumor phenotypes, suggesting that programmed histone inheritance is a key epigenetic player for cells to either remember or reset cell fates. Here, we will discuss these findings in the context of current knowledge on DNA replication, polarized mitotic machinery, and ACD for both animal development and tissue homeostasis. We will also speculate on some potential mechanisms underlying asymmetric histone inheritance, which may be used in other biological events to achieve the asymmetric cell fates.
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19
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Seah MKY, Messerschmidt DM. From Germline to Soma: Epigenetic Dynamics in the Mouse Preimplantation Embryo. Curr Top Dev Biol 2017; 128:203-235. [PMID: 29477164 DOI: 10.1016/bs.ctdb.2017.10.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
When reflecting about cell fate commitment we think of differentiation. Be it during embryonic development or in an adult stem cell niche, where cells of a higher potency specialize and cell fate decisions are taken. Under normal circumstances this process is definitive and irreversible. Cell fate commitment is achieved by the establishment of cell-type-specific transcriptional programmes, which in turn are guided, reinforced, and ultimately locked-in by epigenetic mechanisms. Yet, this plunging drift in cellular potency linked to epigenetically restricted access to genomic information is problematic for reproduction. Particularly in mammals where germ cells are not set aside early on like in other species. Instead they are rederived from the embryonic ectoderm, a differentiating embryonic tissue with somatic epigenetic features. The epigenomes of germ cell precursors are efficiently reprogrammed against the differentiation trend, only to specialize once more into highly differentiated, sex-specific gametes: oocyte and sperm. Their differentiation state is reflected in their specialized epigenomes, and erasure of these features is required to enable the acquisition of the totipotent cell fate to kick start embryonic development of the next generation. Recent technological advances have enabled unprecedented insights into the epigenetic dynamics, first of DNA methylation and then of histone modifications, greatly expanding the historically technically limited understanding of this processes. In this chapter we will focus on the details of embryonic epigenetic reprogramming, a cell fate determination process against the tide to a higher potency.
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Affiliation(s)
- Michelle K Y Seah
- Developmental Epigenetics and Disease Group, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Daniel M Messerschmidt
- Developmental Epigenetics and Disease Group, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
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20
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Abstract
Semiconservative DNA replication has provided an elegant solution to the fundamental problem of how life is able to proliferate in a way that allows cells, organisms, and populations to survive and replicate many times over. Somewhat lost, however, in our admiration for this mechanism is an appreciation for the asymmetries that occur in the process of DNA replication. As we discuss in this review, these asymmetries arise as a consequence of the structure of the DNA molecule and the enzymatic mechanism of DNA synthesis. Increasing evidence suggests that asymmetries in DNA replication are able to play a central role in the processes of adaptation and evolution by shaping the mutagenic landscape of cells. Additionally, in eukaryotes, recent work has demonstrated that the inherent asymmetries in DNA replication may play an important role in the process of chromatin replication. As chromatin plays an essential role in defining cell identity, asymmetries generated during the process of DNA replication may play critical roles in cell fate decisions related to patterning and development.
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Affiliation(s)
- Jonathan Snedeker
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland 21218; , ,
| | - Matthew Wooten
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland 21218; , ,
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland 21218; , ,
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21
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Abstract
The physiological identity of every cell is maintained by highly specific transcriptional networks that establish a coherent molecular program that is in tune with nutritional conditions. The regulation of cell-specific transcriptional networks is accomplished by an epigenetic program via chromatin-modifying enzymes, whose activity is directly dependent on metabolites such as acetyl-coenzyme A, S-adenosylmethionine, and NAD+, among others. Therefore, these nuclear activities are directly influenced by the nutritional status of the cell. In addition to nutritional availability, this highly collaborative program between epigenetic dynamics and metabolism is further interconnected with other environmental cues provided by the day-night cycles imposed by circadian rhythms. Herein, we review molecular pathways and their metabolites associated with epigenetic adaptations modulated by histone- and DNA-modifying enzymes and their responsiveness to the environment in the context of health and disease.
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22
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Coleman RT, Struhl G. Causal role for inheritance of H3K27me3 in maintaining the OFF state of a Drosophila HOX gene. Science 2017; 356:eaai8236. [PMID: 28302795 PMCID: PMC5595140 DOI: 10.1126/science.aai8236] [Citation(s) in RCA: 140] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 02/03/2017] [Indexed: 12/20/2022]
Abstract
Many eukaryotic cells can respond to transient environmental or developmental stimuli with heritable changes in gene expression that are associated with nucleosome modifications. However, it remains uncertain whether modified nucleosomes play a causal role in transmitting such epigenetic memories, as opposed to controlling or merely reflecting transcriptional states inherited by other means. Here, we provide in vivo evidence that H3K27 trimethylated nucleosomes, once established at a repressed Drosophila HOX gene, remain heritably associated with that gene and can carry the memory of the silenced state through multiple rounds of replication, even when the capacity to copy the H3K27me3 mark to newly incorporated nucleosomes is diminished or abolished. Hence, in this context, the inheritance of H3K27 trimethylation conveys epigenetic memory.
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Affiliation(s)
- Rory T Coleman
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York, NY 10032, USA
| | - Gary Struhl
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York, NY 10032, USA.
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23
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Xie J, Wooten M, Tran V, Chen X. Breaking Symmetry - Asymmetric Histone Inheritance in Stem Cells. Trends Cell Biol 2017; 27:527-540. [PMID: 28268050 DOI: 10.1016/j.tcb.2017.02.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 01/27/2017] [Accepted: 02/01/2017] [Indexed: 01/17/2023]
Abstract
Asymmetric cell division (ACD) gives rise to two daughter cells with distinct fates. ACD is widely used during development and by many types of adult stem cells during tissue homeostasis and regeneration. ACD can be regulated by extrinsic cues, such as signaling molecules, as well as by intrinsic factors, such as organelles and cortex proteins. The recent discovery of asymmetric histone inheritance during stem cell ACD has revealed another intrinsic mechanism by which ACD produces two distinct daughters. In this review we discuss these findings in the context of cell-cycle regulation, as well as other studies of ACD, to begin understanding the underlying mechanisms and biological relevance of this phenomenon.
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Affiliation(s)
- Jing Xie
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Matthew Wooten
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Vuong Tran
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA; Current address: Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North Seattle, Seattle, WA 98109, USA
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
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24
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A model of dynamic stability of H3K9me3 heterochromatin to explain the resistance to reprogramming of differentiated cells. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1860:184-195. [DOI: 10.1016/j.bbagrm.2016.11.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 11/16/2016] [Accepted: 11/17/2016] [Indexed: 12/16/2022]
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25
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Cadmium affects mitotically inherited histone modification pathways in mouse embryonic stem cells. Toxicol In Vitro 2015; 30:583-92. [PMID: 26562325 DOI: 10.1016/j.tiv.2015.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/19/2015] [Accepted: 11/02/2015] [Indexed: 11/21/2022]
Abstract
The fetal basis of adult disease (FeBAD) theorizes that embryonic challenges initiate pathologies in adult life through epigenetic modification of gene expression. In addition, inheritance of H3K27 methylation marks, especially in vitro, is still controversial. Metals, such as Cd, are known to affect differentiation, DNA repair and epigenetic status in mES cells. We tested the premise that Cd exerts differential toxicity in mouse embryonic stem (mES) cells by targeting total histone protein (THP) production early in stem cell development, while affecting H3K27-mono-methylation (H3K27me(1)) in latter stages of differentiation. The inability of mES cells to recover from Cd insult at concentrations greater than IC50 indicates that maximum cytotoxicity occurs during initial hours of exposure. Moreover, as a measure of chromatin stability, low dose acute Cd exposure lowers THP production. The heritable effects of Cd exposure on cell proliferation, chromatin stability and transcription observed through several cell population doublings were detected only during alternate passages on days 3, 7, and 11, presumably due to slower maturation of histone methylation marks. These findings demonstrate a selective disruption of chromatin structure following acute Cd exposure, an effect not seen in developmentally mature cells. Hence, we present that acute Cd toxicity is cumulative and disrupts DNA repair, while concurrently affecting cell cycle progression, chromatin stability and transcriptional state in mES cells.
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26
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Editorial overview: Cancer: Changing the landscape - new pharmacology steering the course towards improved treatment options in cancer. Curr Opin Pharmacol 2015; 23:iv-vi. [PMID: 26091611 DOI: 10.1016/j.coph.2015.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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27
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28
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Audergon PNCB, Catania S, Kagansky A, Tong P, Shukla M, Pidoux AL, Allshire RC. Epigenetics. Restricted epigenetic inheritance of H3K9 methylation. Science 2015; 348:132-5. [PMID: 25838386 PMCID: PMC4397586 DOI: 10.1126/science.1260638] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Posttranslational histone modifications are believed to allow the epigenetic transmission of distinct chromatin states, independently of associated DNA sequences. Histone H3 lysine 9 (H3K9) methylation is essential for heterochromatin formation; however, a demonstration of its epigenetic heritability is lacking. Fission yeast has a single H3K9 methyltransferase, Clr4, that directs all H3K9 methylation and heterochromatin. Using releasable tethered Clr4 reveals that an active process rapidly erases H3K9 methylation from tethering sites in wild-type cells. However, inactivation of the putative histone demethylase Epe1 allows H3K9 methylation and silent chromatin maintenance at the tethering site through many mitotic divisions, and transgenerationally through meiosis, after release of tethered Clr4. Thus, H3K9 methylation is a heritable epigenetic mark whose transmission is usually countered by its active removal, which prevents the unauthorized inheritance of heterochromatin.
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Affiliation(s)
- Pauline N C B Audergon
- Wellcome Trust Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK
| | - Sandra Catania
- Wellcome Trust Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK
| | - Alexander Kagansky
- Wellcome Trust Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK
| | - Pin Tong
- Wellcome Trust Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK
| | - Manu Shukla
- Wellcome Trust Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK
| | - Alison L Pidoux
- Wellcome Trust Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK
| | - Robin C Allshire
- Wellcome Trust Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK.
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29
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Liu N, Zhang Z, Wu H, Jiang Y, Meng L, Xiong J, Zhao Z, Zhou X, Li J, Li H, Zheng Y, Chen S, Cai T, Gao S, Zhu B. Recognition of H3K9 methylation by GLP is required for efficient establishment of H3K9 methylation, rapid target gene repression, and mouse viability. Genes Dev 2015; 29:379-93. [PMID: 25637356 PMCID: PMC4335294 DOI: 10.1101/gad.254425.114] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
GLP and G9a are major H3K9 dimethylases essential for mouse early embryonic development. Here, Liu et al. report that the histone methyltransferase activities of GLP and G9a are stimulated by neighboring nucleosomes that are premethylated at H3K9. In mouse embryonic stem cells harboring a mutant GLP that lacks H3K9me1-binding activity, critical pluripotent genes displayed inefficient establishment of H3K9me2 and delayed gene silencing during differentiation. Mice carrying the H3K9me1-binding mutant form of GLP displayed embryonic growth retardation and defects in calvaria bone formation. GLP and G9a are major H3K9 dimethylases and are essential for mouse early embryonic development. GLP and G9a both harbor ankyrin repeat domains that are capable of binding H3K9 methylation. However, the functional significance of their recognition of H3K9 methylation is unknown. Here, we report that the histone methyltransferase activities of GLP and G9a are stimulated by neighboring nucleosomes that are premethylated at H3K9. These stimulation events function in cis and are dependent on the H3K9 methylation binding activities of ankyrin repeat domains of GLP and G9a. Disruption of the H3K9 methylation-binding activity of GLP in mice causes growth retardation of embryos, ossification defects of calvaria, and postnatal lethality due to starvation of the pups. In mouse embryonic stem cells (ESCs) harboring a mutant GLP that lacks H3K9me1-binding activity, critical pluripotent genes, including Oct4 and Nanog, display inefficient establishment of H3K9me2 and delayed gene silencing during differentiation. Collectively, our study reveals a new activation mechanism for GLP and G9a that plays an important role in ESC differentiation and mouse viability.
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Affiliation(s)
- Nan Liu
- College of Life Sciences, Beijing Normal University, Beijing 100875, China; National Institute of Biological Sciences, Beijing 102206, China; National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhuqiang Zhang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Hui Wu
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, Jilin Province 130012, China;
| | - Yonghua Jiang
- National Institute of Biological Sciences, Beijing 102206, China
| | - Lingjun Meng
- National Institute of Biological Sciences, Beijing 102206, China
| | - Jun Xiong
- National Institute of Biological Sciences, Beijing 102206, China
| | - Zuodong Zhao
- National Institute of Biological Sciences, Beijing 102206, China
| | - Xiaohua Zhou
- National Institute of Biological Sciences, Beijing 102206, China
| | - Jia Li
- National Institute of Biological Sciences, Beijing 102206, China
| | - Hong Li
- National Institute of Biological Sciences, Beijing 102206, China
| | - Yong Zheng
- National Institute of Biological Sciences, Beijing 102206, China
| | - She Chen
- National Institute of Biological Sciences, Beijing 102206, China
| | - Tao Cai
- National Institute of Biological Sciences, Beijing 102206, China
| | - Shaorong Gao
- School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Bing Zhu
- National Institute of Biological Sciences, Beijing 102206, China; National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China;
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30
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Chandra V, Hong KM. Effects of deranged metabolism on epigenetic changes in cancer. Arch Pharm Res 2015; 38:321-37. [PMID: 25628247 DOI: 10.1007/s12272-015-0561-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 01/09/2015] [Indexed: 12/17/2022]
Abstract
The concept of epigenetics is now providing the mechanisms by which cells transfer their new environmental-change-induced phenotypes to their daughter cells. However, how extracellular or cytoplasmic environmental cues are connected to the nuclear epigenome remains incompletely understood. Recently emerging evidence suggests that epigenetic changes are correlated with metabolic changes via chromatin remodeling. As many human complex diseases including cancer harbor both epigenetic changes and metabolic dysregulation, understanding the molecular processes linking them has huge implications for disease pathogenesis and therapeutic intervention. In this review, the impacts of metabolic changes on cancer epigenetics are discussed, along with the current knowledge on cancer metabolism and epigenetics.
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Affiliation(s)
- Vishal Chandra
- Cancer Cell and Molecular Biology Branch, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, 410-769, Korea
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31
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Product binding enforces the genomic specificity of a yeast polycomb repressive complex. Cell 2014; 160:204-18. [PMID: 25533783 DOI: 10.1016/j.cell.2014.11.039] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 09/30/2014] [Accepted: 11/12/2014] [Indexed: 11/22/2022]
Abstract
We characterize the Polycomb system that assembles repressive subtelomeric domains of H3K27 methylation (H3K27me) in the yeast Cryptococcus neoformans. Purification of this PRC2-like protein complex reveals orthologs of animal PRC2 components as well as a chromodomain-containing subunit, Ccc1, which recognizes H3K27me. Whereas removal of either the EZH or EED ortholog eliminates H3K27me, disruption of mark recognition by Ccc1 causes H3K27me to redistribute. Strikingly, the resulting pattern of H3K27me coincides with domains of heterochromatin marked by H3K9me. Indeed, additional removal of the C. neoformans H3K9 methyltransferase Clr4 results in loss of both H3K9me and the redistributed H3K27me marks. These findings indicate that the anchoring of a chromatin-modifying complex to its product suppresses its attraction to a different chromatin type, explaining how enzymes that act on histones, which often harbor product recognition modules, may deposit distinct chromatin domains despite sharing a highly abundant and largely identical substrate-the nucleosome.
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32
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Choi Y, Mango SE. Hunting for Darwin's gemmules and Lamarck's fluid: Transgenerational signaling and histone methylation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1839:1440-53. [DOI: 10.1016/j.bbagrm.2014.05.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Revised: 05/07/2014] [Accepted: 05/13/2014] [Indexed: 01/22/2023]
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33
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Libby EN, Becker PS, Burwick N, Green DJ, Holmberg L, Bensinger WI. Panobinostat: a review of trial results and future prospects in multiple myeloma. Expert Rev Hematol 2014; 8:9-18. [PMID: 25410127 DOI: 10.1586/17474086.2015.983065] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Multiple myeloma is an incurable often devastating disease that is responsible for 1-2% of all cancers. Multiple myeloma is the second most common hematologic malignancy. Over the past two decades, advances in therapy have doubled life expectancy. Unfortunately, all patients ultimately relapse. Novel agents (immunomodulatory drugs and proteasome inhibitors) have changed the outlook for patients, but further breakthroughs are needed. Epigenetic treatments offer potential for advancing therapy by modifying oncogene responses. The acetylation status of various proteins can affect the availability of chromatin for transcription. This response may be modulated epigenetically to advantage using histone deacetylase inhibitors like panobinostat.
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Affiliation(s)
- Edward N Libby
- University of Washington School of Medicine - Medical Oncology, 825 Eastlake Ave E, Seattle, WA 98109, USA
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34
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Jiang N, Wang L, Chen J, Wang L, Leach L, Luo Z. Conserved and divergent patterns of DNA methylation in higher vertebrates. Genome Biol Evol 2014; 6:2998-3014. [PMID: 25355807 PMCID: PMC4255770 DOI: 10.1093/gbe/evu238] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/20/2014] [Indexed: 02/07/2023] Open
Abstract
DNA methylation in the genome plays a fundamental role in the regulation of gene expression and is widespread in the genome of eukaryotic species. For example, in higher vertebrates, there is a "global" methylation pattern involving complete methylation of CpG sites genome-wide, except in promoter regions that are typically enriched for CpG dinucleotides, or so called "CpG islands." Here, we comprehensively examined and compared the distribution of CpG sites within ten model eukaryotic species and linked the observed patterns to the role of DNA methylation in controlling gene transcription. The analysis revealed two distinct but conserved methylation patterns for gene promoters in human and mouse genomes, involving genes with distinct distributions of promoter CpGs and gene expression patterns. Comparative analysis with four other higher vertebrates revealed that the primary regulatory role of the DNA methylation system is highly conserved in higher vertebrates.
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Affiliation(s)
- Ning Jiang
- Department of Biostatistics & Computational Biology, SKLG, School of Life Sciences, Fudan University, Shanghai, China School of Biosciences, The University of Birmingham, Birmingham B15 2TT United Kingdom
| | - Lin Wang
- Department of Biostatistics & Computational Biology, SKLG, School of Life Sciences, Fudan University, Shanghai, China
| | - Jing Chen
- School of Biosciences, The University of Birmingham, Birmingham B15 2TT United Kingdom
| | - Luwen Wang
- Department of Biostatistics & Computational Biology, SKLG, School of Life Sciences, Fudan University, Shanghai, China
| | - Lindsey Leach
- School of Biosciences, The University of Birmingham, Birmingham B15 2TT United Kingdom
| | - Zewei Luo
- Department of Biostatistics & Computational Biology, SKLG, School of Life Sciences, Fudan University, Shanghai, China School of Biosciences, The University of Birmingham, Birmingham B15 2TT United Kingdom
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35
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Petruk S, Black KL, Kovermann SK, Brock HW, Mazo A. Stepwise histone modifications are mediated by multiple enzymes that rapidly associate with nascent DNA during replication. Nat Commun 2014; 4:2841. [PMID: 24276476 PMCID: PMC3874871 DOI: 10.1038/ncomms3841] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 10/29/2013] [Indexed: 11/10/2022] Open
Abstract
The mechanism of epigenetic inheritance following DNA replication may involve dissociation of chromosomal proteins from parental DNA and reassembly on daughter strands in a specific order. Here we investigated the behavior of different types of chromosomal proteins using newly developed methods that allow assessment of the assembly of proteins during DNA replication. Unexpectedly, most chromatin-modifying proteins tested, including methylases, demethylases, acetyltransferases and a deacetylase, are found in close proximity to PCNA or associate with short nascent DNA. Histone modifications occur in a temporal order following DNA replication, mediated by complex activities of different enzymes. In contrast, components of several major nucleosome remodeling complexes are dissociated from parental DNA, and are later recruited to nascent DNA following replication. Epigenetic inheritance of gene expression patterns may require many aspects of chromatin structure to remain in close proximity to the replication complex followed by re-assembly on nascent DNA shortly after replication.
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Affiliation(s)
- Svetlana Petruk
- Department of Biochemistry and Molecular Biology and Kimmel Cancer Center, Thomas Jefferson University, 1020 Locust Street, Philadelphia, Pennsylvania 19107, USA
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36
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Abstract
Epigenetic control of gene expression programs is essential for normal organismal development and cellular function. Abrogation of epigenetic regulation is seen in many human diseases, including cancer and neuropsychiatric disorders, where it can affect disease etiology and progression. Abnormal epigenetic profiles can serve as biomarkers of disease states and predictors of disease outcomes. Therefore, epigenetics is a key area of clinical investigation in diagnosis, prognosis, and treatment. In this review, we give an overarching view of epigenetic mechanisms of human disease. Genetic mutations in genes that encode chromatin regulators can cause monogenic disease or are incriminated in polygenic, multifactorial diseases. Environmental stresses can also impact directly on chromatin regulation, and these changes can increase the risk of, or directly cause, disease. Finally, emerging evidence suggests that exposure to environmental stresses in older generations may predispose subsequent generations to disease in a manner that involves the transgenerational inheritance of epigenetic information.
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Affiliation(s)
- Emily Brookes
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115
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37
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Bloomfield JA, Rose TJ, King GJ. Sustainable harvest: managing plasticity for resilient crops. PLANT BIOTECHNOLOGY JOURNAL 2014; 12:517-33. [PMID: 24891039 PMCID: PMC4207195 DOI: 10.1111/pbi.12198] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 04/14/2014] [Indexed: 05/18/2023]
Abstract
Maintaining crop production to feed a growing world population is a major challenge for this period of rapid global climate change. No consistent conceptual or experimental framework for crop plants integrates information at the levels of genome regulation, metabolism, physiology and response to growing environment. An important role for plasticity in plants is assisting in homeostasis in response to variable environmental conditions. Here, we outline how plant plasticity is facilitated by epigenetic processes that modulate chromatin through dynamic changes in DNA methylation, histone variants, small RNAs and transposable elements. We present examples of plant plasticity in the context of epigenetic regulation of developmental phases and transitions and map these onto the key stages of crop establishment, growth, floral initiation, pollination, seed set and maturation of harvestable product. In particular, we consider how feedback loops of environmental signals and plant nutrition affect plant ontogeny. Recent advances in understanding epigenetic processes enable us to take a fresh look at the crosstalk between regulatory systems that confer plasticity in the context of crop development. We propose that these insights into genotype × environment (G × E) interaction should underpin development of new crop management strategies, both in terms of information-led agronomy and in recognizing the role of epigenetic variation in crop breeding.
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Affiliation(s)
- Justin A Bloomfield
- Southern Cross Plant Science, Southern Cross UniversityLismore, NSW, Australia
| | - Terry J Rose
- Southern Cross Plant Science, Southern Cross UniversityLismore, NSW, Australia
| | - Graham J King
- Southern Cross Plant Science, Southern Cross UniversityLismore, NSW, Australia
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38
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Abstract
Epigenetic regulation of cellular identity and function is at least partly achieved through changes in covalent modifications on DNA and histones. Much progress has been made in recent years to understand how these covalent modifications affect cell identity and function. Despite the advances, whether and how epigenetic factors contribute to memory formation is still poorly understood. In this review, we discuss recent progress in elucidating epigenetic mechanisms of learning and memory, primarily at the DNA level, and look ahead to discuss their potential implications in reward memory and development of drug addiction.
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Affiliation(s)
- Luis M Tuesta
- Howard Hughes Medical Institute, Boston, MA, USA Program in Cellular and Molecular Medicine Boston Children's Hospital, Boston, MA, USA Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Yi Zhang
- Howard Hughes Medical Institute, Boston, MA, USA Program in Cellular and Molecular Medicine Boston Children's Hospital, Boston, MA, USA Department of Genetics, Harvard Medical School, Boston, MA, USA Harvard Stem Cell Institute Harvard Medical School, Boston, MA, USA
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39
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D'Urso A, Brickner JH. Mechanisms of epigenetic memory. Trends Genet 2014; 30:230-6. [PMID: 24780085 DOI: 10.1016/j.tig.2014.04.004] [Citation(s) in RCA: 153] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 03/31/2014] [Accepted: 04/01/2014] [Indexed: 11/20/2022]
Abstract
Although genetics has an essential role in defining the development, morphology, and physiology of an organism, epigenetic mechanisms have an essential role in modulating these properties by regulating gene expression. During development, epigenetic mechanisms establish stable gene expression patterns to ensure proper differentiation. Such mechanisms also allow organisms to adapt to environmental changes and previous experiences can impact the future responsiveness of an organism to a stimulus over long timescales and even over generations. Here, we discuss the concept of epigenetic memory, defined as the stable propagation of a change in gene expression or potential induced by developmental or environmental stimuli. We highlight three distinct paradigms of epigenetic memory that operate on different timescales.
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Affiliation(s)
- Agustina D'Urso
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA
| | - Jason H Brickner
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA.
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40
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DNA replication components as regulators of epigenetic inheritance--lesson from fission yeast centromere. Protein Cell 2014; 5:411-9. [PMID: 24691906 PMCID: PMC4026425 DOI: 10.1007/s13238-014-0049-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 02/24/2014] [Indexed: 01/30/2023] Open
Abstract
Genetic information stored in DNA is accurately copied and transferred to subsequent generations through DNA replication. This process is accomplished through the concerted actions of highly conserved DNA replication components. Epigenetic information stored in the form of histone modifications and DNA methylation, constitutes a second layer of regulatory information important for many cellular processes, such as gene expression regulation, chromatin organization, and genome stability. During DNA replication, epigenetic information must also be faithfully transmitted to subsequent generations. How this monumental task is achieved remains poorly understood. In this review, we will discuss recent advances on the role of DNA replication components in the inheritance of epigenetic marks, with a particular focus on epigenetic regulation in fission yeast. Based on these findings, we propose that specific DNA replication components function as key regulators in the replication of epigenetic information across the genome.
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41
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Rivera C, Gurard-Levin ZA, Almouzni G, Loyola A. Histone lysine methylation and chromatin replication. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1839:1433-9. [PMID: 24686120 DOI: 10.1016/j.bbagrm.2014.03.009] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 03/12/2014] [Accepted: 03/20/2014] [Indexed: 01/20/2023]
Abstract
In eukaryotic organisms, the replication of the DNA sequence and its organization into chromatin are critical to maintain genome integrity. Chromatin components, such as histone variants and histone post-translational modifications, along with the higher-order chromatin structure, impact several DNA metabolic processes, including replication, transcription, and repair. In this review we focus on lysine methylation and the relationships between this histone mark and chromatin replication. We first describe studies implicating lysine methylation in regulating early steps in the replication process. We then discuss chromatin reassembly following replication fork passage, where the incorporation of a combination of newly synthesized histones and parental histones can impact the inheritance of lysine methylation marks on the daughter strands. Finally, we elaborate on how the inheritance of lysine methylation can impact maintenance of the chromatin landscape, using heterochromatin as a model chromatin domain, and we discuss the potential mechanisms involved in this process.
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Affiliation(s)
| | - Zachary A Gurard-Levin
- Institut Curie, Centre de Recherche, Paris F-75248, France; CNRS, UMR 3664, Paris F-75248, France; Equipe Labellisée Ligue contre le Cancer, UMR 3664, Paris F-75248, France; UPMC, UMR 3664, Paris F-75248, France; Paris Sciences & Lettres, PSL, France
| | - Geneviève Almouzni
- Institut Curie, Centre de Recherche, Paris F-75248, France; CNRS, UMR 3664, Paris F-75248, France; Equipe Labellisée Ligue contre le Cancer, UMR 3664, Paris F-75248, France; UPMC, UMR 3664, Paris F-75248, France; Paris Sciences & Lettres, PSL, France.
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42
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Youngson NA, Lin PC, Lin SS. The convergence of autophagy, small RNA and the stress response – implications for transgenerational epigenetic inheritance in plants. Biomol Concepts 2014; 5:1-8. [DOI: 10.1515/bmc-2013-0032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Accepted: 11/22/2013] [Indexed: 12/25/2022] Open
Abstract
AbstractRecent discoveries in eukaryotes have shown that autophagy-mediated degradation of DICER and ARGONAUTE (AGO), the proteins involved in post-transcriptional gene silencing (PTGS), can occur in response to viral infection and starvation. In plants, a virally encoded protein P0 specifically interacts with AGO1 and enhances degradation through autophagy, resulting in suppression of gene silencing. In HeLa cells, DICER and AGO2 protein levels decreased after nutrient starvation or after treatment to increase autophagy. Environmental exposures to viral infection and starvation have also recently been shown to sometimes not only induce a stress response in the exposed plant but also in their unexposed progeny. These, and other cases of inherited stress response in plants are thought to be facilitated through transgenerational epigenetic inheritance, and the mechanism involves the PTGS and transcriptional gene silencing (TGS) pathways. These recent discoveries suggest that the environmentally-induced autophagic degradation of the PTGS and TGS components may have significant effects on inherited stress responses.
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Affiliation(s)
- Neil A. Youngson
- 1Department of Pharmacology, School of Medical Sciences, UNSW Medicine, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Pin-Chun Lin
- 2Institute of Biotechnology, National Taiwan University, 81, Chang-Xing St., Taipei, Taiwan 106
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43
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Histone variants and epigenetic inheritance. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1819:222-229. [PMID: 24459724 DOI: 10.1016/j.bbagrm.2011.06.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nucleosome particles, which are composed of core histones and DNA, are the basic unit of eukaryotic chromatin. Histone modifications and histone composition determine the structure and function of the chromatin; this genome packaging, often referred to as "epigenetic information", provides additional information beyond the underlying genomic sequence. The epigenetic information must be transmitted from mother cells to daughter cells during mitotic division to maintain the cell lineage identity and proper gene expression. However, the mechanisms responsible for mitotic epigenetic inheritance remain largely unknown. In this review, we focus on recent studies regarding histone variants and discuss the assembly pathways that may contribute to epigenetic inheritance. This article is part of a Special Issue entitled: Histone chaperones and Chromatin assembly.
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44
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Asymmetric distribution of histones during Drosophila male germline stem cell asymmetric divisions. Chromosome Res 2014; 21:255-69. [PMID: 23681658 DOI: 10.1007/s10577-013-9356-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
It has long been known that epigenetic changes are inheritable. However, except for DNA methylation, little is known about the molecular mechanisms of epigenetic inheritance. Many types of stem cells undergo asymmetric cell divisions to generate self-renewed stem cells and daughter cells committed for differentiation. Still, whether and how stem cells retain their epigenetic memory remain questions to be elucidated. During the asymmetric division of Drosophila male germline stem cell (GSC), our recent studies revealed that the preexisting histone 3 (H3) are selectively segregated to the GSC, whereas newly synthesized H3 deposited during DNA replication are enriched in the differentiating daughter cell. We propose a two-step model to explain this asymmetric histone distribution. First, prior to mitosis, preexisting histones and newly synthesized histones are differentially distributed at two sets of sister chromatids. Next, during mitosis, the set of sister chromatids that mainly consist of preexisting histones are segregated to GSCs, while the other set of sister chromatids enriched with newly synthesized histones are partitioned to the daughter cell committed for differentiation. In this review, we apply current knowledge about epigenetic inheritance and asymmetric cell division to inform our discussion of potential molecular mechanisms and the cellular basis underlying this asymmetric histone distribution pattern. We will also discuss whether this phenomenon contributes to the maintenance of stem cell identity and resetting chromatin structure in the other daughter cell for differentiation.
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45
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Cheedipudi S, Genolet O, Dobreva G. Epigenetic inheritance of cell fates during embryonic development. Front Genet 2014; 5:19. [PMID: 24550937 PMCID: PMC3912789 DOI: 10.3389/fgene.2014.00019] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Accepted: 01/21/2014] [Indexed: 01/25/2023] Open
Abstract
During embryonic development a large number of widely differing and specialized cell types with identical genomes are generated from a single totipotent zygote. Tissue specific transcription factors cooperate with epigenetic modifiers to establish cellular identity in differentiated cells and epigenetic regulatory mechanisms contribute to the maintenance of distinct chromatin states and cell-type specific gene expression patterns, a phenomenon referred to as epigenetic memory. This is accomplished via the stable maintenance of various epigenetic marks through successive rounds of cell division. Preservation of DNA methylation patterns is a well-established mechanism of epigenetic memory, but more recently it has become clear that many other epigenetic modifications can also be maintained following DNA replication and cell division. In this review, we present an overview of the current knowledge regarding the role of histone lysine methylation in the establishment and maintenance of stable epigenetic states.
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Affiliation(s)
- Sirisha Cheedipudi
- Origin of Cardiac Cell Lineages Group, Max Planck Institute for Heart and Lung Research Bad Nauheim, Germany ; Medical Faculty, J. W. Goethe University Frankfurt Frankfurt, Germany
| | - Oriana Genolet
- Origin of Cardiac Cell Lineages Group, Max Planck Institute for Heart and Lung Research Bad Nauheim, Germany ; Medical Faculty, J. W. Goethe University Frankfurt Frankfurt, Germany
| | - Gergana Dobreva
- Origin of Cardiac Cell Lineages Group, Max Planck Institute for Heart and Lung Research Bad Nauheim, Germany ; Medical Faculty, J. W. Goethe University Frankfurt Frankfurt, Germany
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46
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Nicol-Benoit F, le Goff P, Michel D. Drawing a Waddington landscape to capture dynamic epigenetics. Biol Cell 2013; 105:576-84. [PMID: 24111561 DOI: 10.1111/boc.201300029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 09/10/2013] [Indexed: 01/08/2023]
Abstract
Epigenetics is most often reduced to chromatin marking in the current literature, whereas this notion was initially defined in a more general context. This restricted view ignores that epigenetic memories are in fact more robustly ensured in living systems by steady-state mechanisms with permanent molecule renewal. This misconception is likely to result from misleading intuitions and insufficient dialogues between traditional and quantitative biologists. To demystify dynamic epigenetics, its most famous image, a Waddington landscape and its attractors, are explicitly drawn. The simple example provided, is sufficient to highlight the main requirements and characteristics of dynamic gene networks, underlying cellular differentiation, de-differentiation and trans-differentiation.
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Affiliation(s)
- Floriane Nicol-Benoit
- Université de Rennes 1 IRSET U1085 Transcription, Environment and Cancer, Campus de Beaulieu, Rennes Cedex, 35042, France
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47
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How is epigenetic information maintained through DNA replication? Epigenetics Chromatin 2013; 6:32. [PMID: 24225278 PMCID: PMC3852060 DOI: 10.1186/1756-8935-6-32] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 09/12/2013] [Indexed: 12/23/2022] Open
Abstract
DNA replication is a highly conserved process that accurately copies the genetic information from one generation to the next. The processes of chromatin disassembly and reassembly during DNA replication also have to be precisely regulated to ensure that the genetic material is compactly packaged to fit into the nucleus while also maintaining the epigenetic information that is carried by the histone proteins bound to the DNA, through cell divisions. Half of the histones that are deposited during replication are from the parental chromatin and carry the parental epigenetic information, while the other half of the histones are newly-synthesized. It has been of growing interest to understand how the parental pattern of epigenetic marks is re-established on the newly-synthesized histones, in a DNA sequence-specific manner, in order to maintain the epigenetic information through cell divisions. In this review we will discuss how histone chaperone proteins precisely coordinate the chromatin assembly process during DNA replication. We also discuss the recent evidence that histone-modifying enzymes, rather than the parental histones, are themselves epigenetic factors that remain associated with the DNA through replication to re-establish the epigenetic information on the newly-assembled chromatin.
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48
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Qian MX, Pang Y, Liu CH, Haratake K, Du BY, Ji DY, Wang GF, Zhu QQ, Song W, Yu Y, Zhang XX, Huang HT, Miao S, Chen LB, Zhang ZH, Liang YN, Liu S, Cha H, Yang D, Zhai Y, Komatsu T, Tsuruta F, Li H, Cao C, Li W, Li GH, Cheng Y, Chiba T, Wang L, Goldberg AL, Shen Y, Qiu XB. Acetylation-mediated proteasomal degradation of core histones during DNA repair and spermatogenesis. Cell 2013; 153:1012-24. [PMID: 23706739 DOI: 10.1016/j.cell.2013.04.032] [Citation(s) in RCA: 227] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 03/11/2013] [Accepted: 04/08/2013] [Indexed: 01/12/2023]
Abstract
Histone acetylation plays critical roles in chromatin remodeling, DNA repair, and epigenetic regulation of gene expression, but the underlying mechanisms are unclear. Proteasomes usually catalyze ATP- and polyubiquitin-dependent proteolysis. Here, we show that the proteasomes containing the activator PA200 catalyze the polyubiquitin-independent degradation of histones. Most proteasomes in mammalian testes ("spermatoproteasomes") contain a spermatid/sperm-specific α subunit α4 s/PSMA8 and/or the catalytic β subunits of immunoproteasomes in addition to PA200. Deletion of PA200 in mice abolishes acetylation-dependent degradation of somatic core histones during DNA double-strand breaks and delays core histone disappearance in elongated spermatids. Purified PA200 greatly promotes ATP-independent proteasomal degradation of the acetylated core histones, but not polyubiquitinated proteins. Furthermore, acetylation on histones is required for their binding to the bromodomain-like regions in PA200 and its yeast ortholog, Blm10. Thus, PA200/Blm10 specifically targets the core histones for acetylation-mediated degradation by proteasomes, providing mechanisms by which acetylation regulates histone degradation, DNA repair, and spermatogenesis.
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Affiliation(s)
- Min-Xian Qian
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, and College of Life Sciences, Beijing Normal University, 19 Xinjiekouwai Avenue, Beijing 100875, China
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49
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Monteiro JB, Colón-Díaz M, García M, Gutierrez S, Colón M, Seto E, Laboy J, Flores I. Endometriosis is characterized by a distinct pattern of histone 3 and histone 4 lysine modifications. Reprod Sci 2013; 21:305-18. [PMID: 23899551 DOI: 10.1177/1933719113497267] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The histone modification patterns in endometriosis have not been fully characterized. This gap in knowledge results in a poor understanding of the epigenetic mechanisms (and potential therapeutic targets) at play. We aimed to (1) assess global acetylation status of histone 3 (H3) and histone 4 (H4), (2) measure levels of H3 and H4 lysine (K) acetylation and methylation, and (3) to identify histone acetylation patterns in promoter regions of candidate genes in tissues from patients and controls. METHODS Global and K-specific acetylation/methylation levels of histones were measured in 24 lesions, 15 endometrium from patients, and 26 endometrium from controls. Chromatin immunoprecipitation (ChIP)-polymerase chain reaction was used to determine the histone acetylation status of the promoter regions of candidate genes in tissues. RESULTS The lesions were globally hypoacetylated at H3 (but not H4) compared to eutopic endometrium from controls. Lesions had significantly lower levels of H3K9ac and H4K16ac compared to eutopic endometrium from patients and controls. Tissues from patients were hypermethylated at H3K4, H3K9, and H3K27 compared to endometrium from controls. The ChIP analysis showed hypoacetylation of H3/H4 within promoter regions of candidate genes known to be downregulated in endometriosis (e.g., HOXA10, ESR1, CDH1, and p21 (WAF1/Cip1) ) in lesions versus control endometrium. The stereoidogenic factor 1 (SF1) promoter region was enriched for acetylated H3 and H4 in lesions versus control tissues, correlating with its reported high expression in lesions. CONCLUSIONS This study describes the histone code of lesions and endometrium from patients with endometriosis and provides support for a possible role of histone modification in modulation of gene expression in endometriosis.
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Affiliation(s)
- Janice B Monteiro
- 1Department of Biochemistry, Ponce School of Medicine and Health Sciences, Ponce, Puerto Rico
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Kallestad L, Woods E, Christensen K, Gefroh A, Balakrishnan L, Milavetz B. Transcription and replication result in distinct epigenetic marks following repression of early gene expression. Front Genet 2013; 4:140. [PMID: 23914205 PMCID: PMC3728471 DOI: 10.3389/fgene.2013.00140] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 07/04/2013] [Indexed: 12/18/2022] Open
Abstract
Simian virus 40 (SV40) early transcription is repressed when the product of early transcription, T-antigen, binds to its cognate regulatory sequence, Site I, in the promoter of the SV40 minichromosome. Because SV40 minichromosomes undergo replication and transcription potentially repression could occur during active transcription or during DNA replication. Since repression is frequently epigenetically marked by the introduction of specific forms of methylated histone H3, we characterized the methylation of H3 tails during transcription and replication in wild-type SV40 minichromosomes and mutant minichromosomes which did not repress T-antigen expression. While repressed minichromosomes following replication were clearly marked with H3K9me1 and H3K4me1, minichromosomes repressed during early transcription were not similarly marked. Instead repression of early transcription was marked by a significant reduction in the level of H3K9me2. The replication dependent introduction of H3K9me1 and H3K4me1 into wild-type SV40 minichromosomes was also observed when replication was inhibited with aphidicolin. The results indicate that the histone modifications associated with repression can differ significantly depending upon whether the chromatin being repressed is undergoing transcription or replication.
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Affiliation(s)
- Les Kallestad
- Department of Biochemistry and Molecular Biology, University of North Dakota School of Medicine and Health Sciences Grand Forks, ND, USA
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