1
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Wong LH, Tremethick DJ. Multifunctional histone variants in genome function. Nat Rev Genet 2024:10.1038/s41576-024-00759-1. [PMID: 39138293 DOI: 10.1038/s41576-024-00759-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2024] [Indexed: 08/15/2024]
Abstract
Histones are integral components of eukaryotic chromatin that have a pivotal role in the organization and function of the genome. The dynamic regulation of chromatin involves the incorporation of histone variants, which can dramatically alter its structural and functional properties. Contrary to an earlier view that limited individual histone variants to specific genomic functions, new insights have revealed that histone variants exert multifaceted roles involving all aspects of genome function, from governing patterns of gene expression at precise genomic loci to participating in genome replication, repair and maintenance. This conceptual change has led to a new understanding of the intricate interplay between chromatin and DNA-dependent processes and how this connection translates into normal and abnormal cellular functions.
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Affiliation(s)
- Lee H Wong
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - David J Tremethick
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capial Territory, Australia.
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2
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Arenas-Mena C, Akin S. Widespread priming of transcriptional regulatory elements by incipient accessibility or RNA polymerase II pause in early embryos of the sea urchin Strongylocentrotus purpuratus. Genetics 2023; 225:iyad145. [PMID: 37551428 PMCID: PMC10789315 DOI: 10.1093/genetics/iyad145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 05/17/2023] [Accepted: 07/25/2023] [Indexed: 08/09/2023] Open
Abstract
Transcriptional regulatory elements (TREs) are the primary nodes that control developmental gene regulatory networks. In embryo stages, larvae, and adult differentiated red spherule cells of the sea urchin Strongylocentrotus purpuratus, transcriptionally engaged TREs are detected by Precision Run-On Sequencing (PRO-seq), which maps genome-wide at base pair resolution the location of paused or elongating RNA polymerase II (Pol II). In parallel, TRE accessibility is estimated by the Assay for Transposase-Accessible Chromatin using Sequencing (ATAC-seq). Our analysis identifies surprisingly early and widespread TRE accessibility in 4-cell cleavage embryos that is not necessarily followed by concurrent or subsequent transcription. TRE transcriptional differences identified by PRO-seq provide more contrast among embryonic stages than ATAC-seq accessibility differences, in agreement with the apparent excess of accessible but inactive TREs during embryogenesis. Global TRE accessibility reaches a maximum around the 20-hour late blastula stage, which coincides with the consolidation of major embryo regionalizations and peak histone variant H2A.Z expression. A transcriptional potency model based on labile nucleosome TRE occupancy driven by DNA sequences and the prevalence of histone variants is proposed in order to explain the basal accessibility of transcriptionally inactive TREs during embryogenesis. However, our results would not reconcile well with labile nucleosome models based on simple A/T sequence enrichment. In addition, a large number of distal TREs become transcriptionally disengaged during developmental progression, in support of an early Pol II paused model for developmental gene regulation that eventually resolves in transcriptional activation or silencing. Thus, developmental potency in early embryos may be facilitated by incipient accessibility and transcriptional pause at TREs.
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Affiliation(s)
- Cesar Arenas-Mena
- Department of Biology, College of Staten Island, City University of New York (CUNY), 2800 Victory Boulevard, Staten Island, NY, 10314, USA
- PhD Programs in Biology and Biochemistry at the City University of New York (CUNY), Graduate Center, 365 Fifth Avenue, New York, NY, 10016, USA
| | - Serhat Akin
- Department of Biology, College of Staten Island, City University of New York (CUNY), 2800 Victory Boulevard, Staten Island, NY, 10314, USA
- PhD Program in Biology at the City University of New York (CUNY), Graduate Center, 365 Fifth Avenue, New York, NY, 10016, USA
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3
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Vu H, Koch Z, Fiziev P, Ernst J. A framework for group-wise summarization and comparison of chromatin state annotations. Bioinformatics 2023; 39:btac722. [PMID: 36342196 PMCID: PMC9805555 DOI: 10.1093/bioinformatics/btac722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 10/12/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
MOTIVATION Genome-wide maps of epigenetic modifications are powerful resources for non-coding genome annotation. Maps of multiple epigenetics marks have been integrated into cell or tissue type-specific chromatin state annotations for many cell or tissue types. With the increasing availability of multiple chromatin state maps for biologically similar samples, there is a need for methods that can effectively summarize the information about chromatin state annotations within groups of samples and identify differences across groups of samples at a high resolution. RESULTS We developed CSREP, which takes as input chromatin state annotations for a group of samples. CSREP then probabilistically estimates the state at each genomic position and derives a representative chromatin state map for the group. CSREP uses an ensemble of multi-class logistic regression classifiers that predict the chromatin state assignment of each sample given the state maps from all other samples. The difference in CSREP's probability assignments for the two groups can be used to identify genomic locations with differential chromatin state assignments. Using groups of chromatin state maps of a diverse set of cell and tissue types, we demonstrate the advantages of using CSREP to summarize chromatin state maps and identify biologically relevant differences between groups at a high resolution. AVAILABILITY AND IMPLEMENTATION The CSREP source code and generated data are available at http://github.com/ernstlab/csrep. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Ha Vu
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Zane Koch
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Petko Fiziev
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Illumina Artificial Intelligence Laboratory, Illumina Inc., Foster City, CA 94404, USA
| | - Jason Ernst
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Computer Science Department, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Computational Medicine Department, University of California, Los Angeles, Los Angeles, CA 90095, USA
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4
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Sokolova V, Sarkar S, Tan D. Histone variants and chromatin structure, update of advances. Comput Struct Biotechnol J 2022; 21:299-311. [PMID: 36582440 PMCID: PMC9764139 DOI: 10.1016/j.csbj.2022.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 12/01/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
Histone proteins are highly conserved among all eukaryotes. They have two important functions in the cell: to package the genomic DNA and to regulate gene accessibility. Fundamental to these functions is the ability of histone proteins to interact with DNA and to form the nucleoprotein complex called chromatin. One of the mechanisms the cells use to regulate chromatin and gene expression is through replacing canonical histones with their variants at specific loci to achieve functional consequence. Recent cryo-electron microscope (cryo-EM) studies of chromatin containing histone variants reveal new details that shed light on how variant-specific features influence the structures and functions of chromatin. In this article, we review the current state of knowledge on histone variants biochemistry and discuss the implication of these new structural information on histone variant biology and their functions in transcription.
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5
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Dijkwel Y, Tremethick DJ. The Role of the Histone Variant H2A.Z in Metazoan Development. J Dev Biol 2022; 10:jdb10030028. [PMID: 35893123 PMCID: PMC9326617 DOI: 10.3390/jdb10030028] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/12/2022] [Accepted: 06/23/2022] [Indexed: 12/10/2022] Open
Abstract
During the emergence and radiation of complex multicellular eukaryotes from unicellular ancestors, transcriptional systems evolved by becoming more complex to provide the basis for this morphological diversity. The way eukaryotic genomes are packaged into a highly complex structure, known as chromatin, underpins this evolution of transcriptional regulation. Chromatin structure is controlled by a variety of different epigenetic mechanisms, including the major mechanism for altering the biochemical makeup of the nucleosome by replacing core histones with their variant forms. The histone H2A variant H2A.Z is particularly important in early metazoan development because, without it, embryos cease to develop and die. However, H2A.Z is also required for many differentiation steps beyond the stage that H2A.Z-knockout embryos die. H2A.Z can facilitate the activation and repression of genes that are important for pluripotency and differentiation, and acts through a variety of different molecular mechanisms that depend upon its modification status, its interaction with histone and nonhistone partners, and where it is deposited within the genome. In this review, we discuss the current knowledge about the different mechanisms by which H2A.Z regulates chromatin function at various developmental stages and the chromatin remodeling complexes that determine when and where H2A.Z is deposited.
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6
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Grau-Bové X, Navarrete C, Chiva C, Pribasnig T, Antó M, Torruella G, Galindo LJ, Lang BF, Moreira D, López-Garcia P, Ruiz-Trillo I, Schleper C, Sabidó E, Sebé-Pedrós A. A phylogenetic and proteomic reconstruction of eukaryotic chromatin evolution. Nat Ecol Evol 2022; 6:1007-1023. [PMID: 35680998 PMCID: PMC7613034 DOI: 10.1038/s41559-022-01771-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 04/21/2022] [Indexed: 02/06/2023]
Abstract
Histones and associated chromatin proteins have essential functions in eukaryotic genome organization and regulation. Despite this fundamental role in eukaryotic cell biology, we lack a phylogenetically-comprehensive understanding of chromatin evolution. Here, we combine comparative proteomics and genomics analysis of chromatin in eukaryotes and archaea. Proteomics uncovers the existence of histone post-translational modifications in Archaea. However, archaeal histone modifications are scarce, in contrast with the highly conserved and abundant marks we identify across eukaryotes. Phylogenetic analysis reveals that chromatin-associated catalytic functions (e.g., methyltransferases) have pre-eukaryotic origins, whereas histone mark readers and chaperones are eukaryotic innovations. We show that further chromatin evolution is characterized by expansion of readers, including capture by transposable elements and viruses. Overall, our study infers detailed evolutionary history of eukaryotic chromatin: from its archaeal roots, through the emergence of nucleosome-based regulation in the eukaryotic ancestor, to the diversification of chromatin regulators and their hijacking by genomic parasites.
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Affiliation(s)
- Xavier Grau-Bové
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Cristina Navarrete
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | | | - Thomas Pribasnig
- Department of Functional and Evolutionary Ecology, Archaea Biology Unit, University of Vienna, Vienna, Austria
| | - Meritxell Antó
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Spain
| | - Guifré Torruella
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Luis Javier Galindo
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Bernd Franz Lang
- Robert Cedergren Centre in Bioinformatics and Genomics, Department of Biochemistry, Université de Montréal, Montréal, Quebec, Canada
| | - David Moreira
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Purificación López-Garcia
- Unité d'Ecologie Systématique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | - Christa Schleper
- Department of Functional and Evolutionary Ecology, Archaea Biology Unit, University of Vienna, Vienna, Austria
| | - Eduard Sabidó
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Arnau Sebé-Pedrós
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain.
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7
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Mammalian PERIOD2 regulates H2A.Z incorporation in chromatin to orchestrate circadian negative feedback. Nat Struct Mol Biol 2022; 29:549-562. [PMID: 35606517 DOI: 10.1038/s41594-022-00777-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 04/11/2022] [Indexed: 11/08/2022]
Abstract
Mammalian circadian oscillators are built on a feedback loop in which the activity of the transcription factor CLOCK-BMAL1 is repressed by the PER-CRY complex. Here, we show that murine Per-/- fibroblasts display aberrant nucleosome occupancy around transcription start sites (TSSs) and at promoter-proximal and distal CTCF sites due to impaired histone H2A.Z deposition. Knocking out H2A.Z mimicked the Per null chromatin state and disrupted cellular rhythms. We found that endogenous mPER2 complexes retained CTCF as well as the specific H2A.Z-deposition chaperone YL1-a component of the ATP-dependent remodeler SRCAP and p400-TIP60 complex. While depleting YL1 or mutating chaperone-binding sites on H2A.Z lengthened the circadian period, H2A.Z deletion abrogated BMAL1 chromatin recruitment and promoted its proteasomal degradation. We propose that a PER2-mediated H2A.Z deposition pathway (1) compacts CLOCK-BMAL1 binding sites to establish negative feedback, (2) organizes circadian chromatin landscapes using CTCF and (3) bookmarks genomic loci for BMAL1 binding to impinge on the positive arm of the subsequent cycle.
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8
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Yang Y, Zhang L, Xiong C, Chen J, Wang L, Wen Z, Yu J, Chen P, Xu Y, Jin J, Cai Y, Li G. HIRA complex presets transcriptional potential through coordinating depositions of the histone variants H3.3 and H2A.Z on the poised genes in mESCs. Nucleic Acids Res 2022; 50:191-206. [PMID: 34893908 PMCID: PMC8754660 DOI: 10.1093/nar/gkab1221] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 11/26/2021] [Accepted: 11/30/2021] [Indexed: 12/21/2022] Open
Abstract
Histone variants have been implicated in regulating chromatin dynamics and genome functions. Previously, we have shown that histone variant H3.3 actively marks enhancers and cooperates with H2A.Z at promoters to prime the genes into a poised state in mouse embryonic stem cells (mESCs). However, how these two important histone variants collaboratively function in this process still remains elusive. In this study, we found that depletion of different components of HIRA complex, a specific chaperone of H3.3, results in significant decreases of H2A.Z enrichment at genome scale. In addition, CUT&Tag data revealed a genomic colocalization between HIRA complex and SRCAP complex. In vivo and in vitro biochemical assays verified that HIRA complex could interact with SRCAP complex through the Hira subunit. Furthermore, our chromatin accessibility and transcription analyses demonstrated that HIRA complex contributed to preset a defined chromatin feature around TSS region for poising gene transcription. In summary, our results unveiled that while regulating the H3.3 incorporation in the regulatory regions, HIRA complex also collaborates with SRCAP to deposit H2A.Z onto the promoters, which cooperatively determines the transcriptional potential of the poised genes in mESCs.
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Affiliation(s)
- Yang Yang
- School of Life Sciences, Jilin University, 2699 Qianjin Street, Changchun 130012, China
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Liwei Zhang
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Chaoyang Xiong
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jun Chen
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Department of Immunology, School of Basic Medical Sciences, Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100069, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Li Wang
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Zengqi Wen
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Juan Yu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Ping Chen
- Department of Immunology, School of Basic Medical Sciences, Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100069, China
| | - Yanhui Xu
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Jingji Jin
- School of Life Sciences, Jilin University, 2699 Qianjin Street, Changchun 130012, China
- National Engineering Laboratory for AIDS Vaccine, Jilin University, 2699 Qianjin Street, Changchun 130012, China
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yong Cai
- School of Life Sciences, Jilin University, 2699 Qianjin Street, Changchun 130012, China
- National Engineering Laboratory for AIDS Vaccine, Jilin University, 2699 Qianjin Street, Changchun 130012, China
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Guohong Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing, China
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9
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A Comprehensive Toolbox to Analyze Enhancer-Promoter Functions. Methods Mol Biol 2021. [PMID: 34382181 DOI: 10.1007/978-1-0716-1597-3_1] [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: 11/08/2023]
Abstract
Knowledge in gene transcription and chromatin regulation has been intensely studied for decades, but thanks to next-generation sequencing (NGS) techniques there has been a major leap forward in the last few years. Historically, identification of specific enhancer elements has led to the identification of master transcription factors (TFs) in the 1990s. Genetic and biochemical experiments have identified the key regulators controlling RNA polymerase II (RNAPII) transcription and structurally analyses have elucidated detailed mechanisms. NGS and the development of chromatin immunoprecipitation (ChIP) have accelerated the gain of knowledge in the recent years. By now, we have a dazzling wealth of techniques that are currently used to put gene expression into a genome-wide context. This book is an attempt to assemble useful protocols for many researchers within and nearby research areas. In general, these innovative techniques focus on enhancer and promoter studies. The techniques should also be of interest for related fields such as DNA repair and replication.
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10
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Jiang X, Wen J, Paver E, Wu Y, Sun G, Bullman A, Dahlstrom J, Tremethick DJ, Soboleva TA. H2A.B is a cancer/testis factor involved in the activation of ribosome biogenesis in Hodgkin lymphoma. EMBO Rep 2021; 22:e52462. [PMID: 34350706 PMCID: PMC8339673 DOI: 10.15252/embr.202152462] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 06/02/2021] [Accepted: 06/15/2021] [Indexed: 12/12/2022] Open
Abstract
Testis-specific regulators of chromatin function are commonly ectopically expressed in human cancers, but their roles are poorly understood. Examination of 81 primary Hodgkin lymphoma (HL) samples showed that the ectopic expression of the eutherian testis-specific histone variant H2A.B is an inherent feature of HL. In experiments using two HL cell lines derived from different subtypes of HL, H2A.B knockdown inhibited cell proliferation. H2A.B was enriched in both nucleoli of these HL cell lines and primary HL samples. We found that H2A.B enhanced ribosomal DNA (rDNA) transcription, was enriched at the rDNA promoter and transcribed regions, and interacted with RNA Pol I. Depletion of H2A.B caused the loss of RNA Pol I from rDNA chromatin. Remarkably, H2A.B was also required for high levels of ribosomal protein gene expression being located at the transcriptional start site and within the gene body. H2A.B knockdown reduced gene body chromatin accessibility of active RNA Pol II genes concurrent with a decrease in transcription. Taken together, our data show that in HL H2A.B has acquired a new function, the ability to increase ribosome biogenesis.
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Affiliation(s)
- Xuanzhao Jiang
- The John Curtin School of Medical ResearchThe Australian National UniversityCanberraACTAustralia
| | - Jiayu Wen
- The John Curtin School of Medical ResearchThe Australian National UniversityCanberraACTAustralia
| | - Elizabeth Paver
- Department of Tissue Pathology and Diagnostic OncologyRoyal Prince Alfred HospitalSydneyNSWAustralia
| | - Yu‐Huan Wu
- The John Curtin School of Medical ResearchThe Australian National UniversityCanberraACTAustralia
- Present address:
IQVIA Solutions Taiwan Ltd.Taipei CityTaiwan
| | - Gege Sun
- The John Curtin School of Medical ResearchThe Australian National UniversityCanberraACTAustralia
- Present address:
Department of Applied Biology and Chemical Technology and State Key Laboratory of Chemical Biology and Drug DiscoveryHong Kong Polytechnic UniversityHong KongChina
| | - Amanda Bullman
- Department of Anatomical PathologyACT PathologyThe Canberra HospitalCanberraACTAustralia
| | - Jane E Dahlstrom
- Department of Anatomical PathologyACT PathologyThe Canberra HospitalCanberraACTAustralia
- Australian National University Medical SchoolThe Australian National UniversityCanberraACTAustralia
| | - David J Tremethick
- The John Curtin School of Medical ResearchThe Australian National UniversityCanberraACTAustralia
| | - Tatiana A Soboleva
- The John Curtin School of Medical ResearchThe Australian National UniversityCanberraACTAustralia
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11
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Gamarra N, Narlikar GJ. Collaboration through chromatin: motors of transcription and chromatin structure. J Mol Biol 2021; 433:166876. [PMID: 33556407 PMCID: PMC8989640 DOI: 10.1016/j.jmb.2021.166876] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 01/09/2023]
Abstract
Packaging of the eukaryotic genome into chromatin places fundamental physical constraints on transcription. Clarifying how transcription operates within these constraints is essential to understand how eukaryotic gene expression programs are established and maintained. Here we review what is known about the mechanisms of transcription on chromatin templates. Current models indicate that transcription through chromatin is accomplished by the combination of an inherent nucleosome disrupting activity of RNA polymerase and the action of ATP-dependent chromatin remodeling motors. Collaboration between these two types of molecular motors is proposed to occur at all stages of transcription through diverse mechanisms. Further investigation of how these two motors combine their basic activities is essential to clarify the interdependent relationship between genome structure and transcription.
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Affiliation(s)
- Nathan Gamarra
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States; TETRAD Graduate Program, University of California, San Francisco, San Francisco, United States
| | - Geeta J Narlikar
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States.
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12
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Cole L, Kurscheid S, Nekrasov M, Domaschenz R, Vera DL, Dennis JH, Tremethick DJ. Multiple roles of H2A.Z in regulating promoter chromatin architecture in human cells. Nat Commun 2021; 12:2524. [PMID: 33953180 PMCID: PMC8100287 DOI: 10.1038/s41467-021-22688-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 03/25/2021] [Indexed: 01/02/2023] Open
Abstract
Chromatin accessibility of a promoter is fundamental in regulating transcriptional activity. The histone variant H2A.Z has been shown to contribute to this regulation, but its role has remained poorly understood. Here, we prepare high-depth maps of the position and accessibility of H2A.Z-containing nucleosomes for all human Pol II promoters in epithelial, mesenchymal and isogenic cancer cell lines. We find that, in contrast to the prevailing model, many different types of active and inactive promoter structures are observed that differ in their nucleosome organization and sensitivity to MNase digestion. Key aspects of an active chromatin structure include positioned H2A.Z MNase resistant nucleosomes upstream or downstream of the TSS, and a MNase sensitive nucleosome at the TSS. Furthermore, the loss of H2A.Z leads to a dramatic increase in the accessibility of transcription factor binding sites. Collectively, these results suggest that H2A.Z has multiple and distinct roles in regulating gene expression dependent upon its location in a promoter.
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Affiliation(s)
- Lauren Cole
- College of Arts and Sciences, Department of Biological Sciences, Florida State University, Tallahassee, FL, USA
| | - Sebastian Kurscheid
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Maxim Nekrasov
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Renae Domaschenz
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Daniel L Vera
- College of Arts and Sciences, Department of Biological Sciences, Florida State University, Tallahassee, FL, USA
- Department of Genetics, Blavatnik Institute, Paul F. Glenn Center for Biology of Aging Research, Harvard Medical School, Boston, MA, USA
| | - Jonathan H Dennis
- College of Arts and Sciences, Department of Biological Sciences, Florida State University, Tallahassee, FL, USA.
| | - David J Tremethick
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia.
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13
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Her YR, Wang L, Chepelev I, Manterola M, Berkovits B, Cui K, Zhao K, Wolgemuth DJ. Genome-wide chromatin occupancy of BRDT and gene expression analysis suggest transcriptional partners and specific epigenetic landscapes that regulate gene expression during spermatogenesis. Mol Reprod Dev 2021; 88:141-157. [PMID: 33469999 DOI: 10.1002/mrd.23449] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/13/2020] [Accepted: 12/27/2020] [Indexed: 11/09/2022]
Abstract
BRDT, a member of the BET family of double bromodomain-containing proteins, is essential for spermatogenesis in the mouse and has been postulated to be a key regulator of transcription in meiotic and post-meiotic cells. To understand the function of BRDT in these processes, we first characterized the genome-wide distribution of the BRDT binding sites, in particular within gene units, by ChIP-Seq analysis of enriched fractions of pachytene spermatocytes and round spermatids. In both cell types, BRDT binding sites were mainly located in promoters, first exons, and introns of genes. BRDT binding sites in promoters overlapped with several histone modifications and histone variants associated with active transcription, and were enriched for consensus sequences for specific transcription factors, including MYB, RFX, ETS, and ELF1 in pachytene spermatocytes, and JunD, c-Jun, CRE, and RFX in round spermatids. Subsequent integration of the ChIP-seq data with available transcriptome data revealed that stage-specific gene expression programs are associated with BRDT binding to their gene promoters, with most of the BDRT-bound genes being upregulated. Gene Ontology analysis further identified unique sets of genes enriched in diverse biological processes essential for meiosis and spermiogenesis between the two cell types, suggesting distinct developmentally stage-specific functions for BRDT. Taken together, our data suggest that BRDT cooperates with different transcription factors at distinctive chromatin regions within gene units to regulate diverse downstream target genes that function in male meiosis and spermiogenesis.
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Affiliation(s)
- Yoon Ra Her
- Department of Genetics & Development, Columbia University Medical Center, New York, New York, USA
| | - Li Wang
- Department of Genetics & Development, Columbia University Medical Center, New York, New York, USA
| | - Iouri Chepelev
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.,Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Marcia Manterola
- Human Genetics Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Binyamin Berkovits
- Department of Genetics & Development, Columbia University Medical Center, New York, New York, USA
| | - Kairong Cui
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Keji Zhao
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Debra J Wolgemuth
- Department of Genetics & Development, Columbia University Medical Center, New York, New York, USA.,Department Obstetrics & Gynecology, Columbia University Medical Center, New York, New York, USA.,Institute of Human Nutrition, Columbia University Medical Center, New York, New York, USA.,Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, New York, USA
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14
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Lone IN, Sengez B, Hamiche A, Dimitrov S, Alotaibi H. The Role of Histone Variants in the Epithelial-To-Mesenchymal Transition. Cells 2020; 9:cells9112499. [PMID: 33213091 PMCID: PMC7698467 DOI: 10.3390/cells9112499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/13/2020] [Accepted: 11/14/2020] [Indexed: 11/16/2022] Open
Abstract
The epithelial-to-mesenchymal transition (EMT) is a physiological process activated during early embryogenesis, which continues to shape tissues and organs later on. It is also hijacked by tumor cells during metastasis. The regulation of EMT has been the focus of many research groups culminating in the last few years and resulting in an elaborate transcriptional network buildup. However, the implication of epigenetic factors in the control of EMT is still in its infancy. Recent discoveries pointed out that histone variants, which are key epigenetic players, appear to be involved in EMT control. This review summarizes the available data on histone variants' function in EMT that would contribute to a better understanding of EMT itself and EMT-related diseases.
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Affiliation(s)
- Imtiaz Nisar Lone
- Izmir Biomedicine and Genome Center, Izmir 35340, Turkey; (I.N.L.); (B.S.); (S.D.)
| | - Burcu Sengez
- Izmir Biomedicine and Genome Center, Izmir 35340, Turkey; (I.N.L.); (B.S.); (S.D.)
- Izmir International Biomedicine and Genome Institute, Dokuz Eylül University, Izmir 35340, Turkey
| | - Ali Hamiche
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), 1 rue Laurent Fries, 67400 Illkirch, France;
| | - Stefan Dimitrov
- Izmir Biomedicine and Genome Center, Izmir 35340, Turkey; (I.N.L.); (B.S.); (S.D.)
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé-Allée des Alpes, 38700 La Tronche, France
| | - Hani Alotaibi
- Izmir Biomedicine and Genome Center, Izmir 35340, Turkey; (I.N.L.); (B.S.); (S.D.)
- Izmir International Biomedicine and Genome Institute, Dokuz Eylül University, Izmir 35340, Turkey
- Correspondence: ; Tel.: +90-232-299-4100 (ext. 5071)
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15
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Chen Z, Zehraoui E, Atanasoff-Kardjalieff AK, Strauss J, Studt L, Ponts N. Effect of H2A.Z deletion is rescued by compensatory mutations in Fusarium graminearum. PLoS Genet 2020; 16:e1009125. [PMID: 33091009 PMCID: PMC7608984 DOI: 10.1371/journal.pgen.1009125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 11/03/2020] [Accepted: 09/21/2020] [Indexed: 12/31/2022] Open
Abstract
Fusarium head blight is a destructive disease of grains resulting in reduced yields and contamination of grains with mycotoxins worldwide; Fusarium graminearum is its major causal agent. Chromatin structure changes play key roles in regulating mycotoxin biosynthesis in filamentous fungi. Using a split-marker approach in three F. graminearum strains INRA156, INRA349 and INRA812 (PH-1), we knocked out the gene encoding H2A.Z, a ubiquitous histone variant reported to be involved in a diverse range of biological processes in yeast, plants and animals, but rarely studied in filamentous fungi. All ΔH2A.Z mutants exhibit defects in development including radial growth, sporulation, germination and sexual reproduction, but with varying degrees of severity between them. Heterogeneity of osmotic and oxidative stress response as well as mycotoxin production was observed in ΔH2A.Z strains. Adding-back wild-type H2A.Z in INRA349ΔH2A.Z could not rescue the phenotypes. Whole genome sequencing revealed that, although H2A.Z has been removed from the genome and the deletion cassette is inserted at H2A.Z locus only, mutations occur at other loci in each mutant regardless of the genetic background. Genes affected by these mutations encode proteins involved in chromatin remodeling, such as the helicase Swr1p or an essential subunit of the histone deacetylase Rpd3S, and one protein of unknown function. These observations suggest that H2A.Z and the genes affected by such mutations are part or the same genetic interaction network. Our results underline the genetic plasticity of F. graminearum facing detrimental gene perturbation. These findings suggest that intergenic suppressions rescue deleterious phenotypes in ΔH2A.Z strains, and that H2A.Z may be essential in F. graminearum. This assumption is further supported by the fact that H2A.Z deletion failed in another Fusarium spp., i.e., the rice pathogen Fusarium fujikuroi.
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Affiliation(s)
| | | | - Anna K. Atanasoff-Kardjalieff
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Vienna, Austria
| | - Joseph Strauss
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Vienna, Austria
| | - Lena Studt
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Vienna, Austria
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16
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Abstract
Chromatin is a highly dynamic structure that closely relates with gene expression in eukaryotes. ATP-dependent chromatin remodelling, histone post-translational modification and DNA methylation are the main ways that mediate such plasticity. The histone variant H2A.Z is frequently encountered in eukaryotes, and can be deposited or removed from nucleosomes by chromatin remodelling complex SWR1 or INO80, respectively, leading to altered chromatin state. H2A.Z has been found to be involved in a diverse range of biological processes, including genome stability, DNA repair and transcriptional regulation. Due to their formidable production of secondary metabolites, filamentous fungi play outstanding roles in pharmaceutical production, food safety and agriculture. During the last few years, chromatin structural changes were proven to be a key factor associated with secondary metabolism in fungi. However, studies on the function of H2A.Z are scarce. Here, we summarize current knowledge of H2A.Z functions with a focus on filamentous fungi. We propose that H2A.Z is a potential target involved in the regulation of secondary metabolite biosynthesis by fungi.
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17
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Short Histone H2A Variants: Small in Stature but not in Function. Cells 2020; 9:cells9040867. [PMID: 32252453 PMCID: PMC7226823 DOI: 10.3390/cells9040867] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/24/2020] [Accepted: 03/31/2020] [Indexed: 12/19/2022] Open
Abstract
The dynamic packaging of DNA into chromatin regulates all aspects of genome function by altering the accessibility of DNA and by providing docking pads to proteins that copy, repair and express the genome. Different epigenetic-based mechanisms have been described that alter the way DNA is organised into chromatin, but one fundamental mechanism alters the biochemical composition of a nucleosome by substituting one or more of the core histones with their variant forms. Of the core histones, the largest number of histone variants belong to the H2A class. The most divergent class is the designated “short H2A variants” (H2A.B, H2A.L, H2A.P and H2A.Q), so termed because they lack a H2A C-terminal tail. These histone variants appeared late in evolution in eutherian mammals and are lineage-specific, being expressed in the testis (and, in the case of H2A.B, also in the brain). To date, most information about the function of these peculiar histone variants has come from studies on the H2A.B and H2A.L family in mice. In this review, we describe their unique protein characteristics, their impact on chromatin structure, and their known functions plus other possible, even non-chromatin, roles in an attempt to understand why these peculiar histone variants evolved in the first place.
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18
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Exploring histone loading on HIV DNA reveals a dynamic nucleosome positioning between unintegrated and integrated viral genome. Proc Natl Acad Sci U S A 2020; 117:6822-6830. [PMID: 32161134 PMCID: PMC7104181 DOI: 10.1073/pnas.1913754117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The biology of HIV DNA, from its synthesis to its integration into the host genome, remains poorly understood. Here we show that in the nucleus, histones are rapidly loaded on newly synthesized unintegrated HIV DNA. Interestingly, the chromatin architecture around the HIV long terminal repeat (LTR) is different in unintegrated and integrated HIV DNA. Specifically, a nucleosome present only on the DNase hypersensitive site of unintegrated HIV DNA contributes to the transcriptional silencing of unintegrated HIV DNA by preventing RNAPII recruitment. The aim of the present study was to understand the biology of unintegrated HIV-1 DNA and reveal the mechanisms involved in its transcriptional silencing. We found that histones are loaded on HIV-1 DNA after its nuclear import and before its integration in the host genome. Nucleosome positioning analysis along the unintegrated and integrated viral genomes revealed major differences in nucleosome density and position. Indeed, in addition to the well-known nucleosomes Nuc0, Nuc1, and Nuc2 loaded on integrated HIV-1 DNA, we also found NucDHS, a nucleosome that covers the DNase hypersensitive site, in unintegrated viral DNA. In addition, unintegrated viral DNA-associated Nuc0 and Nuc2 were positioned slightly more to the 5′ end relative to their position in integrated DNA. The presence of NucDHS in the proximal region of the long terminal repeat (LTR) promoter was associated with the absence of RNAPII and of the active histone marks H3K4me3 and H3ac at the LTR. Conversely, analysis of integrated HIV-1 DNA showed a loss of NucDHS, loading of RNAPII, and enrichment in active histone marks within the LTR. We propose that unintegrated HIV-1 DNA adopts a repressive chromatin structure that competes with the transcription machinery, leading to its silencing.
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19
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Ryan DP, Tremethick DJ. The interplay between H2A.Z and H3K9 methylation in regulating HP1α binding to linker histone-containing chromatin. Nucleic Acids Res 2019; 46:9353-9366. [PMID: 30007360 PMCID: PMC6182156 DOI: 10.1093/nar/gky632] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/04/2018] [Indexed: 12/14/2022] Open
Abstract
One of the most intensively studied chromatin binding factors is HP1α. HP1α is associated with silenced, heterochromatic regions of the genome and binds to H3K9me3. While H3K9me3 is necessary for HP1α recruitment to heterochromatin, it is becoming apparent that it is not sufficient suggesting that additional factors are involved. One candidate proposed as a potential regulator of HP1α recruitment is the linker histone H1.4. Changes to the underlying make-up of chromatin, such as the incorporation of the histone variant H2A.Z, has also been linked with regulating HP1 binding to chromatin. Here, we rigorously dissected the effects of H1.4, H2A.Z and H3K9me3 on the nucleosome binding activity of HP1α in vitro employing arrays, mononucleosomes and nucleosome core particles. Unexpectedly, histone H1.4 impedes the binding of HP1α but strikingly, this inhibition is partially relieved by the incorporation of both H2A.Z and H3K9me3 but only in the context of arrays or nucleosome core particles. Our data suggests that there are two modes of interaction of HP1α with nucleosomes. The first primary mode is through interactions with linker DNA. However, when linker DNA is missing or occluded by linker histones, HP1α directly interacts with the nucleosome core and this interaction is enhanced by H2A.Z with H3K9me3.
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Affiliation(s)
- Daniel P Ryan
- Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, ACT 2601, Australia
| | - David J Tremethick
- Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, ACT 2601, Australia
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20
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Giaimo BD, Ferrante F, Herchenröther A, Hake SB, Borggrefe T. The histone variant H2A.Z in gene regulation. Epigenetics Chromatin 2019; 12:37. [PMID: 31200754 PMCID: PMC6570943 DOI: 10.1186/s13072-019-0274-9] [Citation(s) in RCA: 173] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 04/23/2019] [Indexed: 01/04/2023] Open
Abstract
The histone variant H2A.Z is involved in several processes such as transcriptional control, DNA repair, regulation of centromeric heterochromatin and, not surprisingly, is implicated in diseases such as cancer. Here, we review the recent developments on H2A.Z focusing on its role in transcriptional activation and repression. H2A.Z, as a replication-independent histone, has been studied in several model organisms and inducible mammalian model systems. Its loading machinery and several modifying enzymes have been recently identified, and some of the long-standing discrepancies in transcriptional activation and/or repression are about to be resolved. The buffering functions of H2A.Z, as supported by genome-wide localization and analyzed in several dynamic systems, are an excellent example of transcriptional control. Posttranslational modifications such as acetylation and ubiquitination of H2A.Z, as well as its specific binding partners, are in our view central players in the control of gene expression. Understanding the key-mechanisms in either turnover or stabilization of H2A.Z-containing nucleosomes as well as defining the H2A.Z interactome will pave the way for therapeutic applications in the future.
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Affiliation(s)
| | - Francesca Ferrante
- Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392, Giessen, Germany
| | - Andreas Herchenröther
- Institute for Genetics, University of Giessen, Heinrich-Buff-Ring 58-62, 35392, Giessen, Germany
| | - Sandra B Hake
- Institute for Genetics, University of Giessen, Heinrich-Buff-Ring 58-62, 35392, Giessen, Germany
| | - Tilman Borggrefe
- Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392, Giessen, Germany.
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21
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Hamad MF. Quantification of histones and protamines mRNA transcripts in sperms of infertile couples and their impact on sperm's quality and chromatin integrity. Reprod Biol 2019; 19:6-13. [PMID: 30876814 DOI: 10.1016/j.repbio.2019.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 02/17/2019] [Accepted: 03/02/2019] [Indexed: 11/16/2022]
Abstract
The proper transition of histones to protamine during spermiogenesis is critical for male fertility. This study aimed to quantify the levels of histones and protamines mRNA in sperms of infertile couples and their possible effect on the sperm's quality and chromatin integrity. Spermatozoa from 53 normal and 75 patients were enrolled in this study. Histones and Protamine mRNAs were extracted, reverse-transcribed and applied to real-time quantitative PCR. Chromomycin A3 staining was used to assess protamination and chromatin integrity, and Eosin-Nigrosine-Test and HOS-Test was used to evaluate the sperm's vitality and membrane integrity respectively. Levels of histones H2A and H2B mRNA in patient's sperms were significantly (p < 0.01) higher than that of normal (31.22 ± 2.91, 30.03 ± 2.05 vs. 25.62 ± 1.98, 27.23 ± 3.04, respectively). Protamine PRM2 mRNA in patient's sperms (20.55 ± 2.01) was significantly lower than in normal (21.73 ± 2.64, p < 0.01). The PRM1/PRM2 and H2A/H2B mRNAs ratios were significantly higher (p < 0.01) in patients than normal (1.02 ± 0.10, 1.04 ± 0.07 vs. 0.98 ± 0.06, 0.94 ± 0.08 respectively). Also, the sperm's nuclear histones to protamines transcripts ((H2A + H2B)/(PRM1 + PRM2)) ratios of patients (1.49 ± 0.16) was significantly higher (p < 0.01) than that of normal (1.25 ± 0.15). Histone/protamine transcripts [((H2A + H2B)/(PRM1 + PRM2)) mRNAs ratios] were negatively correlated (p < 0.05) with sperm's count, total count, motility, progressive motility, normal morphology, membrane integrity and positively with chromatin decondensation. The data suggests that histones/protamines mRNAs ratios are important for a sperm's quality and therefore could be used as predictors for male infertility. Also, validation study may be required to confirm the study conclusion.
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Affiliation(s)
- Mohammed Faiz Hamad
- Department of Basic Sciences, College of Science and Health Professions, King Saud Bin Abdulaziz University for Health Sciences, Jeddah, Riyadh, Saudi Arabia; IVF & Andrology Laboratory, Department of Obstetrics and Gynecology, Saarland University, Homburg, Saar, Germany.
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22
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Yerra VG, Advani A. Histones and heart failure in diabetes. Cell Mol Life Sci 2018; 75:3193-3213. [PMID: 29934664 PMCID: PMC6063320 DOI: 10.1007/s00018-018-2857-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 06/12/2018] [Accepted: 06/15/2018] [Indexed: 12/22/2022]
Abstract
Although heart failure is now accepted as being a major long-term complication of diabetes, many of the recent advances in our understanding of the pathobiology of diabetes complications have come about through the study of more traditional microvascular or macrovascular diseases. This has been the case, for example, in the evolving field of the epigenetics of diabetes complications and, in particular, the post-translational modification of histone proteins. However, histone modifications also occur in human heart failure and their perturbation also occurs in diabetic hearts. Here, we review the principal histone modifications and their enzymatic writers and erasers that have been studied to date; we discuss what is currently known about their roles in heart failure and in the diabetic heart; we draw on lessons learned from the studies of microvascular and macrovascular complications; and we speculate that therapeutically manipulating histone modifications may alter the natural history of heart failure in diabetes.
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Affiliation(s)
- Veera Ganesh Yerra
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, 6-151, 61 Queen Street East, Toronto, ON, M5C 2T2, Canada
| | - Andrew Advani
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, 6-151, 61 Queen Street East, Toronto, ON, M5C 2T2, Canada.
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23
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Zhao H, Zhang F, Guo M, Xing Y, Liu G, Zhao X, Cai L. The affinity of DNA sequences containing R5Y5 motif and TA repeats with 10.5-bp periodicity to histone octamer in vitro. J Biomol Struct Dyn 2018; 37:1935-1943. [PMID: 30044196 DOI: 10.1080/07391102.2018.1477621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Nucleosome positioning along the genome is partially determined by the intrinsic DNA sequence preferences on histone. RRRRRYYYYY (R5Y5, R = Purine and Y = Pyrimidine) motif in nucleosome DNA, which was presented based on several theoretical models by Trifonov et al., might be a facilitating sequence pattern for nucleosome assembly. However, there is not a high conformity experimental evidence to support the concept that R5Y5 motif is a key element for the determination of nucleosome positioning. In this work, the ability of the canonical, H2A.Z- and H3.3-containing octamers to assemble nucleosome on DNA templates containing R5Y5 motif and TA repeats within 10.5-bp periodicity was investigated by using salt-dialysis method in vitro. The results showed that the10.5-bp periodical distributions of both R5Y5 motif and TA repeats along DNA templates can significantly promote canonical nucleosome assembly and may be key sequence factors for canonical nucleosome assembly. Compared with TA repeats within 10.5-bp periodicity, R5Y5 motif in DNA templates did not elevate H2A.Z- and H3.3-containing nucleosome formation efficiency in vitro. This result indicates that R5Y5 motif probably isn't a pivotal factor to regulate nucleosome assembly on histone variants. It is speculated that the regulatory mechanism of nucleosome assembly is different between canonical and variant histone. These conclusions can provide a deeper insight on the mechanism of nucleosome positioning. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Hongyu Zhao
- a School of Life Science and Technology , Inner Mongolia University of Science and Technology , Baotou , China.,b Inner Mongolia Key Laboratory of Functional Genome Bioinformatics , Inner Mongolia University of Science and Technology , Baotou , China
| | - Fenghui Zhang
- a School of Life Science and Technology , Inner Mongolia University of Science and Technology , Baotou , China
| | - Mingxin Guo
- a School of Life Science and Technology , Inner Mongolia University of Science and Technology , Baotou , China
| | - Yongqiang Xing
- a School of Life Science and Technology , Inner Mongolia University of Science and Technology , Baotou , China.,b Inner Mongolia Key Laboratory of Functional Genome Bioinformatics , Inner Mongolia University of Science and Technology , Baotou , China
| | - Guoqing Liu
- a School of Life Science and Technology , Inner Mongolia University of Science and Technology , Baotou , China.,b Inner Mongolia Key Laboratory of Functional Genome Bioinformatics , Inner Mongolia University of Science and Technology , Baotou , China
| | - Xiujuan Zhao
- a School of Life Science and Technology , Inner Mongolia University of Science and Technology , Baotou , China.,b Inner Mongolia Key Laboratory of Functional Genome Bioinformatics , Inner Mongolia University of Science and Technology , Baotou , China
| | - Lu Cai
- a School of Life Science and Technology , Inner Mongolia University of Science and Technology , Baotou , China.,b Inner Mongolia Key Laboratory of Functional Genome Bioinformatics , Inner Mongolia University of Science and Technology , Baotou , China
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24
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Hoghoughi N, Barral S, Vargas A, Rousseaux S, Khochbin S. Histone variants: essential actors in male genome programming. J Biochem 2018; 163:97-103. [PMID: 29165574 DOI: 10.1093/jb/mvx079] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 10/13/2017] [Indexed: 02/03/2023] Open
Abstract
Prior to its transmission to the offspring, the male genome has to be tightly compacted. A genome-scale histone eviction and the subsequent repackaging of DNA by protamines (Prms) direct this essential genome condensation step. The requirement for male germ cells to undergo such a dramatic and unique genome reorganization explains why these cells express the largest number of histone variants, including many testis-specific ones. Indeed, an open chromatin, nucleosome instability and a facilitated process of histone disassembly are direct consequences of the presence of these histone variants in the chromatin of male germ cells. These histone-induced changes in chromatin first control a stage-specific gene expression program and then directly mediate the histone-to-Prm transition process. This review aims at summarizing and discussing a series of recent functional studies of male germ cell histone variants with a focus on their impact on the process of histone eviction and male genome compaction.
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Affiliation(s)
- Naghmeh Hoghoughi
- CNRS UMR 5309, Inserm, U1209, Université Grenoble Alpes, Institut Albert Bonniot, Grenoble F-38700, France
| | - Sophie Barral
- CNRS UMR 5309, Inserm, U1209, Université Grenoble Alpes, Institut Albert Bonniot, Grenoble F-38700, France
| | - Alexandra Vargas
- CNRS UMR 5309, Inserm, U1209, Université Grenoble Alpes, Institut Albert Bonniot, Grenoble F-38700, France
| | - Sophie Rousseaux
- CNRS UMR 5309, Inserm, U1209, Université Grenoble Alpes, Institut Albert Bonniot, Grenoble F-38700, France
| | - Saadi Khochbin
- CNRS UMR 5309, Inserm, U1209, Université Grenoble Alpes, Institut Albert Bonniot, Grenoble F-38700, France
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25
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Structural Basis of Heterochromatin Formation by Human HP1. Mol Cell 2018; 69:385-397.e8. [PMID: 29336876 DOI: 10.1016/j.molcel.2017.12.011] [Citation(s) in RCA: 167] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 11/01/2017] [Accepted: 12/13/2017] [Indexed: 12/17/2022]
Abstract
Heterochromatin plays important roles in transcriptional silencing and genome maintenance by the formation of condensed chromatin structures, which determine the epigenetic status of eukaryotic cells. The trimethylation of histone H3 lysine 9 (H3K9me3), a target of heterochromatin protein 1 (HP1), is a hallmark of heterochromatin formation. However, the mechanism by which HP1 folds chromatin-containing H3K9me3 into a higher-order structure has not been elucidated. Here we report the three-dimensional structure of the H3K9me3-containing dinucleosomes complexed with human HP1α, HP1β, and HP1γ, determined by cryogenic electron microscopy with a Volta phase plate. In the structures, two H3K9me3 nucleosomes are bridged by a symmetric HP1 dimer. Surprisingly, the linker DNA between the nucleosomes does not directly interact with HP1, thus allowing nucleosome remodeling by the ATP-utilizing chromatin assembly and remodeling factor (ACF). The structure depicts the fundamental architecture of heterochromatin.
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26
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Madakashira B, Corbett L, Zhang C, Paoli P, Casement JW, Mann J, Sadler KC, Mann DA. Variant Histone H2afv reprograms DNA methylation during early zebrafish development. Epigenetics 2017; 12:811-824. [PMID: 29099280 PMCID: PMC5739095 DOI: 10.1080/15592294.2017.1359382] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The DNA methylome is re-patterned during discrete phases of vertebrate development. In zebrafish, there are 2 waves of global DNA demethylation and re-methylation: the first occurs before gastrulation when the parental methylome is changed to the zygotic pattern and the second occurs after formation of the embryonic body axis, during organ specification. The occupancy of the histone variant H2A.Z and regions of DNA methylation are generally anti-correlated, and it has been proposed that H2A.Z restricts the boundaries of highly methylated regions. While many studies have described the dynamics of methylome changes during early zebrafish development, the factors involved in establishing the DNA methylation landscape in zebrafish embryos have not been identified. We test the hypothesis that the zebrafish ortholog of H2A.Z (H2afv) restricts DNA methylation during development. We find that, in control embryos, bulk genome methylation decreases after gastrulation, with a nadir at the bud stage, and peaks during mid-somitogenesis; by 24 hours post -fertilization, total DNA methylation levels return to those detected in gastrula. Early zebrafish embryos depleted of H2afv have significantly more bulk DNA methylation during somitogenesis, suggesting that H2afv limits methylation during this stage of development. H2afv deficient embryos are small, with multisystemic abnormalities. Genetic interaction experiments demonstrate that these phenotypes are suppressed by depletion of DNA methyltransferase 1 (Dnmt1). This work demonstrates that H2afv is essential for global DNA methylation reprogramming during early vertebrate development and that embryonic development requires crosstalk between H2afv and Dnmt1.
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Affiliation(s)
- Bhavani Madakashira
- a Program in Biology , New York University Abu Dhabi , Abu Dhabi , United Arab Emirates
| | - Laura Corbett
- b Fibrosis Group , Institute of Cellular Medicine, Newcastle University , Newcastle upon Tyne , NE24HH
| | - Chi Zhang
- a Program in Biology , New York University Abu Dhabi , Abu Dhabi , United Arab Emirates
| | - Pier Paoli
- b Fibrosis Group , Institute of Cellular Medicine, Newcastle University , Newcastle upon Tyne , NE24HH
| | - John W Casement
- c Bioinformatics Support Unit, Faculty of Medical Sciences , Newcastle University , Newcastle Upon Tyne , NE24HH
| | - Jelena Mann
- b Fibrosis Group , Institute of Cellular Medicine, Newcastle University , Newcastle upon Tyne , NE24HH
| | - Kirsten C Sadler
- a Program in Biology , New York University Abu Dhabi , Abu Dhabi , United Arab Emirates.,d Department of Medicine/Division of Liver Diseases, Department of Developmental and Regenerative Biology , Icahn School of Medicine at Mount Sinai , New York , New York
| | - Derek A Mann
- b Fibrosis Group , Institute of Cellular Medicine, Newcastle University , Newcastle upon Tyne , NE24HH
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27
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Horikoshi N, Arimura Y, Taguchi H, Kurumizaka H. Crystal structures of heterotypic nucleosomes containing histones H2A.Z and H2A. Open Biol 2017; 6:rsob.160127. [PMID: 27358293 PMCID: PMC4929947 DOI: 10.1098/rsob.160127] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 06/06/2016] [Indexed: 12/13/2022] Open
Abstract
H2A.Z is incorporated into nucleosomes located around transcription start sites and functions as an epigenetic regulator for the transcription of certain genes. During transcriptional regulation, the heterotypic H2A.Z/H2A nucleosome containing one each of H2A.Z and H2A is formed. However, previous homotypic H2A.Z nucleosome structures suggested that the L1 loop region of H2A.Z would sterically clash with the corresponding region of canonical H2A in the heterotypic nucleosome. To resolve this issue, we determined the crystal structures of heterotypic H2A.Z/H2A nucleosomes. In the H2A.Z/H2A nucleosome structure, the H2A.Z L1 loop structure was drastically altered without any structural changes of the canonical H2A L1 loop, thus avoiding the steric clash. Unexpectedly, the heterotypic H2A.Z/H2A nucleosome is more stable than the homotypic H2A.Z nucleosome. These data suggested that the flexible character of the H2A.Z L1 loop plays an essential role in forming the stable heterotypic H2A.Z/H2A nucleosome.
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Affiliation(s)
- Naoki Horikoshi
- Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Yasuhiro Arimura
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hiroyuki Taguchi
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hitoshi Kurumizaka
- Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan Institute for Medical-oriented Structural Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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28
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Machida S, Sekine S, Nishiyama Y, Horikoshi N, Kurumizaka H. Structural and biochemical analyses of monoubiquitinated human histones H2B and H4. Open Biol 2017; 6:rsob.160090. [PMID: 27335322 PMCID: PMC4929944 DOI: 10.1098/rsob.160090] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 05/20/2016] [Indexed: 01/05/2023] Open
Abstract
Monoubiquitination is a major histone post-translational modification. In humans, the histone H2B K120 and histone H4 K31 residues are monoubiquitinated and may form transcriptionally active chromatin. In this study, we reconstituted nucleosomes containing H2B monoubiquitinated at position 120 (H2Bub120) and/or H4 monoubiquitinated at position 31 (H4ub31). We found that the H2Bub120 and H4ub31 monoubiquitinations differently affect nucleosome stability: the H2Bub120 monoubiquitination enhances the H2A–H2B association with the nucleosome, while the H4ub31 monoubiquitination decreases the H3–H4 stability in the nucleosome, when compared with the unmodified nucleosome. The H2Bub120 and H4ub31 monoubiquitinations both antagonize the Mg2+-dependent compaction of a poly-nucleosome, suggesting that these monoubiquitinations maintain more relaxed conformations of chromatin. In the crystal structure, the H2Bub120 and H4ub31 monoubiquitinations do not change the structure of the nucleosome core particle and the ubiquitin molecules were flexibly disordered in the H2Bub120/H4ub31 nucleosome structure. These results revealed the differences and similarities of the H2Bub120 and H4ub31 monoubiquitinations at the mono- and poly-nucleosome levels and provide novel information to clarify the roles of monoubiquitination in chromatin.
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Affiliation(s)
- Shinichi Machida
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Satoshi Sekine
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Yuuki Nishiyama
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Naoki Horikoshi
- Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan Institute for Medical-oriented Structural Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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29
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The Histone Variant H2A.Z Is a Master Regulator of the Epithelial-Mesenchymal Transition. Cell Rep 2017; 21:943-952. [DOI: 10.1016/j.celrep.2017.09.086] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/17/2017] [Accepted: 09/25/2017] [Indexed: 11/20/2022] Open
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30
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Theißen G, Melzer R, Rümpler F. MADS-domain transcription factors and the floral quartet model of flower development: linking plant development and evolution. Development 2017; 143:3259-71. [PMID: 27624831 DOI: 10.1242/dev.134080] [Citation(s) in RCA: 247] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The floral quartet model of floral organ specification poses that different tetramers of MIKC-type MADS-domain transcription factors control gene expression and hence the identity of floral organs during development. Here, we provide a brief history of the floral quartet model and review several lines of recent evidence that support the model. We also describe how the model has been used in contemporary developmental and evolutionary biology to shed light on enigmatic topics such as the origin of land and flowering plants. Finally, we suggest a novel hypothesis describing how floral quartet-like complexes may interact with chromatin during target gene activation and repression.
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Affiliation(s)
- Günter Theißen
- Department of Genetics, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Rainer Melzer
- School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Florian Rümpler
- Department of Genetics, Friedrich Schiller University Jena, 07743 Jena, Germany
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31
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Histone Hypervariants H2A.Z.1 and H2A.Z.2 Play Independent and Context-Specific Roles in Neuronal Activity-Induced Transcription of Arc/Arg3.1 and Other Immediate Early Genes. eNeuro 2017; 4:eN-NWR-0040-17. [PMID: 28856239 PMCID: PMC5569379 DOI: 10.1523/eneuro.0040-17.2017] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 08/07/2017] [Accepted: 08/09/2017] [Indexed: 12/21/2022] Open
Abstract
The histone variant H2A.Z is an essential and conserved regulator of eukaryotic gene transcription. However, the exact role of this histone in the transcriptional process remains perplexing. In vertebrates, H2A.Z has two hypervariants, H2A.Z.1 and H2A.Z.2, that have almost identical sequences except for three amino acid residues. Due to such similarity, functional specificity of these hypervariants in neurobiological processes, if any, remain largely unknown. In this study with dissociated rat cortical neurons, we asked if H2A.Z hypervariants have distinct functions in regulating basal and activity-induced gene transcription. Hypervariant-specific RNAi and microarray analyses revealed that H2A.Z.1 and H2A.Z.2 regulate basal expression of largely nonoverlapping gene sets, including genes that code for several synaptic proteins. In response to neuronal activity, rapid transcription of our model gene Arc is impaired by depletion of H2A.Z.2, but not H2A.Z.1. This impairment is partially rescued by codepletion of the H2A.Z chaperone, ANP32E. In contrast, under a different context (after 48 h of tetrodotoxin, TTX), rapid transcription of Arc is impaired by depletion of either hypervariant. Such context-dependent roles of H2A.Z hypervariants, as revealed by our multiplexed gene expression assays, are also evident with several other immediate early genes, where regulatory roles of these hypervariants vary from gene to gene under different conditions. Together, our data suggest that H2A.Z hypervariants have context-specific roles that complement each other to mediate activity-induced neuronal gene transcription.
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32
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Sasaki S, Matsushita A, Kuroda G, Nakamura HM, Oki Y, Suda T. The Mechanism of Negative Transcriptional Regulation by Thyroid Hormone: Lessons From the Thyrotropin β Subunit Gene. VITAMINS AND HORMONES 2017; 106:97-127. [PMID: 29407449 DOI: 10.1016/bs.vh.2017.06.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Thyroid hormone (T3) activates (positive regulation) or represses (negative regulation) target genes at the transcriptional level. The molecular mechanism of the former has been elucidated in detail; however, the mechanism for negative regulation has not been established. The best example of the gene that is negatively regulated by T3 is the thyrotropin (thyroid-stimulating hormone) β subunit (TSHβ) gene. Analogous to the T3-responsive element (TRE) in positive regulation, a negative TRE (nTRE) has been postulated in the TSHβ gene. However, TSHβ promoter analysis, performed in the presence of transcription factors Pit1 and GATA2, which are determinants of thyrotroph differentiation in the pituitary, revealed that the nTRE is dispensable for inhibition by T3. We propose a tethering model in which the T3 receptor is tethered to GATA2 via protein-protein interaction and inhibits GATA2-dependent transactivation of the TSHβ gene in a T3-dependent manner.
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Affiliation(s)
| | | | - Go Kuroda
- Hamamatsu University School of Medicine, Shizuoka, Japan
| | | | - Yutaka Oki
- Hamamatsu University School of Medicine, Shizuoka, Japan
| | - Takafumi Suda
- Hamamatsu University School of Medicine, Shizuoka, Japan
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33
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The histone H2A isoform Hist2h2ac is a novel regulator of proliferation and epithelial–mesenchymal transition in mammary epithelial and in breast cancer cells. Cancer Lett 2017; 396:42-52. [DOI: 10.1016/j.canlet.2017.03.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 03/01/2017] [Accepted: 03/03/2017] [Indexed: 01/11/2023]
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34
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Taguchi H, Xie Y, Horikoshi N, Maehara K, Harada A, Nogami J, Sato K, Arimura Y, Osakabe A, Kujirai T, Iwasaki T, Semba Y, Tachibana T, Kimura H, Ohkawa Y, Kurumizaka H. Crystal Structure and Characterization of Novel Human Histone H3 Variants, H3.6, H3.7, and H3.8. Biochemistry 2017; 56:2184-2196. [DOI: 10.1021/acs.biochem.6b01098] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hiroyuki Taguchi
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Yan Xie
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Naoki Horikoshi
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Kazumitsu Maehara
- Division of Transcriptomics, Medical
Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi,
Higashi-ku, Fukuoka 812-8582, Japan
| | - Akihito Harada
- Division of Transcriptomics, Medical
Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi,
Higashi-ku, Fukuoka 812-8582, Japan
| | - Jumpei Nogami
- Division of Transcriptomics, Medical
Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi,
Higashi-ku, Fukuoka 812-8582, Japan
| | - Koichi Sato
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Yasuhiro Arimura
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Akihisa Osakabe
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Tomoya Kujirai
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Takeshi Iwasaki
- Division of Transcriptomics, Medical
Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi,
Higashi-ku, Fukuoka 812-8582, Japan
| | - Yuichiro Semba
- Division of Transcriptomics, Medical
Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi,
Higashi-ku, Fukuoka 812-8582, Japan
| | - Taro Tachibana
- Department of Bioengineering, Graduate
School of Engineering, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Hiroshi Kimura
- Cell Biology Unit,
Institute of
Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | - Yasuyuki Ohkawa
- Division of Transcriptomics, Medical
Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi,
Higashi-ku, Fukuoka 812-8582, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural
Biology,
Graduate School of Advanced Science and Engineering, Research Institute
for Science and Engineering, and Institute for Medical-oriented Structural
Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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35
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Soboleva TA, Parker BJ, Nekrasov M, Hart-Smith G, Tay YJ, Tng WQ, Wilkins M, Ryan D, Tremethick DJ. A new link between transcriptional initiation and pre-mRNA splicing: The RNA binding histone variant H2A.B. PLoS Genet 2017; 13:e1006633. [PMID: 28234895 PMCID: PMC5345878 DOI: 10.1371/journal.pgen.1006633] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 03/10/2017] [Accepted: 02/14/2017] [Indexed: 01/08/2023] Open
Abstract
The replacement of histone H2A with its variant forms is critical for regulating all aspects of genome organisation and function. The histone variant H2A.B appeared late in evolution and is most highly expressed in the testis followed by the brain in mammals. This raises the question of what new function(s) H2A.B might impart to chromatin in these important tissues. We have immunoprecipitated the mouse orthologue of H2A.B, H2A.B.3 (H2A.Lap1), from testis chromatin and found this variant to be associated with RNA processing factors and RNA Polymerase (Pol) II. Most interestingly, many of these interactions with H2A.B.3 (Sf3b155, Spt6, DDX39A and RNA Pol II) were inhibited by the presence of endogenous RNA. This histone variant can bind to RNA directly in vitro and in vivo, and associates with mRNA at intron—exon boundaries. This suggests that the ability of H2A.B to bind to RNA negatively regulates its capacity to bind to these factors (Sf3b155, Spt6, DDX39A and RNA Pol II). Unexpectedly, H2A.B.3 forms highly decompacted nuclear subdomains of active chromatin that co-localizes with splicing speckles in male germ cells. H2A.B.3 ChIP-Seq experiments revealed a unique chromatin organization at active genes being not only enriched at the transcription start site (TSS), but also at the beginning of the gene body (but being excluded from the +1 nucleosome) compared to the end of the gene. We also uncover a general histone variant replacement process whereby H2A.B.3 replaces H2A.Z at intron-exon boundaries in the testis and the brain, which positively correlates with expression and exon inclusion. Taken together, we propose that a special mechanism of splicing may occur in the testis and brain whereby H2A.B.3 recruits RNA processing factors from splicing speckles to active genes following its replacement of H2A.Z. The substitution of core histones with their non-allelic variant forms plays a particular important role in regulating chromatin function because they can directly alter the structure of chromatin, and provide new protein interaction interfaces for the recruitment of proteins involved in gene expression. Despite being discovered over a decade ago, the function of H2A.B, a variant of the H2A class, in its proper physiological context (being expressed in the testis and the brain) is unknown. We provide strong evidence that H2A.B has a role in the processing of RNA. It is found in the gene body of an active gene, directly interacts with RNA polymerase II and splicing factors and is located in the nucleus at distinct regions enriched with RNA processing factors (splicing speckles). Most significantly, we show that H2A.B can directly bind to RNA both in vitro and in germ cells. Therefore, H2A.B has the novel ability to bind to both RNA and DNA (as well as proteins) thus directly linking chromatin structure with the function of RNA. Taken together, this suggests that a special mechanism of splicing may operate in the testis and brain.
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Affiliation(s)
- Tatiana A. Soboleva
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Brian J. Parker
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Maxim Nekrasov
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Gene Hart-Smith
- NSW Systems Biology Initiative, University of New South Wales, Sydney, Australia
| | - Ying Jin Tay
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Wei-Quan Tng
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Marc Wilkins
- NSW Systems Biology Initiative, University of New South Wales, Sydney, Australia
| | - Daniel Ryan
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - David J. Tremethick
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
- * E-mail:
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36
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Abstract
The leap from simple unicellularity to complex multicellularity remains one of life's major enigmas. The origins of metazoan developmental gene regulatory mechanisms are sought by analyzing gene regulation in extant eumetazoans, sponges, and unicellular organisms. The main hypothesis of this manuscript is that, developmental enhancers evolved from unicellular inducible promoters that diversified the expression of regulatory genes during metazoan evolution. Promoters and enhancers are functionally similar; both can regulate the transcription of distal promoters and both direct local transcription. Additionally, enhancers have experimentally characterized structural features that reveal their origin from inducible promoters. The distal co-operative regulation among promoters identified in unicellular opisthokonts possibly represents the precursor of distal regulation of promoters by enhancers. During metazoan evolution, constitutive-type promoters of regulatory genes would have acquired novel receptivity to distal regulatory inputs from promoters of inducible genes that eventually specialized as enhancers. The novel regulatory interactions would have caused constitutively expressed genes controlling differential gene expression in unicellular organisms to become themselves differentially expressed. The consequence of the novel regulatory interactions was that regulatory pathways of unicellular organisms became interlaced and ultimately evolved into the intricate developmental gene regulatory networks (GRNs) of extant metazoans.
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Affiliation(s)
- César Arenas-Mena
- Department of Biology, College of Staten Island and Graduate Center, The City University of New York (CUNY), Staten Island, NY 10314, USA
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37
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Zhang K, Xu W, Wang C, Yi X, Zhang W, Su Z. Differential deposition of H2A.Z in combination with histone modifications within related genes in Oryza sativa callus and seedling. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 89:264-277. [PMID: 27643852 DOI: 10.1111/tpj.13381] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 08/14/2016] [Accepted: 09/12/2016] [Indexed: 05/19/2023]
Abstract
As a histone variant, H2A.Z is highly conserved among species and plays a significant role in diverse cellular processes. Here, we generated genome-wide maps of H2A.Z in Oryza sativa (rice) callus and seedling by combining chromatin immunoprecipitation using H2A.Z antibody and high-throughput sequencing. We found a significantly high peak and a small peak of H2A.Z distributed at the 5' and 3' ends of highly expressed genes, respectively. H2A.Z was also associated with inactive genes in both tissues. H3 lysine 4 trimethylation was associated with H2A.Z deposition at the 5' end of expressed genes, and H3 lysine 27 trimethylation peaks were partially associated with H2A.Z. In summary, our study provides global analysis data for the distribution of H2A.Z in the rice genome. Our results demonstrate that the differential deposition of H2A.Z might play important roles in gene transcription during rice development.
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Affiliation(s)
- Kang Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Wenying Xu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Chunchao Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xin Yi
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Wenli Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Collaborative Innovation Center for Modern Crop Production (JCIC-MCP), Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Zhen Su
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
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38
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Kujirai T, Machida S, Osakabe A, Kurumizaka H. Influence of polynucleosome preparation methods on sedimentation velocity analysis of chromatin. J Biochem 2016; 161:381-388. [DOI: 10.1093/jb/mvw081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 11/03/2016] [Indexed: 01/09/2023] Open
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39
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Rudnizky S, Bavly A, Malik O, Pnueli L, Melamed P, Kaplan A. H2A.Z controls the stability and mobility of nucleosomes to regulate expression of the LH genes. Nat Commun 2016; 7:12958. [PMID: 27653784 PMCID: PMC5036153 DOI: 10.1038/ncomms12958] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 08/19/2016] [Indexed: 01/17/2023] Open
Abstract
The structure and dynamics of promoter chromatin have a profound effect on the expression levels of genes. Yet, the contribution of DNA sequence, histone post-translational modifications, histone variant usage and other factors in shaping the architecture of chromatin, and the mechanisms by which this architecture modulates expression of specific genes are not yet completely understood. Here we use optical tweezers to study the roles that DNA sequence and the histone variant H2A.Z have in shaping the chromatin landscape at the promoters of two model genes, Cga and Lhb. Guided by MNase mapping of the promoters of these genes, we reconstitute nucleosomes that mimic those located near the transcriptional start site and immediately downstream (+1), and measure the forces required to disrupt these nucleosomes, and their mobility along the DNA sequence. Our results indicate that these genes are basally regulated by two distinct strategies, making use of H2A.Z to modulate separate phases of transcription, and highlight how DNA sequence, alternative histone variants and remodelling machinery act synergistically to modulate gene expression.
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Affiliation(s)
- Sergei Rudnizky
- Faculty of Biology, Technion—Israel Institute of Technology, Haifa 32000, Israel
| | - Adaiah Bavly
- Faculty of Biology, Technion—Israel Institute of Technology, Haifa 32000, Israel
| | - Omri Malik
- Russell Berrie Nanotechnology Institute, Technion—Israel Institute of Technology, Haifa 32000, Israel
| | - Lilach Pnueli
- Faculty of Biology, Technion—Israel Institute of Technology, Haifa 32000, Israel
| | - Philippa Melamed
- Faculty of Biology, Technion—Israel Institute of Technology, Haifa 32000, Israel
- Russell Berrie Nanotechnology Institute, Technion—Israel Institute of Technology, Haifa 32000, Israel
| | - Ariel Kaplan
- Faculty of Biology, Technion—Israel Institute of Technology, Haifa 32000, Israel
- Russell Berrie Nanotechnology Institute, Technion—Israel Institute of Technology, Haifa 32000, Israel
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Kujirai T, Horikoshi N, Sato K, Maehara K, Machida S, Osakabe A, Kimura H, Ohkawa Y, Kurumizaka H. Structure and function of human histone H3.Y nucleosome. Nucleic Acids Res 2016; 44:6127-41. [PMID: 27016736 PMCID: PMC5291245 DOI: 10.1093/nar/gkw202] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 03/16/2016] [Indexed: 12/25/2022] Open
Abstract
Histone H3.Y is a primate-specific, distant H3 variant. It is evolutionarily derived from H3.3, and may function in transcription regulation. However, the mechanism by which H3.Y regulates transcription has not been elucidated. In the present study, we determined the crystal structure of the H3.Y nucleosome, and found that many H3.Y-specific residues are located on the entry/exit sites of the nucleosome. Biochemical analyses revealed that the DNA ends of the H3.Y nucleosome were more flexible than those of the H3.3 nucleosome, although the H3.Y nucleosome was stable in vitro and in vivo. Interestingly, the linker histone H1, which compacts nucleosomal DNA, appears to bind to the H3.Y nucleosome less efficiently, as compared to the H3.3 nucleosome. These characteristics of the H3.Y nucleosome are also conserved in the H3.Y/H3.3 heterotypic nucleosome, which may be the predominant form in cells. In human cells, H3.Y preferentially accumulated around transcription start sites (TSSs). Taken together, H3.Y-containing nucleosomes around transcription start sites may form relaxed chromatin that allows transcription factor access, to regulate the transcription status of specific genes.
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Affiliation(s)
- Tomoya Kujirai
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Naoki Horikoshi
- Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Koichi Sato
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Kazumitsu Maehara
- Division of Transcriptomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Shinichi Machida
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Akihisa Osakabe
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hiroshi Kimura
- Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan
| | - Yasuyuki Ohkawa
- Division of Transcriptomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan Institute for Medical-oriented Structural Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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41
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Santoro SW, Dulac C. Histone variants and cellular plasticity. Trends Genet 2015; 31:516-27. [PMID: 26299477 PMCID: PMC5111554 DOI: 10.1016/j.tig.2015.07.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 06/15/2015] [Accepted: 07/15/2015] [Indexed: 11/27/2022]
Abstract
The broad diversity of cell types within vertebrates arises from a unique genetic blueprint by combining intrinsic cellular information with developmental and other extrinsic signals. Lying at the interface between cellular signals and the DNA is the chromatin, a dynamic nucleoprotein complex that helps to mediate gene regulation. The most basic subunit of chromatin, the nucleosome, consists of DNA wrapped around histones, a set of proteins that play crucial roles as scaffolding molecules and regulators of gene expression. Growing evidence indicates that canonical histones are commonly replaced by protein variants before and during cellular transitions. We highlight exciting new results suggesting that histone variants are essential players in the control of cellular plasticity during development and in the adult nervous system.
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Affiliation(s)
- Stephen W Santoro
- Neuroscience Program, Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA.
| | - Catherine Dulac
- Howard Hughes Medical Institute, Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
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Abstract
Histone variants are an important part of the histone contribution to chromatin epigenetics. In this review, we describe how the known structural differences of these variants from their canonical histone counterparts impart a chromatin signature ultimately responsible for their epigenetic contribution. In terms of the core histones, H2A histone variants are major players while H3 variant CenH3, with a controversial role in the nucleosome conformation, remains the genuine epigenetic histone variant. Linker histone variants (histone H1 family) haven’t often been studied for their role in epigenetics. However, the micro-heterogeneity of the somatic canonical forms of linker histones appears to play an important role in maintaining the cell-differentiated states, while the cell cycle independent linker histone variants are involved in development. A picture starts to emerge in which histone H2A variants, in addition to their individual specific contributions to the nucleosome structure and dynamics, globally impair the accessibility of linker histones to defined chromatin locations and may have important consequences for determining different states of chromatin metabolism.
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Affiliation(s)
- Manjinder S Cheema
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W-3P6, Canada.
| | - Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W-3P6, Canada.
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43
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Kawashima T, Lorković ZJ, Nishihama R, Ishizaki K, Axelsson E, Yelagandula R, Kohchi T, Berger F. Diversification of histone H2A variants during plant evolution. TRENDS IN PLANT SCIENCE 2015; 20:419-25. [PMID: 25983206 DOI: 10.1016/j.tplants.2015.04.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 04/11/2015] [Accepted: 04/13/2015] [Indexed: 05/19/2023]
Abstract
Among eukaryotes, the four core histones show an extremely high conservation of their structure and form nucleosomes that compact, protect, and regulate access to genetic information. Nevertheless, in multicellular eukaryotes the two families, histone H2A and histone H3, have diversified significantly in key residues. We present a phylogenetic analysis across the green plant lineage that reveals an early diversification of the H2A family in unicellular green algae and remarkable expansions of H2A variants in flowering plants. We define motifs and domains that differentiate plant H2A proteins into distinct variant classes. In non-flowering land plants, we identify a new class of H2A variants and propose their possible role in the emergence of the H2A.W variant class in flowering plants.
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Affiliation(s)
- Tomokazu Kawashima
- Gregor Mendel Institute, Austrian Academy of Sciences, Dr. Bohrgasse 3, 1030 Vienna, Austria
| | - Zdravko J Lorković
- Gregor Mendel Institute, Austrian Academy of Sciences, Dr. Bohrgasse 3, 1030 Vienna, Austria
| | - Ryuichi Nishihama
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | | | - Elin Axelsson
- Gregor Mendel Institute, Austrian Academy of Sciences, Dr. Bohrgasse 3, 1030 Vienna, Austria
| | - Ramesh Yelagandula
- Gregor Mendel Institute, Austrian Academy of Sciences, Dr. Bohrgasse 3, 1030 Vienna, Austria
| | - Takayuki Kohchi
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Frederic Berger
- Gregor Mendel Institute, Austrian Academy of Sciences, Dr. Bohrgasse 3, 1030 Vienna, Austria.
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44
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Jarillo JA, Piñeiro M. H2A.Z mediates different aspects of chromatin function and modulates flowering responses in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 83:96-109. [PMID: 25943140 DOI: 10.1111/tpj.12873] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 04/17/2015] [Accepted: 04/22/2015] [Indexed: 05/23/2023]
Abstract
Eukaryotic organisms have canonical histones and a number of histone variants that perform specialized functions and confer particular structural properties to the nucleosomes that contain them. The histone H2A family comprises several variants, with H2A.Z being the most evolutionarily conserved. This variant is essential in eukaryotes and has emerged as a key player in chromatin function, performing an essential role in gene transcription and genome stability. During recent years, biochemical, genetic and genomic studies have begun to uncover the role of several ATP-dependent chromatin-remodeling complexes in H2A.Z deposition and removal. These ATPase complexes are widely conserved from yeast to mammals. In Arabidopsis there are homologs for most of the subunits of these complexes, and their functions are just beginning to be unveiled. In this review, we discuss the major contributions made in relation to the biology of the H2A.Z in plants, and more specifically concerning the function of this histone variant in the transition from vegetative to reproductive development. Recent advances in the understanding of the molecular mechanisms underlying the H2A.Z-mediated modulation of the floral transition, and thermosensory flowering responses in particular, are discussed. The emerging picture shows that plants contain chromatin-remodeling complexes related to those involved in modulating the dynamics of H2A.Z in other eukaryotes, but their precise biochemical nature remains elusive.
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Affiliation(s)
- José A Jarillo
- Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigaciones Agrarias-Universidad Politécnica de Madrid, 28223, Madrid, Spain
| | - Manuel Piñeiro
- Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigaciones Agrarias-Universidad Politécnica de Madrid, 28223, Madrid, Spain
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45
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Abstract
The multiple lineages and differentiation states that constitute the T-cell compartment all derive from a common thymic precursor. These distinct transcriptional states are maintained both in time and after multiple rounds of cell division by the concerted actions of a small set of lineage-defining transcription factors that act in conjunction with a suite of chromatin-modifying enzymes to activate, repress, and fine-tune gene expression. These chromatin modifications collectively provide an epigenetic code that allows the stable and heritable maintenance of the T-cell phenotype. Recently, it has become apparent that the epigenetic code represents a therapeutic target for a variety of immune cell disorders, including lymphoma and acute and chronic inflammatory diseases. Here, we review the recent advances in epigenetic regulation of gene expression, particularly as it relates to the T-cell differentiation and function.
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Affiliation(s)
- Rhys S Allan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Vic., Australia; Department of Medical Biology, The University of Melbourne, Parkville, Vic., Australia
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46
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Dunn J, McCuaig R, Tu WJ, Hardy K, Rao S. Multi-layered epigenetic mechanisms contribute to transcriptional memory in T lymphocytes. BMC Immunol 2015; 16:27. [PMID: 25943594 PMCID: PMC4422045 DOI: 10.1186/s12865-015-0089-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Accepted: 03/31/2015] [Indexed: 12/24/2022] Open
Abstract
Background Immunological memory is the ability of the immune system to respond more rapidly and effectively to previously encountered pathogens, a key feature of adaptive immunity. The capacity of memory T cells to “remember” previous cellular responses to specific antigens ultimately resides in their unique patterns of gene expression. Following re-exposure to an antigen, previously activated genes are transcribed more rapidly and robustly in memory T cells compared to their naïve counterparts. The ability for cells to remember past transcriptional responses is termed “adaptive transcriptional memory”. Results Recent global epigenome studies suggest that epigenetic mechanisms are central to establishing and maintaining transcriptional memory, with elegant studies in model organisms providing tantalizing insights into the epigenetic programs that contribute to adaptive immunity. These epigenetic mechanisms are diverse, and include not only classical acetylation and methylation events, but also exciting and less well-known mechanisms involving histone structure, upstream signalling pathways, and nuclear localisation of genomic regions. Conclusions Current global health challenges in areas such as tuberculosis and influenza demand not only more effective and safer vaccines, but also vaccines for a wider range of health priorities, including HIV, cancer, and emerging pathogens such as Ebola. Understanding the multi-layered epigenetic mechanisms that underpin the rapid recall responses of memory T cells following reactivation is a critical component of this development pathway.
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Affiliation(s)
- Jennifer Dunn
- Faculty of Education, Science, Technology & Maths, University of Canberra, Canberra, ACT, Australia.
| | - Robert McCuaig
- Faculty of Education, Science, Technology & Maths, University of Canberra, Canberra, ACT, Australia.
| | - Wen Juan Tu
- Faculty of Education, Science, Technology & Maths, University of Canberra, Canberra, ACT, Australia.
| | - Kristine Hardy
- Faculty of Education, Science, Technology & Maths, University of Canberra, Canberra, ACT, Australia.
| | - Sudha Rao
- Faculty of Education, Science, Technology & Maths, University of Canberra, Canberra, ACT, Australia.
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47
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Razin SV, Gavrilov AA, Ulyanov SV. Transcription-controlling regulatory elements of the eukaryotic genome. Mol Biol 2015. [DOI: 10.1134/s0026893315020119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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48
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Shaytan AK, Landsman D, Panchenko AR. Nucleosome adaptability conferred by sequence and structural variations in histone H2A-H2B dimers. Curr Opin Struct Biol 2015; 32:48-57. [PMID: 25731851 DOI: 10.1016/j.sbi.2015.02.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 01/27/2015] [Accepted: 02/06/2015] [Indexed: 12/15/2022]
Abstract
Nucleosome variability is essential for their functions in compacting the chromatin structure and regulation of transcription, replication and cell reprogramming. The DNA molecule in nucleosomes is wrapped around an octamer composed of four types of core histones (H3, H4, H2A, H2B). Nucleosomes represent dynamic entities and may change their conformation, stability and binding properties by employing different sets of histone variants or by becoming post-translationally modified. There are many variants of histones H2A and H2B. Specific H2A and H2B variants may preferentially associate with each other resulting in different combinations of variants and leading to the increased combinatorial complexity of nucleosomes. In addition, the H2A-H2B dimer can be recognized and substituted by chaperones/remodelers as a distinct unit, can assemble independently and is stable during nucleosome unwinding. In this review we discuss how sequence and structural variations in H2A-H2B dimers may provide necessary complexity and confer the nucleosome functional variability.
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Affiliation(s)
- Alexey K Shaytan
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - David Landsman
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Anna R Panchenko
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
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49
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Shah A, Oldenburg A, Collas P. A hyper-dynamic nature of bivalent promoter states underlies coordinated developmental gene expression modules. BMC Genomics 2014; 15:1186. [PMID: 25551786 PMCID: PMC4320513 DOI: 10.1186/1471-2164-15-1186] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 12/15/2014] [Indexed: 02/07/2023] Open
Abstract
Background Chromatin remodeling is crucial for proper programing of developmental gene expression. Recent work provides a dynamic view of post-translational histone modifications during differentiation; however there is little insight on the evolution of combinatorial genome-wide patterns of chromatin marks, excluding an essential aspect of developmental gene regulation. Results We report here a 15-chromatin state Hidden Markov Model which describes changes in chromatin signatures in relation to transcription profiles during differentiation of human pre-adipocytes into adipocytes. We identify nineteen modules of gene expression reflecting multiple waves of transcriptional up- and down-regulation which characterize adipogenic differentiation. From our model, we developed chromatin state matrices fitting each of these transcription modules to show how the complexity and dynamic nature of chromatin signatures relate to expression patterns. Spatial relationships between chromatin states underlie a high-order chromatin organization in differentiating adipocytes. We show the importance of gene expression level in generating diversity in chromatin signatures, and show that the hyper-dynamic nature of H3K4me2/H3K27me3-marked ‘bivalent’ promoter states underlies many of the gene expression patterns associated with adipogenic differentiation. Conclusions Our results reveal the highly dynamic nature of bivalent promoter states within the adipogenic lineage. The data constitute a valuable resource enabling the assessment of possibilities to alter the adipogenic program. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1186) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | - Philippe Collas
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, 0317 Oslo, Norway.
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