1
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Singh S, Anderson N, Chu D, Roy SW. Nematode histone H2A variant evolution reveals diverse histories of retention and loss and evidence for conserved core-like variant histone genes. PLoS One 2024; 19:e0300190. [PMID: 38814971 PMCID: PMC11139335 DOI: 10.1371/journal.pone.0300190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 02/22/2024] [Indexed: 06/01/2024] Open
Abstract
Histone variants are paralogs that replace canonical histones in nucleosomes, often imparting novel functions. However, how histone variants arise and evolve is poorly understood. Reconstruction of histone protein evolution is challenging due to large differences in evolutionary rates across gene lineages and sites. Here we used intron position data from 108 nematode genomes in combination with amino acid sequence data to find disparate evolutionary histories of the three H2A variants found in Caenorhabditis elegans: the ancient H2A.ZHTZ-1, the sperm-specific HTAS-1, and HIS-35, which differs from the canonical S-phase H2A by a single glycine-to-alanine C-terminal change. Although the H2A.ZHTZ-1 protein sequence is highly conserved, its gene exhibits recurrent intron gain and loss. This pattern suggests that specific intron sequences or positions may not be important to H2A.Z functionality. For HTAS-1 and HIS-35, we find variant-specific intron positions that are conserved across species. Patterns of intron position conservation indicate that the sperm-specific variant HTAS-1 arose more recently in the ancestor of a subset of Caenorhabditis species, while HIS-35 arose in the ancestor of Caenorhabditis and its sister group, including the genus Diploscapter. HIS-35 exhibits gene retention in some descendent lineages but gene loss in others, suggesting that histone variant use or functionality can be highly flexible. Surprisingly, we find the single amino acid differentiating HIS-35 from core H2A is ancestral and common across canonical Caenorhabditis H2A sequences. Thus, we speculate that the role of HIS-35 lies not in encoding a functionally distinct protein, but instead in enabling H2A expression across the cell cycle or in distinct tissues. This work illustrates how genes encoding such partially-redundant functions may be advantageous yet relatively replaceable over evolutionary timescales, consistent with the patchwork pattern of retention and loss of both genes. Our study shows the utility of intron positions for reconstructing evolutionary histories of gene families, particularly those undergoing idiosyncratic sequence evolution.
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Affiliation(s)
- Swadha Singh
- Quantitative & Systems Biology, University of California, Merced, Merced, California, United States of America
| | - Noelle Anderson
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Diana Chu
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Scott W. Roy
- Quantitative & Systems Biology, University of California, Merced, Merced, California, United States of America
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
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2
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Karam G, Molaro A. Casting histone variants during mammalian reproduction. Chromosoma 2023:10.1007/s00412-023-00803-9. [PMID: 37347315 PMCID: PMC10356639 DOI: 10.1007/s00412-023-00803-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/31/2023] [Accepted: 06/05/2023] [Indexed: 06/23/2023]
Abstract
During mammalian reproduction, germ cell chromatin packaging is key to prepare parental genomes for fertilization and to initiate embryonic development. While chromatin modifications such as DNA methylation and histone post-translational modifications are well known to carry regulatory information, histone variants have received less attention in this context. Histone variants alter the stability, structure and function of nucleosomes and, as such, contribute to chromatin organization in germ cells. Here, we review histone variants expression dynamics during the production of male and female germ cells, and what is currently known about their parent-of-origin effects during reproduction. Finally, we discuss the apparent conundrum behind these important functions and their recent evolutionary diversification.
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Affiliation(s)
- Germaine Karam
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, INSERM U1103, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Antoine Molaro
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, INSERM U1103, Université Clermont Auvergne, Clermont-Ferrand, France.
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3
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Seal RL, Denny P, Bruford EA, Gribkova AK, Landsman D, Marzluff WF, McAndrews M, Panchenko AR, Shaytan AK, Talbert PB. A standardized nomenclature for mammalian histone genes. Epigenetics Chromatin 2022; 15:34. [PMID: 36180920 PMCID: PMC9526256 DOI: 10.1186/s13072-022-00467-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/21/2022] [Indexed: 11/10/2022] Open
Abstract
Histones have a long history of research in a wide range of species, leaving a legacy of complex nomenclature in the literature. Community-led discussions at the EMBO Workshop on Histone Variants in 2011 resulted in agreement amongst experts on a revised systematic protein nomenclature for histones, which is based on a combination of phylogenetic classification and historical symbol usage. Human and mouse histone gene symbols previously followed a genome-centric system that was not applicable across all vertebrate species and did not reflect the systematic histone protein nomenclature. This prompted a collaboration between histone experts, the Human Genome Organization (HUGO) Gene Nomenclature Committee (HGNC) and Mouse Genomic Nomenclature Committee (MGNC) to revise human and mouse histone gene nomenclature aiming, where possible, to follow the new protein nomenclature whilst conforming to the guidelines for vertebrate gene naming. The updated nomenclature has also been applied to orthologous histone genes in chimpanzee, rhesus macaque, dog, cat, pig, horse and cattle, and can serve as a framework for naming other vertebrate histone genes in the future.
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Affiliation(s)
- Ruth L Seal
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, CB10 1SD, UK.
- Department of Haematology, School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0PT, UK.
| | - Paul Denny
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, CB10 1SD, UK
| | - Elspeth A Bruford
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, CB10 1SD, UK
- Department of Haematology, School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0PT, UK
| | - Anna K Gribkova
- Department of Biology, Lomonosov Moscow State University, 119234, Moscow, Russia
| | - David Landsman
- Intramural Research Program, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20892, USA
| | - William F Marzluff
- Integrated Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Monica McAndrews
- Mouse Genome Informatics, The Jackson Laboratory, 600 Main Street, Bar Harbor, ME, 04609, USA
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Alexey K Shaytan
- Department of Biology, Lomonosov Moscow State University, 119234, Moscow, Russia
| | - Paul B Talbert
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, Seattle, WA, 98109, USA
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4
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Osakabe A, Molaro A. Histone renegades: Unusual H2A histone variants in plants and animals. Semin Cell Dev Biol 2022; 135:35-42. [PMID: 35570098 DOI: 10.1016/j.semcdb.2022.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 04/19/2022] [Accepted: 05/04/2022] [Indexed: 12/27/2022]
Abstract
H2A variants are histones that carry out specialized nucleosome function during the eukaryote genome packaging. Most genes encoding H2A histone variants arose in the distant past, and have highly conserved domains and structures. Yet, novel H2A variants have continued to arise throughout the radiation of eukaryotes and disturbed the apparent tranquility of nucleosomes. These species-specific H2A variants contributed to the functional diversification of nucleosomes through changes in both their structure and expression patterns. In this short review, we discuss the evolutionary trajectories of these histone renegades in plants and animal genomes.
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Affiliation(s)
- Akihisa Osakabe
- Laboratory of Genetics, Department of Biological Sciences, The University of Tokyo, Tokyo, Japan; Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Saitama 332-0012, Japan.
| | - Antoine Molaro
- Genetics, Reproduction & Development Institute (iGReD), CNRS UMR 6293, INSERM U1103, Université Clermont Auvergne, Clermont-Ferrand, France.
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5
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Jiang X, Wen J, Paver E, Wu YH, Sun G, Bullman A, Dahlstrom JE, 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 DOI: 10.15252/embr.202152462] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [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 Research, The Australian National University, Canberra, ACT, Australia
| | - Jiayu Wen
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Elizabeth Paver
- Department of Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Yu-Huan Wu
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Gege Sun
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Amanda Bullman
- Department of Anatomical Pathology, ACT Pathology, The Canberra Hospital, Canberra, ACT, Australia
| | - Jane E Dahlstrom
- Department of Anatomical Pathology, ACT Pathology, The Canberra Hospital, Canberra, ACT, Australia.,Australian National University Medical School, The Australian National University, Canberra, ACT, Australia
| | - David J Tremethick
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Tatiana A Soboleva
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
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6
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DNA methylation and histone variants in aging and cancer. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2021; 364:1-110. [PMID: 34507780 DOI: 10.1016/bs.ircmb.2021.06.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Aging-related diseases such as cancer can be traced to the accumulation of molecular disorder including increased DNA mutations and epigenetic drift. We provide a comprehensive review of recent results in mice and humans on modifications of DNA methylation and histone variants during aging and in cancer. Accumulated errors in DNA methylation maintenance lead to global decreases in DNA methylation with relaxed repression of repeated DNA and focal hypermethylation blocking the expression of tumor suppressor genes. Epigenetic clocks based on quantifying levels of DNA methylation at specific genomic sites is proving to be a valuable metric for estimating the biological age of individuals. Histone variants have specialized functions in transcriptional regulation and genome stability. Their concentration tends to increase in aged post-mitotic chromatin, but their effects in cancer are mainly determined by their specialized functions. Our increased understanding of epigenetic regulation and their modifications during aging has motivated interventions to delay or reverse epigenetic modifications using the epigenetic clocks as a rapid readout for efficacity. Similarly, the knowledge of epigenetic modifications in cancer is suggesting new approaches to target these modifications for cancer therapy.
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7
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Werner A, Clark JE, Samaranayake C, Casement J, Zinad HS, Sadeq S, Al-Hashimi S, Smith M, Kotaja N, Mattick JS. Widespread formation of double-stranded RNAs in testis. Genome Res 2021; 31:1174-1186. [PMID: 34158368 PMCID: PMC8256860 DOI: 10.1101/gr.265603.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 06/02/2021] [Indexed: 12/27/2022]
Abstract
The testis transcriptome is highly complex and includes RNAs that potentially hybridize to form double-stranded RNA (dsRNA). We isolated dsRNA using the monoclonal J2 antibody and deep-sequenced the enriched samples from testes of juvenile Dicer1 knockout mice, age-matched controls, and adult animals. Comparison of our data set with recently published data from mouse liver revealed that the dsRNA transcriptome in testis is markedly different from liver: In testis, dsRNA-forming transcripts derive from mRNAs including promoters and immediate downstream regions, whereas in somatic cells they originate more often from introns and intergenic transcription. The genes that generate dsRNA are significantly expressed in isolated male germ cells with particular enrichment in pachytene spermatocytes. dsRNA formation is lower on the sex (X and Y) chromosomes. The dsRNA transcriptome is significantly less complex in juvenile mice as compared to adult controls and, possibly as a consequence, the knockout of Dicer1 has only a minor effect on the total number of transcript peaks associated with dsRNA. The comparison between dsRNA-associated genes in testis and liver with a reported set of genes that produce endogenous siRNAs reveals a significant overlap in testis but not in liver. Testis dsRNAs also significantly associate with natural antisense genes-again, this feature is not observed in liver. These findings point to a testis-specific mechanism involving natural antisense transcripts and the formation of dsRNAs that feed into the RNA interference pathway, possibly to mitigate the mutagenic impacts of recombination and transposon mobilization.
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Affiliation(s)
- Andreas Werner
- Biosciences Institute, Medical School, Newcastle University, Newcastle, NE2 4HH, United Kingdom
| | - James E Clark
- Biosciences Institute, Medical School, Newcastle University, Newcastle, NE2 4HH, United Kingdom
| | - Calum Samaranayake
- Biosciences Institute, Medical School, Newcastle University, Newcastle, NE2 4HH, United Kingdom
| | - John Casement
- Bioinformatics Support Unit, Medical School, Newcastle University, Newcastle, NE2 4HH, United Kingdom
| | - Hany S Zinad
- Biosciences Institute, Medical School, Newcastle University, Newcastle, NE2 4HH, United Kingdom
| | - Shaymaa Sadeq
- Biosciences Institute, Medical School, Newcastle University, Newcastle, NE2 4HH, United Kingdom
- Fallujah College of Medicine, Al-Fallujah University, Al-Fallujah, 9Q4V+H3, Iraq
| | - Surar Al-Hashimi
- Biosciences Institute, Medical School, Newcastle University, Newcastle, NE2 4HH, United Kingdom
| | - Martin Smith
- CHU Sainte-Justine Research Centre, Montreal, QC H3T 1C5, Canada
- Department of Biochemistry and Molecular Medicine, Faculty of Medicine, University of Montreal, Montreal, QC H3T 1C5, Canada
| | - Noora Kotaja
- Institute of Biomedicine, University of Turku, Turku, FIN-20520, Finland
| | - John S Mattick
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia
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8
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Peng Y, Li S, Landsman D, Panchenko AR. Histone tails as signaling antennas of chromatin. Curr Opin Struct Biol 2021; 67:153-160. [PMID: 33279866 PMCID: PMC8096652 DOI: 10.1016/j.sbi.2020.10.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 10/07/2020] [Accepted: 10/18/2020] [Indexed: 12/19/2022]
Abstract
Histone tails, representing the N-terminal or C-terminal regions flanking the histone core, play essential roles in chromatin signaling networks. Intrinsic disorder of histone tails and their propensity for post-translational modifications allow them to serve as hubs in coordination of epigenetic processes within the nucleosomal context. Deposition of histone variants with distinct histone tail properties further enriches histone tails' repertoire in epigenetic signaling. Given the advances in experimental techniques and in silico modelling, we review the most recent data on histone tails' effects on nucleosome stability and dynamics, their function in regulating chromatin accessibility and folding. Finally, we discuss different molecular mechanisms to understand how histone tails are involved in nucleosome recognition by binding partners and formation of higher-order chromatin structures.
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Affiliation(s)
- Yunhui Peng
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD, USA
| | - Shuxiang Li
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, ON, Canada
| | - David Landsman
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD, USA
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, ON, Canada.
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9
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Espiritu D, Gribkova AK, Gupta S, Shaytan AK, Panchenko AR. Molecular Mechanisms of Oncogenesis through the Lens of Nucleosomes and Histones. J Phys Chem B 2021; 125:3963-3976. [PMID: 33769808 DOI: 10.1021/acs.jpcb.1c00694] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
At the cellular level, cancer is the disease of both the genome and the epigenome, and the interplay between genetic mutations and epigenetic states may occur at the level of elementary chromatin units, the nucleosomes. They are formed by a segment of DNA wrapped around an octamer of histone proteins. In this review, we survey various mechanisms of cancer etiology and progression mediated by histones and nucleosomes. In particular, we discuss the effects of mutations in histones, changes in their expression and slicing on epigenetic dysregulation and carcinogenesis. The links between cancer phenotypes and differential expression of histone variants and isoforms are summarized. Finally, we discourse the geometric and steric effects of DNA compaction in nucleosomes on DNA mutation rate, interactions with transcription factors, including pioneer transcription factors, and prospects of cancer cells' genome and epigenome editing.
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Affiliation(s)
- Daniel Espiritu
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Anna K Gribkova
- Department of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, Moscow, 119991, Russia.,Sirius University of Science and Technology, 1 Olympic Avenue, Sochi, 354340, Russia
| | - Shubhangi Gupta
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Alexey K Shaytan
- Department of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, Moscow, 119991, Russia.,Sirius University of Science and Technology, 1 Olympic Avenue, Sochi, 354340, Russia.,Bioinformatics Lab, Faculty of Computer Science, HSE University, 11 Pokrovsky Boulevard, Moscow, 109028, Russia
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, Ontario, Canada.,Ontario Institute of Cancer Research, Toronto, Ontario, Canada
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10
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Kohestani H, Wereszczynski J. Effects of H2A.B incorporation on nucleosome structures and dynamics. Biophys J 2021; 120:1498-1509. [PMID: 33609493 DOI: 10.1016/j.bpj.2021.01.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/31/2020] [Accepted: 01/12/2021] [Indexed: 01/20/2023] Open
Abstract
The H2A.B histone variant is an epigenetic regulator involved in transcriptional upregulation, DNA synthesis, and splicing that functions by replacing the canonical H2A histone in the nucleosome core particle. Introduction of H2A.B results in less compact nucleosome states with increased DNA unwinding and accessibility at the nucleosomal entry and exit sites. Despite being well characterized experimentally, the molecular mechanisms by which H2A.B incorporation alters nucleosome stability and dynamics remain poorly understood. To study the molecular mechanisms of H2A.B, we have performed a series of conventional and enhanced sampling molecular dynamics simulation of H2A.B- and canonical H2A-containing nucleosomes. Results of conventional simulations show that H2A.B weakens protein-protein and protein-DNA interactions at specific locations throughout the nucleosome. These weakened interactions result in significantly more DNA opening from both the entry and exit sites in enhanced sampling simulations. Furthermore, free energy profiles show that H2A.B-containing nucleosomes have significantly broader free wells and that H2A.B allows for sampling of states with increased DNA breathing, which are shown to be stable on the hundreds of nanoseconds timescale with further conventional simulations. Together, our results show the molecular mechanisms by which H2A.B creates less compacted nucleosome states as a means of increasing genetic accessibility and gene transcription.
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Affiliation(s)
- Havva Kohestani
- Department of Biology, Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, Illinois
| | - Jeff Wereszczynski
- Department of Physics, Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, Illinois.
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11
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Chew GL, Bleakley M, Bradley RK, Malik HS, Henikoff S, Molaro A, Sarthy J. Short H2A histone variants are expressed in cancer. Nat Commun 2021; 12:490. [PMID: 33473122 PMCID: PMC7817690 DOI: 10.1038/s41467-020-20707-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/09/2020] [Indexed: 12/23/2022] Open
Abstract
Short H2A (sH2A) histone variants are primarily expressed in the testes of placental mammals. Their incorporation into chromatin is associated with nucleosome destabilization and modulation of alternate splicing. Here, we show that sH2As innately possess features similar to recurrent oncohistone mutations associated with nucleosome instability. Through analyses of existing cancer genomics datasets, we find aberrant sH2A upregulation in a broad array of cancers, which manifest splicing patterns consistent with global nucleosome destabilization. We posit that short H2As are a class of "ready-made" oncohistones, whose inappropriate expression contributes to chromatin dysfunction in cancer.
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Affiliation(s)
- Guo-Liang Chew
- The Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Marie Bleakley
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Robert K Bradley
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Harmit S Malik
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Steven Henikoff
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Antoine Molaro
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
- Genetics, Reproduction and Development (GReD) Institute, Université Clermont Auvergne, Clermont-Ferrand, France.
| | - Jay Sarthy
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
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12
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Kurumizaka H, Kujirai T, Takizawa Y. Contributions of Histone Variants in Nucleosome Structure and Function. J Mol Biol 2020; 433:166678. [PMID: 33065110 DOI: 10.1016/j.jmb.2020.10.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 11/19/2022]
Abstract
Chromatin compacts genomic DNA in eukaryotes. The primary chromatin unit is the nucleosome core particle, composed of four pairs of the core histones, H2A, H2B, H3, and H4, and 145-147 base pairs of DNA. Since replication, recombination, repair, and transcription take place in chromatin, the structure and dynamics of the nucleosome must be versatile. These nucleosome characteristics underlie the epigenetic regulation of genomic DNA. In higher eukaryotes, many histone variants have been identified as non-allelic isoforms, which confer nucleosome diversity. In this article, we review the manifold types of nucleosomes produced by histone variants, which play important roles in the epigenetic regulation of chromatin.
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Affiliation(s)
- Hitoshi Kurumizaka
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
| | - Tomoya Kujirai
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Yoshimasa Takizawa
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
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13
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Martire S, Banaszynski LA. The roles of histone variants in fine-tuning chromatin organization and function. Nat Rev Mol Cell Biol 2020; 21:522-541. [PMID: 32665685 PMCID: PMC8245300 DOI: 10.1038/s41580-020-0262-8] [Citation(s) in RCA: 187] [Impact Index Per Article: 46.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2020] [Indexed: 12/15/2022]
Abstract
Histones serve to both package and organize DNA within the nucleus. In addition to histone post-translational modification and chromatin remodelling complexes, histone variants contribute to the complexity of epigenetic regulation of the genome. Histone variants are characterized by a distinct protein sequence and a selection of designated chaperone systems and chromatin remodelling complexes that regulate their localization in the genome. In addition, histone variants can be enriched with specific post-translational modifications, which in turn can provide a scaffold for recruitment of variant-specific interacting proteins to chromatin. Thus, through these properties, histone variants have the capacity to endow specific regions of chromatin with unique character and function in a regulated manner. In this Review, we provide an overview of recent advances in our understanding of the contribution of histone variants to chromatin function in mammalian systems. First, we discuss new molecular insights into chaperone-mediated histone variant deposition. Next, we discuss mechanisms by which histone variants influence chromatin properties such as nucleosome stability and the local chromatin environment both through histone variant sequence-specific effects and through their role in recruiting different chromatin-associated complexes. Finally, we focus on histone variant function in the context of both embryonic development and human disease, specifically developmental syndromes and cancer.
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Affiliation(s)
- Sara Martire
- Green Center for Reproductive Biology Sciences, Department of Obstetrics and Gynecology, Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Laura A Banaszynski
- Green Center for Reproductive Biology Sciences, Department of Obstetrics and Gynecology, Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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