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Fan J, Moreno AT, Baier AS, Loparo JJ, Peterson CL. H2A.Z deposition by SWR1C involves multiple ATP-dependent steps. Nat Commun 2022; 13:7052. [PMID: 36396651 PMCID: PMC9672302 DOI: 10.1038/s41467-022-34861-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 11/09/2022] [Indexed: 11/18/2022] Open
Abstract
Histone variant H2A.Z is a conserved feature of nucleosomes flanking protein-coding genes. Deposition of H2A.Z requires ATP-dependent replacement of nucleosomal H2A by a chromatin remodeler related to the multi-subunit enzyme, yeast SWR1C. How these enzymes use ATP to promote this nucleosome editing reaction remains unclear. Here we use single-molecule and ensemble methodologies to identify three ATP-dependent phases in the H2A.Z deposition reaction. Real-time analysis of single nucleosome remodeling events reveals an initial priming step that occurs after ATP addition that involves a combination of both transient DNA unwrapping from the nucleosome and histone octamer deformations. Priming is followed by rapid loss of histone H2A, which is subsequently released from the H2A.Z nucleosomal product. Surprisingly, rates of both priming and the release of the H2A/H2B dimer are sensitive to ATP concentration. This complex reaction pathway provides multiple opportunities to regulate timely and accurate deposition of H2A.Z at key genomic locations.
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Affiliation(s)
- Jiayi Fan
- grid.168645.80000 0001 0742 0364Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605 USA ,grid.168645.80000 0001 0742 0364Interdisciplinary Graduate Program, University of Massachusetts Chan Medical School, Worcester, MA 01605 USA
| | - Andrew T. Moreno
- grid.38142.3c000000041936754XDepartment of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115 USA
| | - Alexander S. Baier
- grid.168645.80000 0001 0742 0364Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605 USA ,grid.168645.80000 0001 0742 0364Medical Scientist Training Program, University of Massachusetts Chan Medical School, Worcester, MA 01605 USA
| | - Joseph J. Loparo
- grid.38142.3c000000041936754XDepartment of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115 USA
| | - Craig L. Peterson
- grid.168645.80000 0001 0742 0364Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605 USA
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2
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Abstract
Mechanical deformations of DNA such as bending are ubiquitous and implicated in diverse cellular functions1. However, the lack of high-throughput tools to directly measure the mechanical properties of DNA limits our understanding of whether and how DNA sequences modulate DNA mechanics and associated chromatin transactions genome-wide. We developed an assay called loop-seq to measure the intrinsic cyclizability of DNA – a proxy for DNA bendability – in high throughput. We measured the intrinsic cyclizabilities of 270,806 50 bp DNA fragments that span the entire length of S. cerevisiae chromosome V and other genomic regions, and also include random sequences. We discovered sequence-encoded regions of unusually low bendability upstream of Transcription Start Sites (TSSs). These regions disfavor the sharp DNA bending required for nucleosome formation and are co-centric with known Nucleosome Depleted Regions (NDRs). We show biochemically that low bendability of linker DNA located about 40 bp away from a nucleosome edge inhibits nucleosome sliding into the linker by the chromatin remodeler INO80. The observation explains how INO80 can create promoter-proximal nucleosomal arrays in the absence of any other factors2 by reading the DNA mechanical landscape. We show that chromosome wide, nucleosomes are characterized by high DNA bendability near dyads and low bendability near the linkers. This contrast increases for nucleosomes deeper into gene bodies, suggesting that DNA mechanics plays a previously unappreciated role in organizing nucleosomes far from the TSS, where nucleosome remodelers predominate. Importantly, random substitution of synonymous codons does not preserve this contrast, suggesting that the evolution of codon choice has been impacted by selective pressure to preserve sequence-encoded mechanical modulations along genes. We also provide evidence that transcription through the TSS-proximal nucleosomes is impacted by local DNA mechanics. Overall, this first genome-scale map of DNA mechanics hints at a ‘mechanical code’ with broad functional implications.
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3
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Singh RK, Fan J, Gioacchini N, Watanabe S, Bilsel O, Peterson CL. Transient Kinetic Analysis of SWR1C-Catalyzed H2A.Z Deposition Unravels the Impact of Nucleosome Dynamics and the Asymmetry of Histone Exchange. Cell Rep 2020; 27:374-386.e4. [PMID: 30970243 PMCID: PMC6545893 DOI: 10.1016/j.celrep.2019.03.035] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 01/20/2019] [Accepted: 03/08/2019] [Indexed: 12/16/2022] Open
Abstract
The SWR1C chromatin remodeling enzyme catalyzes ATP-dependent replacement of nucleosomal H2A with the H2A.Z variant, regulating key DNA-mediated processes such as transcription and DNA repair. Here, we investigate the transient kinetic mechanism of the histone exchange reaction, employing ensemble FRET, fluorescence correlation spectroscopy (FCS), and the steady-state kinetics of ATP hydrolysis. Our studies indicate that SWR1C modulates nucleosome dynamics on both the millisecond and microsecond timescales, poising the nucleosome for the dimer exchange reaction. The transient kinetic analysis of the remodeling reaction performed under single turnover conditions unraveled a striking asymmetry in the ATP-dependent replacement of nucleosomal dimers, promoted by localized DNA unwrapping. Taken together, our transient kinetic studies identify intermediates and provide crucial insights into the SWR1C-catalyzed dimer exchange reaction and shed light on how the mechanics of H2A.Z deposition might contribute to transcriptional regulation in vivo. The SWR1C remodeling enzyme catalyzes ATP-dependent replacement of nucleosomal H2A with the H2A.Z variant at promoter-proximal nucleosomes. Singh et al. investigate the transient kinetic mechanism of this histone exchange reaction and show that SWR1C transiently unwraps nucleosomal DNA, promoting a concerted dimer eviction and replacement reaction.
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Affiliation(s)
- Raushan K Singh
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Jiayl Fan
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Nathan Gioacchini
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Shinya Watanabe
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Osman Bilsel
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Craig L Peterson
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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4
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Wang A, Kolhe JA, Gioacchini N, Baade I, Brieher WM, Peterson CL, Freeman BC. Mechanism of Long-Range Chromosome Motion Triggered by Gene Activation. Dev Cell 2020; 52:309-320.e5. [PMID: 31902656 DOI: 10.1016/j.devcel.2019.12.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 11/18/2019] [Accepted: 12/12/2019] [Indexed: 12/18/2022]
Abstract
Movement of chromosome sites within interphase cells is critical for numerous pathways including RNA transcription and genome organization. Yet, a mechanism for reorganizing chromatin in response to these events had not been reported. Here, we delineate a molecular chaperone-dependent pathway for relocating activated gene loci in yeast. Our presented data support a model in which a two-authentication system mobilizes a gene promoter through a dynamic network of polymeric nuclear actin. Transcription factor-dependent nucleation of a myosin motor propels the gene locus through the actin matrix, and fidelity of the actin association was ensured by ARP-containing chromatin remodelers. Motor activity of nuclear myosin was dependent on the Hsp90 chaperone. Hsp90 further contributed by biasing the remodeler-actin interaction toward nucleosomes with the non-canonical histone H2A.Z, thereby focusing the pathway on select sites such as transcriptionally active genes. Together, the system provides a rapid and effective means to broadly yet selectively mobilize chromatin sites.
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Affiliation(s)
- Anqi Wang
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Janhavi A Kolhe
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Nate Gioacchini
- Program of Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Imke Baade
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - William M Brieher
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Craig L Peterson
- Program of Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Brian C Freeman
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA.
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5
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Rees DM, Willhoft O, Lin CL, Bythell-Douglas R, Wigley DB. Production and Assay of Recombinant Multisubunit Chromatin Remodeling Complexes. Methods Enzymol 2017; 592:27-47. [PMID: 28668124 DOI: 10.1016/bs.mie.2017.03.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
We have developed a novel system to facilitate the rapid and easy cloning of multiple genes (>10) in under a week. Using this system we have been able to successfully clone, overexpress, and purify a number of large multimeric proteins from insect cells, including the chromatin remodeling complexes SWR1 and INO80. Using Förster resonance energy transfer (FRET)-based assays we have demonstrated that our overexpressed enzymes have activities comparable to those purified from sources where the proteins are expressed under their endogenous promoters.
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Affiliation(s)
- David M Rees
- Section of Structural Biology, Imperial College London, London, United Kingdom
| | - Oliver Willhoft
- Section of Structural Biology, Imperial College London, London, United Kingdom
| | - Chia-Liang Lin
- Section of Structural Biology, Imperial College London, London, United Kingdom
| | | | - Dale B Wigley
- Section of Structural Biology, Imperial College London, London, United Kingdom.
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6
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Azmi IF, Watanabe S, Maloney MF, Kang S, Belsky JA, MacAlpine DM, Peterson CL, Bell SP. Nucleosomes influence multiple steps during replication initiation. eLife 2017; 6. [PMID: 28322723 PMCID: PMC5400510 DOI: 10.7554/elife.22512] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 03/20/2017] [Indexed: 12/20/2022] Open
Abstract
Eukaryotic replication origin licensing, activation and timing are influenced by chromatin but a mechanistic understanding is lacking. Using reconstituted nucleosomal DNA replication assays, we assessed the impact of nucleosomes on replication initiation. To generate distinct nucleosomal landscapes, different chromatin-remodeling enzymes (CREs) were used to remodel nucleosomes on origin-DNA templates. Nucleosomal organization influenced two steps of replication initiation: origin licensing and helicase activation. Origin licensing assays showed that local nucleosome positioning enhanced origin specificity and modulated helicase loading by influencing ORC DNA binding. Interestingly, SWI/SNF- and RSC-remodeled nucleosomes were permissive for origin licensing but showed reduced helicase activation. Specific CREs rescued replication of these templates if added prior to helicase activation, indicating a permissive chromatin state must be established during origin licensing to allow efficient origin activation. Our studies show nucleosomes directly modulate origin licensing and activation through distinct mechanisms and provide insights into the regulation of replication initiation by chromatin.
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Affiliation(s)
- Ishara F Azmi
- Department of Biology, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States
| | - Shinya Watanabe
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Michael F Maloney
- Department of Biology, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States
| | - Sukhyun Kang
- Department of Biology, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States.,Center for Genomic Integrity, Institute for Basic Science, Ulsan, South Korea
| | - Jason A Belsky
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, United States.,Program in Computational Biology and Bioinformatics, Duke University, Durham, United States
| | - David M MacAlpine
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, United States
| | - Craig L Peterson
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Stephen P Bell
- Department of Biology, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States
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7
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Bdf1 Bromodomains Are Essential for Meiosis and the Expression of Meiotic-Specific Genes. PLoS Genet 2017; 13:e1006541. [PMID: 28068333 PMCID: PMC5261807 DOI: 10.1371/journal.pgen.1006541] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 01/24/2017] [Accepted: 12/15/2016] [Indexed: 11/19/2022] Open
Abstract
Bromodomain and Extra-terminal motif (BET) proteins play a central role in transcription regulation and chromatin signalling pathways. They are present in unicellular eukaryotes and in this study, the role of the BET protein Bdf1 has been explored in Saccharomyces cerevisiae. Mutation of Bdf1 bromodomains revealed defects on both the formation of spores and the meiotic progression, blocking cells at the exit from prophase, before the first meiotic division. This phenotype is associated with a massive deregulation of the transcription of meiotic genes and Bdf1 bromodomains are required for appropriate expression of the key meiotic transcription factor NDT80 and almost all the Ndt80-inducible genes, including APC complex components. Bdf1 notably accumulates on the promoter of Ndt80 and its recruitment is dependent on Bdf1 bromodomains. In addition, the ectopic expression of NDT80 during meiosis partially bypasses this dependency. Finally, purification of Bdf1 partners identified two independent complexes with Bdf2 or the SWR complex, neither of which was required to complete sporulation. Taken together, our results unveil a new role for Bdf1 –working independently from its predominant protein partners Bdf2 and the SWR1 complex–as a regulator of meiosis-specific genes. Chromatin modifying proteins play a central role in transcription regulation and chromatin signalling. In this study we investigated the functional role of the bromodomains of the chromatin protein Bdf1 during yeast gametogenesis. Our results show that the bromodomains of Bdf1 are essential for meiotic progression and the formation of mature spores. Bdf1 bromodomains are required for the expression of key meiotic genes and the master regulator NDT80. Forced expression of NDT80 can partially rescue the formation of spores when Bdf1 bromodomains are mutated. The results presented here indicate that Bdf1 forms two exclusive complexes, with Bdf2 or with the SWR complex. However, none of these complexes are required for sporulation progression. To conclude, our findings suggest that Bdf1 is a new regulator of the meiotic transcription program and of the expression of the master regulator NDT80.
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8
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Wang F, Ranjan A, Wei D, Wu C. Comment on "A histone acetylation switch regulates H2A.Z deposition by the SWR-C remodeling enzyme". Science 2016; 353:358. [DOI: 10.1126/science.aad5921] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 06/10/2016] [Indexed: 11/02/2022]
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9
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Abstract
Short DNA fragments containing single nucleosomes have been extensively employed as simple model experimental systems for analysis of many intranuclear processes, including binding of proteins to nucleosomes, covalent histone modifications, transcription, DNA repair, and ATP-dependent chromatin remodeling. Here we describe several recently developed procedures for obtaining and analysis of mononucleosomes assembled on 200-350-bp DNA fragments.
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10
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Ehrensberger AH, Franchini DM, East P, George R, Matthews N, Maslen SL, Svejstrup JQ. Retention of the Native Epigenome in Purified Mammalian Chromatin. PLoS One 2015; 10:e0133246. [PMID: 26248330 PMCID: PMC4527833 DOI: 10.1371/journal.pone.0133246] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 06/24/2015] [Indexed: 01/13/2023] Open
Abstract
A protocol is presented for the isolation of native mammalian chromatin as fibers of 25-250 nucleosomes under conditions that preserve the natural epigenetic signature. The material is composed almost exclusively of histones and DNA and conforms to the structure expected by electron microscopy. All sequences probed for were retained, indicating that the material is representative of the majority of the genome. DNA methylation marks and histone marks resembled the patterns observed in vivo. Importantly, nucleosome positions also remained largely unchanged, except on CpG islands, where nucleosomes were found to be unstable. The technical challenges of reconstituting biochemical reactions with native mammalian chromatin are discussed.
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Affiliation(s)
- Andreas H. Ehrensberger
- Mechanisms of Transcription Laboratory, Clare Hall Laboratories, The Francis Crick Insitute, London Research Institute, South Mimms, United Kingdom
| | - Don-Marc Franchini
- DNA Editing Lab, Clare Hall Laboratories, Cancer Research UK, London Research Institute, South Mimms, United Kingdom
- DNA Editing in Immunity and Epigenetics, IFOM-Fondazione Instituto FIRC di Oncologia Molecolare, Milano, Italy
| | - Philip East
- Bioinformatics and Biostatistics Group, The Francis Crick Insitute, London Research Institute, London, United Kingdom
| | - Roger George
- Protein Purification Facility, The Francis Crick Insitute, London Research Institute, London, United Kingdom
| | - Nik Matthews
- Advanced Sequencing Facility, The Francis Crick Insitute, London Research Institute, London, United Kingdom
| | - Sarah L. Maslen
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Jesper Q. Svejstrup
- Mechanisms of Transcription Laboratory, Clare Hall Laboratories, The Francis Crick Insitute, London Research Institute, South Mimms, United Kingdom
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11
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Kudryashova KS, Chertkov OV, Nikitin DV, Pestov NA, Kulaeva OI, Efremenko AV, Solonin AS, Kirpichnikov MP, Studitsky VM, Feofanov AV. Preparation of mononucleosomal templates for analysis of transcription with RNA polymerase using spFRET. Methods Mol Biol 2015; 1288:395-412. [PMID: 25827893 DOI: 10.1007/978-1-4939-2474-5_23] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Single positioned nucleosomes have been extensively employed as simple model experimental systems for analysis of various intranuclear processes. Here we describe an experimental system containing positioned mononucleosomes allowing transcription by various RNA polymerases. Each DNA template contains a pair of fluorescent labels (Cy3 and Cy5) allowing measuring relative distances between the neighboring coils of nucleosomal DNA using Forster resonance energy transfer (FRET). The single-particle FRET (spFRET) approach for analysis of DNA uncoiling from the histone octamer during transcription through chromatin is described in detail.
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Affiliation(s)
- Kseniya S Kudryashova
- Biology Faculty, Lomonosov, Moscow State University, Leninskie Gory 1, Moscow, 119992, Russia
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12
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Ranjan A, Mizuguchi G, FitzGerald PC, Wei D, Wang F, Huang Y, Luk E, Woodcock CL, Wu C. Nucleosome-free region dominates histone acetylation in targeting SWR1 to promoters for H2A.Z replacement. Cell 2013; 154:1232-45. [PMID: 24034247 DOI: 10.1016/j.cell.2013.08.005] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 06/04/2013] [Accepted: 08/05/2013] [Indexed: 01/31/2023]
Abstract
The histone variant H2A.Z is a genome-wide signature of nucleosomes proximal to eukaryotic regulatory DNA. Whereas the multisubunit chromatin remodeler SWR1 is known to catalyze ATP-dependent deposition of H2A.Z, the mechanism of SWR1 recruitment to S. cerevisiae promoters has been unclear. A sensitive assay for competitive binding of dinucleosome substrates revealed that SWR1 preferentially binds long nucleosome-free DNA and the adjoining nucleosome core particle, allowing discrimination of gene promoters over gene bodies. Analysis of mutants indicates that the conserved Swc2/YL1 subunit and the adenosine triphosphatase domain of Swr1 are mainly responsible for binding to substrate. SWR1 binding is enhanced on nucleosomes acetylated by the NuA4 histone acetyltransferase, but recognition of nucleosome-free and nucleosomal DNA is dominant over interaction with acetylated histones. Such hierarchical cooperation between DNA and histone signals expands the dynamic range of genetic switches, unifying classical gene regulation by DNA-binding factors with ATP-dependent nucleosome remodeling and posttranslational histone modifications.
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Affiliation(s)
- Anand Ranjan
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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13
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Byeon B, Wang W, Barski A, Ranallo RT, Bao K, Schones DE, Zhao K, Wu C, Wu WH. The ATP-dependent chromatin remodeling enzyme Fun30 represses transcription by sliding promoter-proximal nucleosomes. J Biol Chem 2013; 288:23182-93. [PMID: 23779104 DOI: 10.1074/jbc.m113.471979] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The evolutionarily conserved ATP-dependent chromatin remodeling enzyme Fun30 has recently been shown to play important roles in heterochromatin silencing and DNA repair. However, how Fun30 remodels nucleosomes is not clear. Here we report a nucleosome sliding activity of Fun30 and its role in transcriptional repression. We observed that Fun30 repressed the expression of genes involved in amino acid and carbohydrate metabolism, the stress response, and meiosis. In addition, Fun30 was localized at the 5' and 3' ends of genes and within the open reading frames of its targets. Consistent with its role in gene repression, we observed that Fun30 target genes lacked histone modifications often associated with gene activation and showed an increased level of ubiquitinated histone H2B. Furthermore, a genome-wide nucleosome mapping analysis revealed that the length of the nucleosome-free region at the 5' end of a subset of genes was changed in Fun30-depleted cells. In addition, the positions of the -1, +2, and +3 nucleosomes at the 5' end of target genes were shifted significantly, whereas the position of the +1 nucleosome remained largely unchanged in the fun30Δ mutant. Finally, we demonstrated that affinity-purified, single-component Fun30 exhibited a nucleosome sliding activity in an ATP-dependent manner. These results define a role for Fun30 in the regulation of transcription and indicate that Fun30 remodels chromatin at the 5' end of genes by sliding promoter-proximal nucleosomes.
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Affiliation(s)
- Boseon Byeon
- Institute of Molecular Medicine and Genetics, Department of Neurology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia 30912, USA
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