1
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Xi S, Nguyen T, Murray S, Lorenz P, Mellor J. Size fractionated NET-Seq reveals a conserved architecture of transcription units around yeast genes. Yeast 2024; 41:222-241. [PMID: 38433440 DOI: 10.1002/yea.3931] [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: 10/30/2023] [Revised: 02/06/2024] [Accepted: 02/09/2024] [Indexed: 03/05/2024] Open
Abstract
Genomes from yeast to humans are subject to pervasive transcription. A single round of pervasive transcription is sufficient to alter local chromatin conformation, nucleosome dynamics and gene expression, but is hard to distinguish from background signals. Size fractionated native elongating transcript sequencing (sfNET-Seq) was developed to precisely map nascent transcripts independent of expression levels. RNAPII-associated nascent transcripts are fractionation into different size ranges before library construction. When anchored to the transcription start sites (TSS) of annotated genes, the combined pattern of the output metagenes gives the expected reference pattern. Bioinformatic pattern matching to the reference pattern identified 9542 transcription units in Saccharomyces cerevisiae, of which 47% are coding and 53% are noncoding. In total, 3113 (33%) are unannotated noncoding transcription units. Anchoring all transcription units to the TSS or polyadenylation site (PAS) of annotated genes reveals distinctive architectures of linked pairs of divergent transcripts approximately 200nt apart. The Reb1 transcription factor is enriched 30nt downstream of the PAS only when an upstream (TSS -60nt with respect to PAS) noncoding transcription unit co-occurs with a downstream (TSS +150nt) coding transcription unit and acts to limit levels of upstream antisense transcripts. The potential for extensive transcriptional interference is evident from low abundance unannotated transcription units with variable TSS (median -240nt) initiating within a 500nt window upstream of, and transcribing over, the promoters of protein-coding genes. This study confirms a highly interleaved yeast genome with different types of transcription units altering the chromatin landscape in distinctive ways, with the potential to exert extensive regulatory control.
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Affiliation(s)
- Shidong Xi
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Tania Nguyen
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Struan Murray
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Phil Lorenz
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Jane Mellor
- Department of Biochemistry, University of Oxford, Oxford, UK
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2
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Cuevas-Bermúdez A, Martínez-Fernández V, Garrido-Godino AI, Jordán-Pla A, Peñate X, Martín-Expósito M, Gutiérrez G, Govind CK, Chávez S, Pelechano V, Navarro F. The association of the RSC remodeler complex with chromatin is influenced by the prefoldin-like Bud27 and determines nucleosome positioning and polyadenylation sites usage in Saccharomyces cerevisiae. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:194995. [PMID: 37967810 DOI: 10.1016/j.bbagrm.2023.194995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/01/2023] [Accepted: 11/06/2023] [Indexed: 11/17/2023]
Abstract
The tripartite interaction between the chromatin remodeler complex RSC, RNA polymerase subunit Rpb5 and prefoldin-like Bud27 is necessary for proper RNA pol II elongation. Indeed lack of Bud27 alters this association and affects transcription elongation. This work investigates the consequences of lack of Bud27 on the chromatin association of RSC and RNA pol II, and on nucleosome positioning. Our results demonstrate that RSC binds chromatin in gene bodies and lack of Bud27 alters this association, mainly around polyA sites. This alteration impacts chromatin organization and leads to the accumulation of RNA pol II molecules around polyA sites, likely due to pausing or arrest. Our data suggest that RSC is necessary to maintain chromatin organization around those sites, and any alteration of this organization results in the widespread use of alternative polyA sites. Finally, we also find a similar molecular phenotype that occurs upon TOR inhibition with rapamycin, which suggests that alternative polyadenylation observed upon TOR inhibition is likely Bud27-dependent.
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Affiliation(s)
- Abel Cuevas-Bermúdez
- Departamento de Biología Experimental-Genética, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071, Jaén, Spain
| | - Verónica Martínez-Fernández
- Departamento de Biología Experimental-Genética, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071, Jaén, Spain
| | - Ana I Garrido-Godino
- Departamento de Biología Experimental-Genética, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071, Jaén, Spain
| | - Antonio Jordán-Pla
- Instituto Biotecmed, Facultad de Biológicas, Universitat de València, E-46100 Burjassot, Valencia, Spain
| | - Xenia Peñate
- Departamento de Genética, Universidad de Sevilla, Seville, Spain; Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville, Spain
| | - Manuel Martín-Expósito
- Departamento de Biología Experimental-Genética, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071, Jaén, Spain
| | | | - Chhabi K Govind
- Department of Biological Sciences, Oakland University, Rochester, MI 48309, USA
| | - Sebastián Chávez
- Departamento de Genética, Universidad de Sevilla, Seville, Spain; Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville, Spain
| | - Vicent Pelechano
- SciLifeLab, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 65 Solna, Sweden
| | - Francisco Navarro
- Departamento de Biología Experimental-Genética, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071, Jaén, Spain; Instituto Universitario de Investigación en Olivar y Aceites de Oliva, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071, Jaén, Spain.
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3
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Kujirai T, Ehara H, Sekine SI, Kurumizaka H. Structural Transition of the Nucleosome during Transcription Elongation. Cells 2023; 12:1388. [PMID: 37408222 DOI: 10.3390/cells12101388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/10/2023] [Accepted: 05/11/2023] [Indexed: 07/07/2023] Open
Abstract
In eukaryotes, genomic DNA is tightly wrapped in chromatin. The nucleosome is a basic unit of chromatin, but acts as a barrier to transcription. To overcome this impediment, the RNA polymerase II elongation complex disassembles the nucleosome during transcription elongation. After the RNA polymerase II passage, the nucleosome is rebuilt by transcription-coupled nucleosome reassembly. Nucleosome disassembly-reassembly processes play a central role in preserving epigenetic information, thus ensuring transcriptional fidelity. The histone chaperone FACT performs key functions in nucleosome disassembly, maintenance, and reassembly during transcription in chromatin. Recent structural studies of transcribing RNA polymerase II complexed with nucleosomes have provided structural insights into transcription elongation on chromatin. Here, we review the structural transitions of the nucleosome during transcription.
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Affiliation(s)
- 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
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Haruhiko Ehara
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Shun-Ichi Sekine
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - 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
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
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4
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Kay RR, Weijer CJ. Jeffrey G. Williams (1948-2022): a pioneer molecular biologist in development. Development 2022. [DOI: 10.1242/dev.201254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Robert R. Kay
- MRC Laboratory of Molecular Biology 1 , Francis Crick Avenue, Cambridge, CB1 0QH , UK
| | - Cornelis J. Weijer
- School of Life Sciences, University of Dundee 2 , Dowstreet, Dundee, DD1 5EH , UK
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5
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Hsieh LJ, Gourdet MA, Moore CM, Muñoz EN, Gamarra N, Ramani V, Narlikar GJ. A hexasome is the preferred substrate for the INO80 chromatin remodeling complex, allowing versatility of function. Mol Cell 2022; 82:2098-2112.e4. [PMID: 35597239 PMCID: PMC9351570 DOI: 10.1016/j.molcel.2022.04.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 12/10/2021] [Accepted: 04/20/2022] [Indexed: 10/18/2022]
Abstract
The critical role of the INO80 chromatin remodeling complex in transcription is commonly attributed to its nucleosome sliding activity. Here, we have found that INO80 prefers to mobilize hexasomes over nucleosomes. INO80's preference for hexasomes reaches up to ∼60 fold when flanking DNA overhangs approach ∼18-bp linkers in yeast gene bodies. Correspondingly, deletion of INO80 significantly affects the positions of hexasome-sized particles within yeast genes in vivo. Our results raise the possibility that INO80 promotes nucleosome sliding by dislodging an H2A-H2B dimer, thereby making a nucleosome transiently resemble a hexasome. We propose that this mechanism allows INO80 to rapidly mobilize nucleosomes at promoters and hexasomes within gene bodies. Rapid repositioning of hexasomes that are generated in the wake of transcription may mitigate spurious transcription. More generally, such versatility may explain how INO80 regulates chromatin architecture during the diverse processes of transcription, replication, and repair.
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Affiliation(s)
- Laura J Hsieh
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Muryam A Gourdet
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Camille M Moore
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Elise N Muñoz
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Nathan Gamarra
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Vijay Ramani
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Geeta J Narlikar
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
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6
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Dao HT, Liu H, Mashtalir N, Kadoch C, Muir TW. Synthesis of Oriented Hexasomes and Asymmetric Nucleosomes Using a Template Editing Process. J Am Chem Soc 2022; 144:2284-2291. [PMID: 35081309 PMCID: PMC8935522 DOI: 10.1021/jacs.1c12420] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Nucleosomes, the structural building blocks of chromatin, possess 2-fold pseudo symmetry which can be broken through differential modification or removal of one copy of a pair of sister histones. The resultant asymmetric nucleosomes and hexasomes have been implicated in gene regulation, yet the use of these noncanonical substrates in chromatin biochemistry is limited, owing to the lack of efficient methods for their preparation. Here, we report a strategy that allows the orientation of these asymmetric species to be tightly controlled relative to the underlying DNA sequence. Our approach is based on the use of truncated DNA templates to assemble oriented hexasomes followed by DNA ligation and, in the case of asymmetric nucleosomes, addition of the missing heterotypic histones. We show that this approach is compatible with multiple nucleosome positioning sequences, allowing the generation of desymmetrized mononucleosomes and oligonucleosomes with varied DNA overhangs and heterotypic histone H2A/H2B dimer compositions. Using this technology, we examine the functional consequences of asymmetry on BRG1/BRM associated factor (BAF) complex-mediated chromatin remodeling. Our results indicate that cancer-associated histone mutations can reprogram the inherent activity of BAF chromatin remodeling to induce aberrant chromatin structure.
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Affiliation(s)
- Hai T. Dao
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Hengyuan Liu
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Nazar Mashtalir
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02215, United States,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Cigall Kadoch
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02215, United States,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Tom W. Muir
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States,Corresponding Author: Tom Muir - Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States,
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7
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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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8
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Casati P, Gomez MS. Chromatin dynamics during DNA damage and repair in plants: new roles for old players. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4119-4131. [PMID: 33206978 DOI: 10.1093/jxb/eraa551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 11/12/2020] [Indexed: 06/11/2023]
Abstract
The genome of plants is organized into chromatin. The chromatin structure regulates the rates of DNA metabolic processes such as replication, transcription, DNA recombination, and repair. Different aspects of plant growth and development are regulated by changes in chromatin status by the action of chromatin-remodeling activities. Recent data have also shown that many of these chromatin-associated proteins participate in different aspects of the DNA damage response, regulating DNA damage and repair, cell cycle progression, programmed cell death, and entry into the endocycle. In this review, we present different examples of proteins and chromatin-modifying enzymes with roles during DNA damage responses, demonstrating that rapid changes in chromatin structure are essential to maintain genome stability.
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Affiliation(s)
- Paula Casati
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha, Rosario, Argentina
| | - Maria Sol Gomez
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolas Cabrera, Cantoblanco, Madrid, Spain
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9
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Jiang Z, Zhang B. On the role of transcription in positioning nucleosomes. PLoS Comput Biol 2021; 17:e1008556. [PMID: 33417594 PMCID: PMC7819601 DOI: 10.1371/journal.pcbi.1008556] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 01/21/2021] [Accepted: 11/23/2020] [Indexed: 12/12/2022] Open
Abstract
Nucleosome positioning is crucial for the genome’s function. Though the role of DNA sequence in positioning nucleosomes is well understood, a detailed mechanistic understanding on the impact of transcription remains lacking. Using numerical simulations, we investigated the dependence of nucleosome density profiles on transcription level across multiple species. We found that the low nucleosome affinity of yeast, but not mouse, promoters contributes to the formation of phased nucleosomes arrays for inactive genes. For the active genes, a heterogeneous distribution of +1 nucleosomes, caused by a tug-of-war between two types of remodeling enzymes, is essential for reproducing their density profiles. In particular, while positioning enzymes are known to remodel the +1 nucleosome and align it toward the transcription start site (TSS), spacer enzymes that use a pair of nucleosomes as their substrate can shift the nucleosome array away from the TSS. Competition between these enzymes results in two types of nucleosome density profiles with well- and ill-positioned +1 nucleosome. Finally, we showed that Pol II assisted histone exchange, if occurring at a fast speed, can abolish the impact of remodeling enzymes. By elucidating the role of individual factors, our study reconciles the seemingly conflicting results on the overall impact of transcription in positioning nucleosomes across species. Nucleosome positioning plays a key role in the genome’s function by regulating the accessibility of protein binding sites as well as higher-order chromatin organization. Though significant progress has been made towards studying the role of DNA sequence in positioning the nucleosomes, our understanding on the impact of transcription lags behind. Our study uses kinetic simulations to explore the role of DNA sequence specificity, transcription factor binding, enzyme remodeling, and Pol II elongation in positioning nucleosomes. It suggests that the differences in nucleosome density profiles observed at various transcription levels in yeast and mouse embryonic stem cells can be understood from a tug-of-war between two types of remodeling enzymes.
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Affiliation(s)
- Zhongling Jiang
- Departments of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Bin Zhang
- Departments of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
- * E-mail:
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10
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Huynh MT, Yadav SP, Reese JC, Lee TH. Nucleosome Dynamics during Transcription Elongation. ACS Chem Biol 2020; 15:3133-3142. [PMID: 33263994 DOI: 10.1021/acschembio.0c00617] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The nucleosome is the basic packing unit of the eukaryotic genome. Dynamic interactions between DNA and histones in the nucleosome are the molecular basis of gene accessibility regulation that governs the kinetics of various DNA-templated processes such as transcription elongation by RNA Polymerase II (Pol II). On the basis of single-molecule FRET measurements with chemically modified histones, we investigated the nucleosome dynamics during transcription elongation and how it is affected by histone acetylation at H3 K56 and the histone chaperone Nap1, both of which can affect DNA-histone interactions. We observed that H3K56 acetylation dramatically shortens the pause duration of Pol II near the entry region of the nucleosome, while Nap1 induces no noticeable difference. We also found that the elongation rate of Pol II through the nucleosome is unaffected by the acetylation or Nap1. These results indicate that H3K56 acetylation facilitates Pol II translocation through the nucleosome by assisting paused Pol II to resume and that Nap1 does not affect Pol II progression. Following transcription, only a small fraction of nucleosomes remain intact, which is unaffected by H3K56 acetylation or Nap1. These results suggest that (i) spontaneous nucleosome opening enables Pol II progression, (ii) Pol II mediates nucleosome reassembly very inefficiently, and (iii) Nap1 in the absence of other factors does not promote nucleosome disassembly or reassembly during transcription.
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11
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Formosa T, Winston F. The role of FACT in managing chromatin: disruption, assembly, or repair? Nucleic Acids Res 2020; 48:11929-11941. [PMID: 33104782 PMCID: PMC7708052 DOI: 10.1093/nar/gkaa912] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/01/2020] [Accepted: 10/05/2020] [Indexed: 12/20/2022] Open
Abstract
FACT (FAcilitates Chromatin Transcription) has long been considered to be a transcription elongation factor whose ability to destabilize nucleosomes promotes RNAPII progression on chromatin templates. However, this is just one function of this histone chaperone, as FACT also functions in DNA replication. While broadly conserved among eukaryotes and essential for viability in many organisms, dependence on FACT varies widely, with some differentiated cells proliferating normally in its absence. It is therefore unclear what the core functions of FACT are, whether they differ in different circumstances, and what makes FACT essential in some situations but not others. Here, we review recent advances and propose a unifying model for FACT activity. By analogy to DNA repair, we propose that the ability of FACT to both destabilize and assemble nucleosomes allows it to monitor and restore nucleosome integrity as part of a system of chromatin repair, in which disruptions in the packaging of DNA are sensed and returned to their normal state. The requirement for FACT then depends on the level of chromatin disruption occurring in the cell, and the cell's ability to tolerate packaging defects. The role of FACT in transcription would then be just one facet of a broader system for maintaining chromatin integrity.
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Affiliation(s)
- Tim Formosa
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Fred Winston
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
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12
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Xu J, Wang W, Xu L, Chen JY, Chong J, Oh J, Leschziner AE, Fu XD, Wang D. Cockayne syndrome B protein acts as an ATP-dependent processivity factor that helps RNA polymerase II overcome nucleosome barriers. Proc Natl Acad Sci U S A 2020; 117:25486-25493. [PMID: 32989164 PMCID: PMC7568279 DOI: 10.1073/pnas.2013379117] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
While loss-of-function mutations in Cockayne syndrome group B protein (CSB) cause neurological diseases, this unique member of the SWI2/SNF2 family of chromatin remodelers has been broadly implicated in transcription elongation and transcription-coupled DNA damage repair, yet its mechanism remains largely elusive. Here, we use a reconstituted in vitro transcription system with purified polymerase II (Pol II) and Rad26, a yeast ortholog of CSB, to study the role of CSB in transcription elongation through nucleosome barriers. We show that CSB forms a stable complex with Pol II and acts as an ATP-dependent processivity factor that helps Pol II across a nucleosome barrier. This noncanonical mechanism is distinct from the canonical modes of chromatin remodelers that directly engage and remodel nucleosomes or transcription elongation factors that facilitate Pol II nucleosome bypass without hydrolyzing ATP. We propose a model where CSB facilitates gene expression by helping Pol II bypass chromatin obstacles while maintaining their structures.
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Affiliation(s)
- Jun Xu
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093
| | - Wei Wang
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093
| | - Liang Xu
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093
| | - Jia-Yu Chen
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093
| | - Jenny Chong
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093
| | - Juntaek Oh
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093
| | - Andres E Leschziner
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093
- Section of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093
| | - Xiang-Dong Fu
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093
| | - Dong Wang
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093;
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093
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13
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Abstract
Histone variants regulate chromatin accessibility and gene transcription. Given their distinct properties and functions, histone varint substitutions allow for profound alteration of nucleosomal architecture and local chromatin landscape. Skeletal myogenesis driven by the key transcription factor MyoD is characterized by precise temporal regulation of myogenic genes. Timed substitution of variants within the nucleosomes provides a powerful means to ensure sequential expression of myogenic genes. Indeed, growing evidence has shown H3.3, H2A.Z, macroH2A, and H1b to be critical for skeletal myogenesis. However, the relative importance of various histone variants and their associated chaperones in myogenesis is not fully appreciated. In this review, we summarize the role that histone variants play in altering chromatin landscape to ensure proper muscle differentiation. The temporal regulation and cross talk between histones variants and their chaperones in conjunction with other forms of epigenetic regulation could be critical to understanding myogenesis and their involvement in myopathies.
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Affiliation(s)
- Nandini Karthik
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore , Singapore
| | - Reshma Taneja
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore , Singapore
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14
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Hainer SJ, Kaplan CD. Specialized RSC: Substrate Specificities for a Conserved Chromatin Remodeler. Bioessays 2020; 42:e2000002. [PMID: 32490565 PMCID: PMC7329613 DOI: 10.1002/bies.202000002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/11/2020] [Indexed: 01/16/2023]
Abstract
The remodel the structure of chromatin (RSC) nucleosome remodeling complex is a conserved chromatin regulator with roles in chromatin organization, especially over nucleosome depleted regions therefore functioning in gene expression. Recent reports in Saccharomyces cerevisiae have identified specificities in RSC activity toward certain types of nucleosomes. RSC has now been shown to preferentially evict nucleosomes containing the histone variant H2A.Z in vitro. Furthermore, biochemical activities of distinct RSC complexes has been found to differ when their nucleosome substrate is partially unraveled. Mammalian BAF complexes, the homologs of yeast RSC and SWI/SNF complexes, are also linked to nucleosomes with H2A.Z, but this relationship may be complex and extent of conservation remains to be determined. The interplay of remodelers with specific nucleosome substrates and regulation of remodeler outcomes by nucleosome composition are tantalizing questions given the wave of structural data emerging for RSC and other SWI/SNF family remodelers.
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Affiliation(s)
- Sarah J Hainer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Craig D Kaplan
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
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15
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Kujirai T, Kurumizaka H. Transcription through the nucleosome. Curr Opin Struct Biol 2020; 61:42-49. [DOI: 10.1016/j.sbi.2019.10.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/17/2019] [Accepted: 10/22/2019] [Indexed: 11/28/2022]
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16
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Patel AB, Moore CM, Greber BJ, Luo J, Zukin SA, Ranish J, Nogales E. Architecture of the chromatin remodeler RSC and insights into its nucleosome engagement. eLife 2019; 8:e54449. [PMID: 31886770 PMCID: PMC6959994 DOI: 10.7554/elife.54449] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 12/23/2019] [Indexed: 12/21/2022] Open
Abstract
Eukaryotic DNA is packaged into nucleosome arrays, which are repositioned by chromatin remodeling complexes to control DNA accessibility. The Saccharomyces cerevisiae RSC (Remodeling the Structure of Chromatin) complex, a member of the SWI/SNF chromatin remodeler family, plays critical roles in genome maintenance, transcription, and DNA repair. Here, we report cryo-electron microscopy (cryo-EM) and crosslinking mass spectrometry (CLMS) studies of yeast RSC complex and show that RSC is composed of a rigid tripartite core and two flexible lobes. The core structure is scaffolded by an asymmetric Rsc8 dimer and built with the evolutionarily conserved subunits Sfh1, Rsc6, Rsc9 and Sth1. The flexible ATPase lobe, composed of helicase subunit Sth1, Arp7, Arp9 and Rtt102, is anchored to this core by the N-terminus of Sth1. Our cryo-EM analysis of RSC bound to a nucleosome core particle shows that in addition to the expected nucleosome-Sth1 interactions, RSC engages histones and nucleosomal DNA through one arm of the core structure, composed of the Rsc8 SWIRM domains, Sfh1 and Npl6. Our findings provide structural insights into the conserved assembly process for all members of the SWI/SNF family of remodelers, and illustrate how RSC selects, engages, and remodels nucleosomes.
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Affiliation(s)
- Avinash B Patel
- Biophysics Graduate GroupUniversity of California, BerkeleyBerkeleyUnited States
- Molecular Biophysics and Integrative Bio-Imaging DivisionLawrence Berkeley National LaboratoryBerkeleyUnited States
| | - Camille M Moore
- Molecular and Cell Biology DepartmentUniversity of California, BerkeleyBerkeleyUnited States
| | - Basil J Greber
- Molecular Biophysics and Integrative Bio-Imaging DivisionLawrence Berkeley National LaboratoryBerkeleyUnited States
- California Institute for Quantitative Biology (QB3)University of California, BerkeleyBerkeleyUnited States
| | - Jie Luo
- The Institute for Systems BiologySeattleUnited States
| | - Stefan A Zukin
- Chemistry DepartmentUniversity of California, BerkeleyBerkeleyUnited States
| | - Jeff Ranish
- The Institute for Systems BiologySeattleUnited States
| | - Eva Nogales
- Molecular Biophysics and Integrative Bio-Imaging DivisionLawrence Berkeley National LaboratoryBerkeleyUnited States
- Molecular and Cell Biology DepartmentUniversity of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biology (QB3)University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
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17
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Krajewski WA, Li J, Dou Y. Effects of histone H2B ubiquitylation on the nucleosome structure and dynamics. Nucleic Acids Res 2019; 46:7631-7642. [PMID: 29931239 PMCID: PMC6125632 DOI: 10.1093/nar/gky526] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 05/25/2018] [Indexed: 01/01/2023] Open
Abstract
DNA in nucleosomes has restricted nucleosome dynamics and is refractory to DNA-templated processes. Histone post-translational modifications play important roles in regulating DNA accessibility in nucleosomes. Whereas most histone modifications function either by mitigating the electrostatic shielding of histone tails or by recruiting 'reader' proteins, we show that ubiquitylation of H2B K34, which is located in a tight space protected by two coils of DNA superhelix, is able to directly influence the canonical nucleosome conformation via steric hindrances by ubiquitin groups. H2B K34 ubiquitylation significantly enhances nucleosome dynamics and promotes generation of hexasomes both with symmetrically or asymmetrically modified nucleosomes. Our results indicate a direct mechanism by which a histone modification regulates the chromatin structural states.
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Affiliation(s)
- Wladyslaw A Krajewski
- N.K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova Str. 26, Moscow, 119334, Russia.,Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jiabin Li
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Yali Dou
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
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18
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Abstract
Repair of damaged DNA plays a crucial role in maintaining genomic integrity and normal cell function. The base excision repair (BER) pathway is primarily responsible for removing modified nucleobases that would otherwise cause deleterious and mutagenic consequences and lead to disease. The BER process is initiated by a DNA glycosylase, which recognizes and excises the target nucleobase lesion, and is completed via downstream enzymes acting in a well-coordinated manner. A majority of our current understanding about how BER enzymes function comes from in vitro studies using free duplex DNA as a simplified model. In eukaryotes, however, BER is challenged by the packaging of genomic DNA into chromatin. The fundamental structural repeating unit of chromatin is the nucleosome, which presents a more complex substrate context than free duplex DNA for repair. In this chapter, we discuss how BER enzymes, particularly glycosylases, engage in the context of packaged DNA with insights obtained from both in vivo and in vitro studies. Furthermore, we review factors and mechanisms that can modify chromatin architecture and/or influence DNA accessibility to BER machinery, such as the geometric location of the damage site, nucleosomal DNA unwrapping, histone post-translational modifications, histone variant incorporation, and chromatin remodeling.
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Affiliation(s)
- Chuxuan Li
- Department of Chemistry, Brown University, Providence, RI, United States
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, RI, United States.
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19
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Cakiroglu A, Clapier CR, Ehrensberger AH, Darbo E, Cairns BR, Luscombe NM, Svejstrup JQ. Genome-wide reconstitution of chromatin transactions reveals that RSC preferentially disrupts H2AZ-containing nucleosomes. Genome Res 2019; 29:988-998. [PMID: 31097474 PMCID: PMC6581049 DOI: 10.1101/gr.243139.118] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 05/08/2019] [Indexed: 12/03/2022]
Abstract
Chromatin transactions are typically studied in vivo, or in vitro using artificial chromatin lacking the epigenetic complexity of the natural material. Attempting to bridge the gap between these approaches, we established a system for isolating the yeast genome as a library of mononucleosomes harboring the natural epigenetic signature, suitable for biochemical manipulation. Combined with deep sequencing, this library was used to investigate the stability of individual nucleosomes and, as proof of principle, the nucleosome preference of the chromatin remodeling complex, RSC. This approach uncovered a distinct preference of RSC for nucleosomes derived from regions with a high density of histone variant H2AZ, and this preference is indeed markedly diminished using nucleosomes from cells lacking H2AZ. The preference for H2AZ remodeling/nucleosome ejection can also be reconstituted with recombinant nucleosome arrays. Together, our data indicate that, despite being separated from their genomic context, individual nucleosomes can retain their original identity as promoter- or transcription start site (TSS)-nucleosomes. Besides shedding new light on substrate preference of the chromatin remodeler RSC, the simple experimental system outlined here should be generally applicable to the study of chromatin transactions.
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Affiliation(s)
- Aylin Cakiroglu
- Bioinformatics and Computational Biology Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Cedric R Clapier
- Department of Oncological Sciences, Huntsman Cancer Institute, and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Andreas H Ehrensberger
- Bioinformatics and Computational Biology Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Elodie Darbo
- Bioinformatics and Computational Biology Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Bradley R Cairns
- Department of Oncological Sciences, Huntsman Cancer Institute, and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Nicholas M Luscombe
- Bioinformatics and Computational Biology Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
- UCL Genetics Institute, Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Jesper Q Svejstrup
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
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20
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McCullough LL, Pham TH, Parnell TJ, Connell Z, Chandrasekharan MB, Stillman DJ, Formosa T. Establishment and Maintenance of Chromatin Architecture Are Promoted Independently of Transcription by the Histone Chaperone FACT and H3-K56 Acetylation in Saccharomyces cerevisiae. Genetics 2019; 211:877-892. [PMID: 30679261 PMCID: PMC6404263 DOI: 10.1534/genetics.118.301853] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 01/14/2019] [Indexed: 12/16/2022] Open
Abstract
FACT (FAcilitates Chromatin Transcription/Transactions) is a histone chaperone that can destabilize or assemble nucleosomes. Acetylation of histone H3-K56 weakens a histone-DNA contact that is central to FACT activity, suggesting that this modification could affect FACT functions. We tested this by asking how mutations of H3-K56 and FACT affect nucleosome reorganization activity in vitro, and chromatin integrity and transcript output in vivo Mimics of unacetylated or permanently acetylated H3-K56 had different effects on FACT activity as expected, but the same mutations had surprisingly similar effects on global transcript levels. The results are consistent with emerging models that emphasize FACT's importance in establishing global chromatin architecture prior to transcription, promoting transitions among different states as transcription profiles change, and restoring chromatin integrity after it is disturbed. Optimal FACT activity required the availability of both modified and unmodified states of H3-K56. Perturbing this balance was especially detrimental for maintaining repression of genes with high nucleosome occupancy over their promoters and for blocking antisense transcription at the +1 nucleosome. The results reveal a complex collaboration between H3-K56 modification status and multiple FACT functions, and support roles for nucleosome reorganization by FACT before, during, and after transcription.
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Affiliation(s)
- Laura L McCullough
- Department of Biochemistry, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - Trang H Pham
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - Timothy J Parnell
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - Zaily Connell
- Department of Biochemistry, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - Mahesh B Chandrasekharan
- Department of Radiation Oncology, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - David J Stillman
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - Tim Formosa
- Department of Biochemistry, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
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21
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Hsu KW, Chow SY, Su BY, Lu YH, Chen CJ, Chen WL, Cheng MY, Fan HF. The synergy between RSC, Nap1 and adjacent nucleosome in nucleosome remodeling. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2018; 1862:129-140. [PMID: 30593928 DOI: 10.1016/j.bbagrm.2018.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/23/2018] [Accepted: 11/30/2018] [Indexed: 12/29/2022]
Abstract
Eukaryotes have evolved a specific strategy to package DNA. The nucleosome is a 147-base-pair DNA segment wrapped around histone core proteins that plays important roles regulating DNA-dependent biosynthesis and gene expression. Chromatin remodeling complexes (RSC, Remodel the Structure of Chromatin) hydrolyze ATP to perturb DNA-histone contacts, leading to nucleosome sliding and ejection. Here, we utilized tethered particle motion (TPM) experiments to investigate the mechanism of RSC-mediated nucleosome remodeling in detail. We observed ATP-dependent RSC-mediated DNA looping and nucleosome ejection along individual mononucleosomes and dinucleosomes. We found that nucleosome assembly protein 1 (Nap1) enhanced RSC-mediated nucleosome ejection in a two-step disassembly manner from dinucleosomes but not from mononucleosomes. Based on this work, we provide an entire reaction scheme for the RSC-mediated nucleosome remodeling process that includes DNA looping, nucleosome ejection, the influence of adjacent nucleosomes, and the coordinated action between Nap1 and RSC.
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Affiliation(s)
- Kuan-Wei Hsu
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan
| | - Sih-Yao Chow
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan
| | - Bo-Yu Su
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan
| | - Yi-Han Lu
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan
| | - Cyuan-Ji Chen
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan
| | - Wen-Ling Chen
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan
| | - Ming-Yuan Cheng
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan
| | - Hsiu-Fang Fan
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taiwan.
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22
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Brahma S, Henikoff S. RSC-Associated Subnucleosomes Define MNase-Sensitive Promoters in Yeast. Mol Cell 2018; 73:238-249.e3. [PMID: 30554944 PMCID: PMC6475595 DOI: 10.1016/j.molcel.2018.10.046] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/04/2018] [Accepted: 10/30/2018] [Indexed: 02/07/2023]
Abstract
The classic view of nucleosome organization at active promoters is that two well-positioned nucleosomes flank a nucleosome-depleted region (NDR). However, this view has been recently disputed by contradictory reports as to whether wider (≳150 bp) NDRs instead contain unstable, micrococcal nuclease-sensitive ("fragile") nucleosomal particles. To determine the composition of fragile particles, we introduce CUT&RUN.ChIP, in which targeted nuclease cleavage and release is followed by chromatin immunoprecipitation. We find that fragile particles represent the occupancy of the RSC (remodeling the structure of chromatin) nucleosome remodeling complex and RSC-bound, partially unwrapped nucleosomal intermediates. We also find that general regulatory factors (GRFs) bind to partially unwrapped nucleosomes at these promoters. We propose that RSC binding and its action cause nucleosomes to unravel, facilitate subsequent binding of GRFs, and constitute a dynamic cycle of nucleosome deposition and clearance at the subset of wide Pol II promoter NDRs.
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Affiliation(s)
- Sandipan Brahma
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Steven Henikoff
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Howard Hughes Medical Institute, USA.
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23
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The histone chaperone NAP1L3 is required for haematopoietic stem cell maintenance and differentiation. Sci Rep 2018; 8:11202. [PMID: 30046127 PMCID: PMC6060140 DOI: 10.1038/s41598-018-29518-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 07/12/2018] [Indexed: 01/04/2023] Open
Abstract
Nucleosome assembly proteins (NAPs) are histone chaperones with an important role in chromatin structure and epigenetic regulation of gene expression. We find that high gene expression levels of mouse Nap1l3 are restricted to haematopoietic stem cells (HSCs) in mice. Importantly, with shRNA or CRISPR-Cas9 mediated loss of function of mouse Nap1l3 and with overexpression of the gene, the number of colony-forming cells and myeloid progenitor cells in vitro are reduced. This manifests as a striking decrease in the number of HSCs, which reduces their reconstituting activities in vivo. Downregulation of human NAP1L3 in umbilical cord blood (UCB) HSCs impairs the maintenance and proliferation of HSCs both in vitro and in vivo. NAP1L3 downregulation in UCB HSCs causes an arrest in the G0 phase of cell cycle progression and induces gene expression signatures that significantly correlate with downregulation of gene sets involved in cell cycle regulation, including E2F and MYC target genes. Moreover, we demonstrate that HOXA3 and HOXA5 genes are markedly upregulated when NAP1L3 is suppressed in UCB HSCs. Taken together, our findings establish an important role for NAP1L3 in HSC homeostasis and haematopoietic differentiation.
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24
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Wang T, Liu Y, Edwards G, Krzizike D, Scherman H, Luger K. The histone chaperone FACT modulates nucleosome structure by tethering its components. Life Sci Alliance 2018; 1:e201800107. [PMID: 30456370 PMCID: PMC6238592 DOI: 10.26508/lsa.201800107] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 06/29/2018] [Accepted: 06/29/2018] [Indexed: 11/24/2022] Open
Abstract
The histone chaperone FACT functions by tethering partial components of the nucleosome, thereby assisting nucleosome disassembly and reassembly during transcription. Human FAcilitates Chromatin Transcription (hFACT) is a conserved histone chaperone that was originally described as a transcription elongation factor with potential nucleosome assembly functions. Here, we show that FACT has moderate tetrasome assembly activity but facilitates H2A–H2B deposition to form hexasomes and nucleosomes. In the process, FACT tethers components of the nucleosome through interactions with H2A–H2B, resulting in a defined intermediate complex comprising FACT, a histone hexamer, and DNA. Free DNA extending from the tetrasome then competes FACT off H2A–H2B, thereby promoting hexasome and nucleosome formation. Our studies provide mechanistic insight into how FACT may stabilize partial nucleosome structures during transcription or nucleosome assembly, seemingly facilitating both nucleosome disassembly and nucleosome assembly.
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Affiliation(s)
- Tao Wang
- Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO, USA.,Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Yang Liu
- Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO, USA
| | - Garrett Edwards
- Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO, USA
| | - Daniel Krzizike
- Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO, USA.,Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Hataichanok Scherman
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA.,Institute for Genome Architecture and Function, Colorado State University, Fort Collins, CO, USA
| | - Karolin Luger
- Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO, USA.,Institute for Genome Architecture and Function, Colorado State University, Fort Collins, CO, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
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25
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Hamilton PD, Andley UP. In vitro interactions of histones and α-crystallin. Biochem Biophys Rep 2018; 15:7-12. [PMID: 30023439 PMCID: PMC6047474 DOI: 10.1016/j.bbrep.2018.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 11/15/2022] Open
Abstract
The aggregation of crystallins in lenses is associated with cataract formation. We previously reported that mutant crystallins are associated with an increased abundance of histones in knock-in and knockout mouse models. However, very little is known about the specific interactions between lens crystallins and histones. Here, we performed in vitro analyses to determine whether α-crystallin interacts with histones directly. Isothermal titration calorimetry revealed a strong histone–α-crystallin binding with a Kd of 4 × 10−7 M, and the thermodynamic parameters suggested that the interaction was both entropy and enthalpy driven. Size-exclusion chromatography further showed that histone–α-crystallin complexes are water soluble but become water insoluble as the concentration of histones is increased. Right-angle light scattering measurements of the water-soluble fractions of histone–α-crystallin mixtures showed a decrease in the oligomeric molecular weight of α-crystallin, indicating that histones alter the oligomerization of α-crystallin. Taken together, these findings reveal for the first time that histones interact with and affect the solubility and aggregation of α-crystallin, indicating that the interaction between α-crystallin and histones in the lens is functionally important. Histones are upregulated in α-crystallin mutant mice with hereditary cataracts. Isothermal titration calorimetry reveals histones and α-crystallin interact. These interactions are enthalpy and entropy driven. Histones affect the solubility and aggregation behavior of α-crystallin in vitro.
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Affiliation(s)
- Paul D Hamilton
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Usha P Andley
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
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26
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Abstract
The nucleosome serves as a general gene repressor, preventing all initiation of transcription except that which is brought about by specific positive regulatory mechanisms. The positive mechanisms begin with chromatin-remodeling by complexes that slide, disrupt, or otherwise alter the structure and organization of nucleosomes. RSC in yeast and its counterpart PBAF in human cells are the major remodeling complexes for transcription. RSC creates a nucleosome-free region in front of a gene, flanked by strongly positioned +1 and -1 nucleosomes, with the transcription start site typically 10-15 bp inside the border of the +1 nucleosome. RSC also binds stably to nucleosomes harboring regulatory elements and to +1 nucleosomes, perturbing their structures in a manner that partially exposes their DNA sequences. The cryo-electron microscope structure of a RSC-nucleosome complex reveals such a structural perturbation, with the DNA largely unwrapped from the nucleosome and likely interacting with a positively charged surface of RSC. Such unwrapping both exposes the DNA and enables its translocation across the histone octamer of the nucleosome by an ATP-dependent activity of RSC. Genetic studies have revealed additional roles of RSC in DNA repair, chromosome segregation, and other chromosomal DNA transactions. These functions of RSC likely involve the same fundamental activities, DNA unwrapping and DNA translocation.
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27
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Ramachandran S, Ahmad K, Henikoff S. Transcription and Remodeling Produce Asymmetrically Unwrapped Nucleosomal Intermediates. Mol Cell 2017; 68:1038-1053.e4. [PMID: 29225036 PMCID: PMC6421108 DOI: 10.1016/j.molcel.2017.11.015] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 08/29/2017] [Accepted: 11/10/2017] [Indexed: 12/29/2022]
Abstract
Nucleosomes are disrupted during transcription and other active processes, but the structural intermediates during nucleosome disruption in vivo are unknown. To identify intermediates, we mapped subnucleosomal protections in Drosophila cells using Micrococcal Nuclease followed by sequencing. At the first nucleosome position downstream of the transcription start site, we identified unwrapped intermediates, including hexasomes that lack either proximal or distal contacts. Inhibiting topoisomerases or depleting histone chaperones increased unwrapping, whereas inhibiting release of paused RNAPII or reducing RNAPII elongation decreased unwrapping. Our results indicate that positive torsion generated by elongating RNAPII causes transient loss of histone-DNA contacts. Using this mapping approach, we found that nucleosomes flanking human CTCF insulation sites are similarly disrupted. We also identified diagnostic subnucleosomal particle remnants in cell-free human DNA data as a relic of transcribed genes from apoptosing cells. Thus identification of subnucleosomal fragments from nuclease protection data represents a general strategy for structural epigenomics.
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Affiliation(s)
- Srinivas Ramachandran
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Howard Hughes Medical Institute, Seattle, WA 98109, USA
| | - Kami Ahmad
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Steven Henikoff
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Howard Hughes Medical Institute, Seattle, WA 98109, USA.
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28
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Gutiérrez G, Millán-Zambrano G, Medina DA, Jordán-Pla A, Pérez-Ortín JE, Peñate X, Chávez S. Subtracting the sequence bias from partially digested MNase-seq data reveals a general contribution of TFIIS to nucleosome positioning. Epigenetics Chromatin 2017; 10:58. [PMID: 29212533 PMCID: PMC5719526 DOI: 10.1186/s13072-017-0165-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/29/2017] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND TFIIS stimulates RNA cleavage by RNA polymerase II and promotes the resolution of backtracking events. TFIIS acts in the chromatin context, but its contribution to the chromatin landscape has not yet been investigated. Co-transcriptional chromatin alterations include subtle changes in nucleosome positioning, like those expected to be elicited by TFIIS, which are elusive to detect. The most popular method to map nucleosomes involves intensive chromatin digestion by micrococcal nuclease (MNase). Maps based on these exhaustively digested samples miss any MNase-sensitive nucleosomes caused by transcription. In contrast, partial digestion approaches preserve such nucleosomes, but introduce noise due to MNase sequence preferences. A systematic way of correcting this bias for massively parallel sequencing experiments is still missing. RESULTS To investigate the contribution of TFIIS to the chromatin landscape, we developed a refined nucleosome-mapping method in Saccharomyces cerevisiae. Based on partial MNase digestion and a sequence-bias correction derived from naked DNA cleavage, the refined method efficiently mapped nucleosomes in promoter regions rich in MNase-sensitive structures. The naked DNA correction was also important for mapping gene body nucleosomes, particularly in those genes whose core promoters contain a canonical TATA element. With this improved method, we analyzed the global nucleosomal changes caused by lack of TFIIS. We detected a general increase in nucleosomal fuzziness and more restricted changes in nucleosome occupancy, which concentrated in some gene categories. The TATA-containing genes were preferentially associated with decreased occupancy in gene bodies, whereas the TATA-like genes did so with increased fuzziness. The detected chromatin alterations correlated with functional defects in nascent transcription, as revealed by genomic run-on experiments. CONCLUSIONS The combination of partial MNase digestion and naked DNA correction of the sequence bias is a precise nucleosomal mapping method that does not exclude MNase-sensitive nucleosomes. This method is useful for detecting subtle alterations in nucleosome positioning produced by lack of TFIIS. Their analysis revealed that TFIIS generally contributed to nucleosome positioning in both gene promoters and bodies. The independent effect of lack of TFIIS on nucleosome occupancy and fuzziness supports the existence of alternative chromatin dynamics during transcription elongation.
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Affiliation(s)
| | - Gonzalo Millán-Zambrano
- Departamento de Genética, Universidad de Sevilla, Seville, Spain.,Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville, Spain.,The Gurdon Institute, University of Cambridge, Cambridge, UK
| | - Daniel A Medina
- Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Valencia, Spain.,Department of Chemical and Bioprocess Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Antonio Jordán-Pla
- Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Valencia, Spain.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - José E Pérez-Ortín
- Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Valencia, Spain
| | - Xenia Peñate
- Departamento de Genética, Universidad de Sevilla, Seville, Spain. .,Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville, Spain.
| | - Sebastián Chávez
- Departamento de Genética, Universidad de Sevilla, Seville, Spain. .,Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville, Spain.
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29
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Imre L, Simándi Z, Horváth A, Fenyőfalvi G, Nánási P, Niaki EF, Hegedüs É, Bacsó Z, Weyemi U, Mauser R, Ausio J, Jeltsch A, Bonner W, Nagy L, Kimura H, Szabó G. Nucleosome stability measured in situ by automated quantitative imaging. Sci Rep 2017; 7:12734. [PMID: 28986581 PMCID: PMC5630628 DOI: 10.1038/s41598-017-12608-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/06/2017] [Indexed: 02/07/2023] Open
Abstract
Current approaches have limitations in providing insight into the functional properties of particular nucleosomes in their native molecular environment. Here we describe a simple and powerful method involving elution of histones using intercalators or salt, to assess stability features dependent on DNA superhelicity and relying mainly on electrostatic interactions, respectively, and measurement of the fraction of histones remaining chromatin-bound in the individual nuclei using histone type- or posttranslational modification- (PTM-) specific antibodies and automated, quantitative imaging. The method has been validated in H3K4me3 ChIP-seq experiments, by the quantitative assessment of chromatin loop relaxation required for nucleosomal destabilization, and by comparative analyses of the intercalator and salt induced release from the nucleosomes of different histones. The accuracy of the assay allowed us to observe examples of strict association between nucleosome stability and PTMs across cell types, differentiation state and throughout the cell-cycle in close to native chromatin context, and resolve ambiguities regarding the destabilizing effect of H2A.X phosphorylation. The advantages of the in situ measuring scenario are demonstrated via the marked effect of DNA nicking on histone eviction that underscores the powerful potential of topological relaxation in the epigenetic regulation of DNA accessibility.
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Affiliation(s)
- László Imre
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - Zoltán Simándi
- Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, H-4032, Hungary.,Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - Attila Horváth
- Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - György Fenyőfalvi
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - Péter Nánási
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - Erfaneh Firouzi Niaki
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - Éva Hegedüs
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - Zsolt Bacsó
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - Urbain Weyemi
- Center for Cancer Research National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - Rebekka Mauser
- Institute of Biochemistry, Stuttgart University, Stuttgart, Germany
| | - Juan Ausio
- University of Victoria, Department of Biochemistry, Victoria, BC, V8W 3P6, Canada
| | - Albert Jeltsch
- Institute of Biochemistry, Stuttgart University, Stuttgart, Germany
| | - William Bonner
- Center for Cancer Research National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - László Nagy
- Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, H-4032, Hungary.,Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA.,MTA-DE "Lendulet" Immunogenomics Research Group, University of Debrecen, Debrecen, Hungary
| | - Hiroshi Kimura
- Cell Biology Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Gábor Szabó
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, H-4032, Hungary.
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30
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Lee J, Lee TH. Single-Molecule Investigations on Histone H2A-H2B Dynamics in the Nucleosome. Biochemistry 2017; 56:977-985. [PMID: 28128545 DOI: 10.1021/acs.biochem.6b01252] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Nucleosomes impose physical barriers to DNA-templated processes, playing important roles in eukaryotic gene regulation. DNA is packaged into nucleosomes by histone proteins mainly through strong electrostatic interactions that can be modulated by various post-translational histone modifications. Investigating the dynamics of histone dissociation from the nucleosome and how it is altered upon histone modifications is important for understanding eukaryotic gene regulation mechanisms. In particular, histone H2A-H2B dimer displacement in the nucleosome is one of the most important and earliest steps of histone dissociation. Two conflicting hypotheses on the requirement for dimer displacement are that nucleosomal DNA needs to be unwrapped before a dimer can displace and that a dimer can displace without DNA unwrapping. In order to test the hypotheses, we employed three-color single-molecule FRET and monitored in a time-resolved manner the early kinetics of H2A-H2B dimer dissociation triggered by high salt concentration and by histone chaperone Nap1. The results reveal that dimer displacement requires DNA unwrapping in the vast majority of the nucleosomes in the salt-induced case, while dimer displacement precedes DNA unwrapping in >60% of the nucleosomes in the Nap1-mediated case. We also found that acetylation at histone H4K16 or H3K56 affects the kinetics of Nap1-mediated dimer dissociation and facilitates the process both kinetically and thermodynamically. On the basis of these results, we suggest a mechanism by which histone chaperone facilitates H2A-H2B dimer displacement from the histone core without requiring another factor to unwrap the nucleosomal DNA.
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Affiliation(s)
- Jaehyoun Lee
- Department of Chemistry, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Tae-Hee Lee
- Department of Chemistry, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
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31
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Abstract
Chromatin isolated from the chromosomal locus of the PHO5 gene of yeast in a transcriptionally repressed state was transcribed with 12 pure proteins (80 polypeptides): RNA polymerase II, six general transcription factors, TFIIS, the Pho4 gene activator protein, and the SAGA, SWI/SNF, and Mediator complexes. Contrary to expectation, a nucleosome occluding the TATA box and transcription start sites did not impede transcription but rather, enhanced it: the level of chromatin transcription was at least sevenfold greater than that of naked DNA, and chromatin gave patterns of transcription start sites closely similar to those occurring in vivo, whereas naked DNA gave many aberrant transcripts. Both histone acetylation and trimethylation of H3K4 (H3K4me3) were important for chromatin transcription. The nucleosome, long known to serve as a general gene repressor, thus also performs an important positive role in transcription.
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32
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Reddy BA, Jeronimo C, Robert F. Recent Perspectives on the Roles of Histone Chaperones in Transcription Regulation. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s40610-017-0049-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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33
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Hammond CM, Strømme CB, Huang H, Patel DJ, Groth A. Histone chaperone networks shaping chromatin function. Nat Rev Mol Cell Biol 2017; 18:141-158. [PMID: 28053344 DOI: 10.1038/nrm.2016.159] [Citation(s) in RCA: 347] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The association of histones with specific chaperone complexes is important for their folding, oligomerization, post-translational modification, nuclear import, stability, assembly and genomic localization. In this way, the chaperoning of soluble histones is a key determinant of histone availability and fate, which affects all chromosomal processes, including gene expression, chromosome segregation and genome replication and repair. Here, we review the distinct structural and functional properties of the expanding network of histone chaperones. We emphasize how chaperones cooperate in the histone chaperone network and via co-chaperone complexes to match histone supply with demand, thereby promoting proper nucleosome assembly and maintaining epigenetic information by recycling modified histones evicted from chromatin.
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Affiliation(s)
- Colin M Hammond
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Caroline B Strømme
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Hongda Huang
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Anja Groth
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
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34
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Levendosky RF, Sabantsev A, Deindl S, Bowman GD. The Chd1 chromatin remodeler shifts hexasomes unidirectionally. eLife 2016; 5. [PMID: 28032848 PMCID: PMC5226652 DOI: 10.7554/elife.21356] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 12/28/2016] [Indexed: 12/27/2022] Open
Abstract
Despite their canonical two-fold symmetry, nucleosomes in biological contexts are often asymmetric: functionalized with post-translational modifications (PTMs), substituted with histone variants, and even lacking H2A/H2B dimers. Here we show that the Widom 601 nucleosome positioning sequence can produce hexasomes in a specific orientation on DNA, providing a useful tool for interrogating chromatin enzymes and allowing for the generation of nucleosomes with precisely defined asymmetry. Using this methodology, we demonstrate that the Chd1 chromatin remodeler from Saccharomyces cerevisiae requires H2A/H2B on the entry side for sliding, and thus, unlike the back-and-forth sliding observed for nucleosomes, Chd1 shifts hexasomes unidirectionally. Chd1 takes part in chromatin reorganization surrounding transcribing RNA polymerase II (Pol II), and using asymmetric nucleosomes we show that ubiquitin-conjugated H2B on the entry side stimulates nucleosome sliding by Chd1. We speculate that biased nucleosome and hexasome sliding due to asymmetry contributes to the packing of arrays observed in vivo. DOI:http://dx.doi.org/10.7554/eLife.21356.001
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Affiliation(s)
- Robert F Levendosky
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, United States
| | - Anton Sabantsev
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Sebastian Deindl
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Gregory D Bowman
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, United States
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35
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Zhou W, Gao J, Ma J, Cao L, Zhang C, Zhu Y, Dong A, Shen WH. Distinct roles of the histone chaperones NAP1 and NRP and the chromatin-remodeling factor INO80 in somatic homologous recombination in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 88:397-410. [PMID: 27352805 DOI: 10.1111/tpj.13256] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 06/24/2016] [Indexed: 05/10/2023]
Abstract
Homologous recombination (HR) of nuclear DNA occurs within the context of a highly complex chromatin structure. Despite extensive studies of HR in diverse organisms, mechanisms regulating HR within the chromatin context remain poorly elucidated. Here we investigate the role and interplay of the histone chaperones NUCLEOSOME ASSEMBLY PROTEIN1 (NAP1) and NAP1-RELATED PROTEIN (NRP) and the ATP-dependent chromatin-remodeling factor INOSITOL AUXOTROPHY80 (INO80) in regulating somatic HR in Arabidopsis thaliana. We show that simultaneous knockout of the four AtNAP1 genes and the two NRP genes in the sextuple mutant m123456-1 barely affects normal plant growth and development. Interestingly, compared with the respective AtNAP1 (m123-1 and m1234-1) or NRP (m56-1) loss-of-function mutants, the sextuple mutant m123456-1 displays an enhanced plant hypersensitivity to UV or bleomycin treatments. Using HR reporter constructs, we show that AtNAP1 and NRP act in parallel to synergistically promote somatic HR. Distinctively, the AtINO80 loss-of-function mutation (atino80-5) is epistatic to m56-1 in plant phenotype and telomere length but hypostatic to m56-1 in HR determinacy. Further analyses show that expression of HR machinery genes and phosphorylation of H2A.X (γ-H2A.X) are not impaired in the mutants. Collectively, our study indicates that NRP and AtNAP1 synergistically promote HR upstream of AtINO80-mediated chromatin remodeling after the formation of γ-H2A.X foci during DNA damage repair.
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Affiliation(s)
- Wangbin Zhou
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
| | - Juan Gao
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
- Institut de Biologie Moléculaire des Plantes (IBMP), UPR2357 CNRS, Université de Strasbourg, 12 rue du Général Zimmer, Strasbourg Cédex, 67084, France
- School of Life Sciences, Shanghai Key Laboratory of Bio-Energy Crops, Shanghai University, Shanghai, 200444, China
| | - Jing Ma
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
| | - Lin Cao
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
| | - Chi Zhang
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
| | - Yan Zhu
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
| | - Aiwu Dong
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
| | - Wen-Hui Shen
- Department of Biochemistry, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, School of Life Sciences, Institute of Plant Biology, Fudan University, Shanghai, 20043, China
- Institut de Biologie Moléculaire des Plantes (IBMP), UPR2357 CNRS, Université de Strasbourg, 12 rue du Général Zimmer, Strasbourg Cédex, 67084, France
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36
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Coordinated Action of Nap1 and RSC in Disassembly of Tandem Nucleosomes. Mol Cell Biol 2016; 36:2262-71. [PMID: 27273866 DOI: 10.1128/mcb.00195-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/01/2016] [Indexed: 12/15/2022] Open
Abstract
The SWI/SNF and RSC family of ATP-dependent chromatin remodelers disassembles nucleosomes by moving nucleosomes into the vicinity of adjoining nucleosomes. We found that the histone chaperone Nap1 efficiently promotes disassembly of adjacent nucleosomes with which RSC collides and not the disassembly of nucleosomes mobilized by RSC. Nap1 is specific to RSC, as it does not target SWI/SNF, its paralog in Saccharomyces cerevisiae Extensive mutational analysis of Nap1 has revealed that Nap1 affinity for histones H2A-H2B and H3-H4 and its ability to displace histones from DNA are required for Nap1 to enhance RSC-mediated disassembly. Other histone chaperones, such as Vps75, that also bind histones are not able to enhance RSC-mediated disassembly. Our study suggests a mechanism by which Nap1 is recruited to actively transcribed regions and assists in the passage of the transcription complex through chromatin, and it provides a novel mechanism for the coordinated action of RSC and Nap1.
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37
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Aguilar-Gurrieri C, Larabi A, Vinayachandran V, Patel NA, Yen K, Reja R, Ebong IO, Schoehn G, Robinson CV, Pugh BF, Panne D. Structural evidence for Nap1-dependent H2A-H2B deposition and nucleosome assembly. EMBO J 2016; 35:1465-82. [PMID: 27225933 PMCID: PMC4931181 DOI: 10.15252/embj.201694105] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/21/2016] [Indexed: 11/25/2022] Open
Abstract
Nap1 is a histone chaperone involved in the nuclear import of H2A–H2B and nucleosome assembly. Here, we report the crystal structure of Nap1 bound to H2A–H2B together with in vitro and in vivo functional studies that elucidate the principles underlying Nap1‐mediated H2A–H2B chaperoning and nucleosome assembly. A Nap1 dimer provides an acidic binding surface and asymmetrically engages a single H2A–H2B heterodimer. Oligomerization of the Nap1–H2A–H2B complex results in burial of surfaces required for deposition of H2A–H2B into nucleosomes. Chromatin immunoprecipitation‐exonuclease (ChIP‐exo) analysis shows that Nap1 is required for H2A–H2B deposition across the genome. Mutants that interfere with Nap1 oligomerization exhibit severe nucleosome assembly defects showing that oligomerization is essential for the chaperone function. These findings establish the molecular basis for Nap1‐mediated H2A–H2B deposition and nucleosome assembly.
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Affiliation(s)
- Carmen Aguilar-Gurrieri
- European Molecular Biology Laboratory, Grenoble, France Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France
| | - Amédé Larabi
- European Molecular Biology Laboratory, Grenoble, France Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France
| | - Vinesh Vinayachandran
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
| | - Nisha A Patel
- Department of Chemistry, University of Oxford, Oxford, UK
| | - Kuangyu Yen
- Department of Cell Biology, Southern Medical University, Guangzhou, China
| | - Rohit Reja
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
| | - Ima-O Ebong
- Department of Chemistry, University of Oxford, Oxford, UK
| | - Guy Schoehn
- Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France Université Grenoble-Alpes, Grenoble, France Centre National de la Recherche Scientifique (CNRS) IBS, Grenoble, France CEA, IBS, Grenoble, France
| | | | - B Franklin Pugh
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
| | - Daniel Panne
- European Molecular Biology Laboratory, Grenoble, France Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France
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38
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Histone Chaperone Nap1 Is a Major Regulator of Histone H2A-H2B Dynamics at the Inducible GAL Locus. Mol Cell Biol 2016; 36:1287-96. [PMID: 26884462 DOI: 10.1128/mcb.00835-15] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 01/25/2016] [Indexed: 02/02/2023] Open
Abstract
Histone chaperones, like nucleosome assembly protein 1 (Nap1), play a critical role in the maintenance of chromatin architecture. Here, we use the GAL locus in Saccharomyces cerevisiae to investigate the influence of Nap1 on chromatin structure and histone dynamics during distinct transcriptional states. When the GAL locus is not expressed, cells lacking Nap1 show an accumulation of histone H2A-H2B but not histone H3-H4 at this locus. Excess H2A-H2B interacts with the linker DNA between nucleosomes, and the interaction is independent of the inherent DNA-binding affinity of H2A-H2B for these particular sequences as measured in vitro When the GAL locus is transcribed, excess H2A-H2B is reversed, and levels of all chromatin-bound histones are depleted in cells lacking Nap1. We developed an in vivo system to measure histone exchange at the GAL locus and observed considerable variability in the rate of exchange across the locus in wild-type cells. We recapitulate this variability with in vitro nucleosome reconstitutions, which suggests a contribution of DNA sequence to histone dynamics. We also find that Nap1 is required for transcription-dependent H2A-H2B exchange. Altogether, these results indicate that Nap1 is essential for maintaining proper chromatin composition and modulating the exchange of H2A-H2B in vivo.
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39
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Wenderski W, Maze I. Histone turnover and chromatin accessibility: Critical mediators of neurological development, plasticity, and disease. Bioessays 2016; 38:410-9. [PMID: 26990528 DOI: 10.1002/bies.201500171] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In postmitotic neurons, nucleosomal turnover was long considered to be a static process that is inconsequential to transcription. However, our recent studies in human and rodent brain indicate that replication-independent (RI) nucleosomal turnover, which requires the histone variant H3.3, is dynamic throughout life and is necessary for activity-dependent gene expression, synaptic connectivity, and cognition. H3.3 turnover also facilitates cellular lineage specification and plays a role in suppressing the expression of heterochromatic repetitive elements, including mutagenic transposable sequences, in mouse embryonic stem cells. In this essay, we review mechanisms and functions for RI nucleosomal turnover in brain and present the hypothesis that defects in histone dynamics may represent a common mechanism underlying neurological aging and disease.
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Affiliation(s)
- Wendy Wenderski
- Department of Developmental Biology, Stanford University, Stanford, CA, USA
| | - Ian Maze
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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40
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Abstract
In this issue of Molecular Cell, Kubik et al. (2015) describe how the RSC chromatin remodeling complex collaborates with two DNA sequence motifs and sequence-specific general regulatory factors to assemble fragile nucleosomes at highly transcribed yeast Pol II promoters, and they distinguish these from promoters bearing stable nucleosomes.
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Affiliation(s)
- Suman K Pradhan
- Department of Biological Chemistry, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Yong Xue
- Department of Biological Chemistry, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Michael F Carey
- Department of Biological Chemistry, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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41
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Zhou W, Zhu Y, Dong A, Shen WH. Histone H2A/H2B chaperones: from molecules to chromatin-based functions in plant growth and development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 83:78-95. [PMID: 25781491 DOI: 10.1111/tpj.12830] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Revised: 03/10/2015] [Accepted: 03/11/2015] [Indexed: 05/06/2023]
Abstract
Nucleosomal core histones (H2A, H2B, H3 and H4) must be assembled, replaced or exchanged to preserve or modify chromatin organization and function according to cellular needs. Histone chaperones escort histones, and play key functions during nucleosome assembly/disassembly and in nucleosome structure configuration. Because of their location at the periphery of nucleosome, histone H2A-H2B dimers are remarkably dynamic. Here we focus on plant histone H2A/H2B chaperones, particularly members of the NUCLEOSOME ASSEMBLY PROTEIN-1 (NAP1) and FACILITATES CHROMATIN TRANSCRIPTION (FACT) families, discussing their molecular features, properties, regulation and function. Covalent histone modifications (e.g. ubiquitination, phosphorylation, methylation, acetylation) and H2A variants (H2A.Z, H2A.X and H2A.W) are also discussed in view of their crucial importance in modulating nucleosome organization and function. We further discuss roles of NAP1 and FACT in chromatin-based processes, such as transcription, DNA replication and repair. Specific functions of NAP1 and FACT are evident when their roles are considered with respect to regulation of plant growth and development and in plant responses to environmental stresses. Future major challenges remain in order to define in more detail the overlapping and specific roles of various members of the NAP1 family as well as differences and similarities between NAP1 and FACT family members, and to identify and characterize their partners as well as new families of chaperones to understand histone variant incorporation and chromatin target specificity.
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Affiliation(s)
- Wangbin Zhou
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Department of Biochemistry, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, 20043, China
| | - Yan Zhu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Department of Biochemistry, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, 20043, China
| | - Aiwu Dong
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Department of Biochemistry, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, 20043, China
| | - Wen-Hui Shen
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Department of Biochemistry, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, 20043, China
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Université de Strasbourg, 12 rue du Général Zimmer, 67084, Strasbourg, France
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42
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Xue Y, Van C, Pradhan SK, Su T, Gehrke J, Kuryan BG, Kitada T, Vashisht A, Tran N, Wohlschlegel J, Peterson CL, Kurdistani SK, Carey MF. The Ino80 complex prevents invasion of euchromatin into silent chromatin. Genes Dev 2015; 29:350-5. [PMID: 25691465 PMCID: PMC4335291 DOI: 10.1101/gad.256255.114] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Here we show that the Ino80 chromatin remodeling complex (Ino80C) directly prevents euchromatin from invading transcriptionally silent chromatin within intergenic regions and at the border of euchromatin and heterochromatin. Deletion of Ino80C subunits leads to increased H3K79 methylation and noncoding RNA polymerase II (Pol II) transcription centered at the Ino80C-binding sites. The effect of Ino80C is direct, as it blocks H3K79 methylation by Dot1 in vitro. Heterochromatin stimulates the binding of Ino80C in vitro and in vivo. Our data reveal that Ino80C serves as a general silencing complex that restricts transcription to gene units in euchromatin.
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Affiliation(s)
- Yong Xue
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Christopher Van
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Suman K Pradhan
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Trent Su
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Jason Gehrke
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Benjamin G Kuryan
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Tasuku Kitada
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Ajay Vashisht
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Nancy Tran
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - James Wohlschlegel
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Craig L Peterson
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Siavash K Kurdistani
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Michael F Carey
- Department of Biological Chemistry, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095, USA;
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43
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Bowman GD, Poirier MG. Post-translational modifications of histones that influence nucleosome dynamics. Chem Rev 2015; 115:2274-95. [PMID: 25424540 PMCID: PMC4375056 DOI: 10.1021/cr500350x] [Citation(s) in RCA: 319] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Indexed: 12/12/2022]
Affiliation(s)
- Gregory D. Bowman
- T.
C. Jenkins Department of Biophysics, Johns
Hopkins University, Baltimore, Maryland 21218, United States
| | - Michael G. Poirier
- Department of Physics, and Department of
Chemistry and Biochemistry, The Ohio State
University, Columbus, Ohio 43210, United
States
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44
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Histone exchange, chromatin structure and the regulation of transcription. Nat Rev Mol Cell Biol 2015; 16:178-89. [DOI: 10.1038/nrm3941] [Citation(s) in RCA: 650] [Impact Index Per Article: 72.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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45
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Casanova M, de Monbrison F, van Dijk J, Janke C, Pagès M, Bastien P. Characterisation of polyglutamylases in trypanosomatids. Int J Parasitol 2014; 45:121-32. [PMID: 25444861 DOI: 10.1016/j.ijpara.2014.09.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/16/2014] [Accepted: 09/17/2014] [Indexed: 11/30/2022]
Abstract
Microtubules are subject to post-translational modifications, which are thought to have crucial roles in the function of complex microtubule-based organelles. Among these, polyglutamylation was relatively recently discovered, and was related to centrosome stability, axonemal maintenance and mobility, and neurite outgrowth. In trypanosomatids, parasitic protozoa where microtubules constitute the essential component of the cytoskeleton, the function of polyglutamylated microtubules is unknown. Here, in order to better understand the role of this conserved but highly divergent post-translational modification, we characterised glutamylation and putative polyglutamylases in these parasites. We showed that microtubules are intensely glutamylated in all stages of the cell cycle, including interphase. Moreover, a cell cycle-dependent gradient of glutamylation was observed along the cell anteroposterior axis, which might be related to active growth of the microtubule 'corset' during the cell cycle. We also identified two putative polyglutamylase proteins (among seven analysed here) which appeared to be clearly and directly involved in microtubule polyglutamylation in in vitro activity assays. Paradoxically, in view of the importance of tubulins and of their extensive glutamylation in these organisms, RNA interference-based knockdown of all these proteins had no effect on cell growth, suggesting either functional redundancy or, more likely, subtle roles such as function modulation or interaction with protein partners.
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Affiliation(s)
- Magali Casanova
- Centre National de la Recherche Scientifique (CNRS), 5290-IRD 224-University Montpellier 1, Research Unit "MIVEGEC", Montpellier, France
| | - Frédérique de Monbrison
- Centre National de la Recherche Scientifique (CNRS), 5290-IRD 224-University Montpellier 1, Research Unit "MIVEGEC", Montpellier, France
| | - Juliette van Dijk
- CNRS UMR 5237 - University Montpellier 2 and 1, Research Unit "Centre de Recherche de Biochimie Macromoléculaire", Montpellier, France
| | - Carsten Janke
- CNRS UMR 5237 - University Montpellier 2 and 1, Research Unit "Centre de Recherche de Biochimie Macromoléculaire", Montpellier, France
| | - Michel Pagès
- Centre National de la Recherche Scientifique (CNRS), 5290-IRD 224-University Montpellier 1, Research Unit "MIVEGEC", Montpellier, France
| | - Patrick Bastien
- Centre National de la Recherche Scientifique (CNRS), 5290-IRD 224-University Montpellier 1, Research Unit "MIVEGEC", Montpellier, France; CHU (Hospital University Centre) of Montpellier and University Montpellier 1 (Faculty of Medicine), Laboratoire de Parasitologie-Mycologie, Montpellier, France.
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46
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Spain MM, Ansari SA, Pathak R, Palumbo MJ, Morse RH, Govind CK. The RSC complex localizes to coding sequences to regulate Pol II and histone occupancy. Mol Cell 2014; 56:653-66. [PMID: 25457164 DOI: 10.1016/j.molcel.2014.10.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 09/26/2014] [Accepted: 10/02/2014] [Indexed: 10/24/2022]
Abstract
ATP-dependent chromatin remodelers regulate chromatin structure during multiple stages of transcription. We report that RSC, an essential chromatin remodeler, is recruited to the open reading frames (ORFs) of actively transcribed genes genome wide, suggesting a role for RSC in regulating transcription elongation. Consistent with such a role, Pol II occupancy in the ORFs of weakly transcribed genes is drastically reduced upon depletion of the RSC catalytic subunit Sth1. RSC inactivation also reduced histone H3 occupancy across transcribed regions. Remarkably, the strongest effects on Pol II and H3 occupancy were confined to the genes displaying the greatest RSC ORF enrichment. Additionally, RSC recruitment to the ORF requires the activities of the SAGA and NuA4 HAT complexes and is aided by the activities of the Pol II CTD Ser2 kinases Bur1 and Ctk1. Overall, our findings strongly implicate ORF-associated RSC in governing Pol II function and in maintaining chromatin structure over transcribed regions.
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Affiliation(s)
- Marla M Spain
- Department of Biological Sciences, Oakland University, Rochester, MI 48309, USA
| | - Suraiya A Ansari
- Laboratory of Molecular Genetics, Wadsworth Center, NY State Department of Health, Albany, NY 12208, USA
| | - Rakesh Pathak
- Department of Biological Sciences, Oakland University, Rochester, MI 48309, USA
| | - Michael J Palumbo
- Laboratory of Molecular Genetics, Wadsworth Center, NY State Department of Health, Albany, NY 12208, USA
| | - Randall H Morse
- Laboratory of Molecular Genetics, Wadsworth Center, NY State Department of Health, Albany, NY 12208, USA
| | - Chhabi K Govind
- Department of Biological Sciences, Oakland University, Rochester, MI 48309, USA.
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47
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Mirón-García MC, Garrido-Godino AI, Martínez-Fernández V, Fernández-Pevida A, Cuevas-Bermúdez A, Martín-Expósito M, Chávez S, de la Cruz J, Navarro F. The yeast prefoldin-like URI-orthologue Bud27 associates with the RSC nucleosome remodeler and modulates transcription. Nucleic Acids Res 2014; 42:9666-76. [PMID: 25081216 PMCID: PMC4150788 DOI: 10.1093/nar/gku685] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Bud27, the yeast orthologue of human URI/RMP, is a member of the prefoldin-like family of ATP-independent molecular chaperones. It has recently been shown to mediate the assembly of the three RNA polymerases in an Rpb5-dependent manner. In this work, we present evidence of Bud27 modulating RNA pol II transcription elongation. We show that Bud27 associates with RNA pol II phosphorylated forms (CTD-Ser5P and CTD-Ser2P), and that its absence affects RNA pol II occupancy of transcribed genes. We also reveal that Bud27 associates in vivo with the Sth1 component of the chromatin remodeling complex RSC and mediates its association with RNA pol II. Our data suggest that Bud27, in addition of contributing to Rpb5 folding within the RNA polymerases, also participates in the correct assembly of other chromatin-associated protein complexes, such as RSC, thereby modulating their activity.
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Affiliation(s)
- María Carmen Mirón-García
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Paraje de las Lagunillas, s/n, 23071, Jaén, Spain
| | - Ana Isabel Garrido-Godino
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Paraje de las Lagunillas, s/n, 23071, Jaén, Spain
| | - Verónica Martínez-Fernández
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Paraje de las Lagunillas, s/n, 23071, Jaén, Spain
| | - Antonio Fernández-Pevida
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, E-41013 Sevilla, Spain Departamento de Genética, Universidad de Sevilla, E41012 Sevilla, Spain
| | - Abel Cuevas-Bermúdez
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Paraje de las Lagunillas, s/n, 23071, Jaén, Spain
| | - Manuel Martín-Expósito
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Paraje de las Lagunillas, s/n, 23071, Jaén, Spain
| | - Sebastián Chávez
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, E-41013 Sevilla, Spain Departamento de Genética, Universidad de Sevilla, E41012 Sevilla, Spain
| | - Jesús de la Cruz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, E-41013 Sevilla, Spain Departamento de Genética, Universidad de Sevilla, E41012 Sevilla, Spain
| | - Francisco Navarro
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Paraje de las Lagunillas, s/n, 23071, Jaén, Spain
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48
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Duttke SHC. RNA polymerase III accurately initiates transcription from RNA polymerase II promoters in vitro. J Biol Chem 2014; 289:20396-404. [PMID: 24917680 DOI: 10.1074/jbc.m114.563254] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In eukaryotes, there are three major RNA polymerases (Pol) in the nucleus, which are commonly described as transcribing non-overlapping subsets of genes. Structural studies have highlighted a conserved core shared among all three transcription systems. Initiation of human Pol III from TATA box-containing Pol II promoters under conditions with impaired Pol II transcription activity have been described previously. RNA polymerase III and Pol II were found to co-localize at the promoters of the c-myc gene and the RPPH1 sRNA in vivo. Here, I report that Pol III can, like Pol II, initiate transcription from most tested Pol II core promoters when assayed with crude human nuclear extracts (HSK, SNF, or Dignam). Both polymerases often initiate from the same transcription start site, and depend on a TATA box or AT-rich region but not the downstream promoter element (DPE) or the motif ten element (MTE). Moderate (∼2-fold) changes in the ratio of DNA template to nuclear extract were sufficient to change Pol II-mediated transcription to a mixture of Pol II- and Pol III-, or to a solely Pol III-dependent initiation of transcription from Pol II promoters. Polymerase specificity is thus not fixed but a variable that depends on the properties of the promoter and the transcription conditions. These findings provide functional evidence for a close similarity between the Pol II and Pol III transcription complexes, and additionally explain previous controversies in the literature.
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Affiliation(s)
- Sascha H C Duttke
- From the Section of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093
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49
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Prescott TAK, Rigby LP, Veitch NC, Simmonds MSJ. The haploinsufficiency profile of α-hederin suggests a caspofungin-like antifungal mode of action. PHYTOCHEMISTRY 2014; 101:116-120. [PMID: 24569176 DOI: 10.1016/j.phytochem.2014.01.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 01/28/2014] [Accepted: 01/31/2014] [Indexed: 06/03/2023]
Abstract
The leaves of common ivy (Hedera helix) contain the cytotoxic saponin α-hederin, which is inhibitory to Candida albicans at low concentrations. To investigate the mode of action of α-hederin, a haploinsufficiency screen was carried out using a library of 1152 Saccharomyces cerevisiae deletion strains. An ethanol ivy extract containing α-hederin was used in the initial screen to reduce the amount of compound required. Strains exhibiting disproportionately low growth were then examined in more detail by comparing growth curves in the presence and absence of α-hederin. This approach identified three hypersensitive strains carrying gene deletions for components of the transcription related proteins SWI/SNF, RNA polymerase II and the RSC complex. Saponin cytotoxicity is often attributed to membrane damage, however α-hederin did not induce hypersensitivity with an aminophospholipid translocase deletion strain that is frequently hypersensitive to membrane damaging agents. The haploinsufficiency profile of α-hederin is most similar to that reported for drugs such as caspofungin that inhibit synthesis of the fungal cell wall. Screening with plant extracts rather than isolated compounds, provides a valuable shortcut in haploinsufficiency screening provided hypersensitive strains are then confirmed as such using purified active principles.
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Affiliation(s)
| | - Luke P Rigby
- Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK
| | - Nigel C Veitch
- Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK
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50
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Bowman A, Hammond CM, Stirling A, Ward R, Shang W, El-Mkami H, Robinson DA, Svergun DI, Norman DG, Owen-Hughes T. The histone chaperones Vps75 and Nap1 form ring-like, tetrameric structures in solution. Nucleic Acids Res 2014; 42:6038-51. [PMID: 24688059 PMCID: PMC4027167 DOI: 10.1093/nar/gku232] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
NAP-1 fold histone chaperones play an important role in escorting histones to and from sites of nucleosome assembly and disassembly. The two NAP-1 fold histone chaperones in budding yeast, Vps75 and Nap1, have previously been crystalized in a characteristic homodimeric conformation. In this study, a combination of small angle X-ray scattering, multi angle light scattering and pulsed electron–electron double resonance approaches were used to show that both Vps75 and Nap1 adopt ring-shaped tetrameric conformations in solution. This suggests that the formation of homotetramers is a common feature of NAP-1 fold histone chaperones. The tetramerisation of NAP-1 fold histone chaperones may act to shield acidic surfaces in the absence of histone cargo thus providing a ‘self-chaperoning’ type mechanism.
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Affiliation(s)
- Andrew Bowman
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, DD1 5EH, UK
| | - Colin M Hammond
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, DD1 5EH, UK
| | - Andrew Stirling
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, DD1 5EH, UK
| | - Richard Ward
- Nucleic Acids Structure Research Group, University of Dundee, Dundee, DD1 5EH, UK
| | - Weifeng Shang
- European Molecular Biology Laboratory, Hamburg Outstation, c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany
| | - Hassane El-Mkami
- School of Physics and Astronomy, University of St Andrews, St Andrews FE2 4KM, UK
| | - David A Robinson
- Division of Biological Chemistry and Drug Discovery, University of Dundee, Dundee, DD1 5EH, UK
| | - Dmitri I Svergun
- European Molecular Biology Laboratory, Hamburg Outstation, c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany
| | - David G Norman
- Nucleic Acids Structure Research Group, University of Dundee, Dundee, DD1 5EH, UK
| | - Tom Owen-Hughes
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, DD1 5EH, UK
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