151
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Winogradoff D, Aksimentiev A. Molecular Mechanism of Spontaneous Nucleosome Unraveling. J Mol Biol 2019; 431:323-335. [PMID: 30468737 PMCID: PMC6331254 DOI: 10.1016/j.jmb.2018.11.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 10/26/2018] [Accepted: 11/12/2018] [Indexed: 11/18/2022]
Abstract
Meters of DNA wrap around histone proteins to form nucleosomes and fit inside the micron-diameter nucleus. For the genetic information encoded in the DNA to become available for transcription, replication, and repair, the DNA-histone assembly must be disrupted. Experiment has indicated that the outer stretches of nucleosomal DNA "breathe" by spontaneously detaching from and reattaching to the histone core. Here, we report direct observation of spontaneous DNA breathing in atomistic molecular dynamics simulations, detailing a microscopic mechanism of the DNA breathing process. According to our simulations, the outer stretches of nucleosomal DNA detach in discrete steps involving 5 or 10 base pairs, with the detachment process being orchestrated by the motion of several conserved histone residues. The inner stretches of nucleosomal DNA are found to be more stably associated with the histone core by more abundant nonspecific DNA-protein contacts, providing a microscopic interpretation of nucleosome unraveling experiments. The CG content of nucleosomal DNA is found to anticorrelate with the extent of unwrapping, supporting the possibility that AT-rich segments may signal the start of transcription by forming less stable nucleosomes.
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Affiliation(s)
- David Winogradoff
- Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Aleksei Aksimentiev
- Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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152
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Farnung L, Vos SM, Cramer P. Structure of transcribing RNA polymerase II-nucleosome complex. Nat Commun 2018; 9:5432. [PMID: 30575770 PMCID: PMC6303367 DOI: 10.1038/s41467-018-07870-y] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 12/05/2018] [Indexed: 01/08/2023] Open
Abstract
Transcription of eukaryotic protein-coding genes requires passage of RNA polymerase II (Pol II) through nucleosomes, but it is unclear how this is achieved. Here we report the cryo-EM structure of transcribing Saccharomyces cerevisiae Pol II engaged with a downstream nucleosome core particle at an overall resolution of 4.4 Å. Pol II and the nucleosome are observed in a defined relative orientation that is not predicted. Pol II contacts both sides of the nucleosome dyad using its clamp head and lobe domains. Structural comparisons reveal that the elongation factors TFIIS, DSIF, NELF, SPT6, and PAF1 complex can be accommodated on the Pol II surface in the presence of the oriented nucleosome. Our results provide a starting point for analysing the mechanisms of chromatin transcription. Eukaryotic transcription requires passage of RNA polymerase II (Pol II) through chromatin, which is impaired by nucleosomes. Here the authors report the cryo-EM structure of transcribing Pol II engaged with a downstream nucleosome core particle at an overall resolution of 4.4 Å, providing insights into the mechanism of chromatin transcription.
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Affiliation(s)
- Lucas Farnung
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077, Göttingen, Germany
| | - Seychelle M Vos
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077, Göttingen, Germany
| | - Patrick Cramer
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077, Göttingen, Germany.
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153
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Huang YC, Su CJ, Korolev N, Berezhnoy NV, Wang S, Soman A, Chen CY, Chen HL, Jeng US, Nordenskiöld L. The effect of linker DNA on the structure and interaction of nucleosome core particles. SOFT MATTER 2018; 14:9096-9106. [PMID: 30215440 DOI: 10.1039/c8sm00998h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In eukaryotes, the compaction of chromatin fibers composed of nucleosome core particles (NCPs) connected by a linker DNA into chromosomes is highly efficient; however, the underlying folding mechanisms remain elusive. We used small angle X-ray scattering (SAXS) to investigate the influence of linker DNA length on the local structure and the interparticle interactions of the NCPs. In the presence of the linker DNA of 30 bp or less in length, the results suggest partial unwrapping of nucleosomal DNA on the NCP irrespective of the linker DNA length. Moreover, the presence of 15 bp linker DNA alleviated the electrostatic repulsion between the NCPs and prevented the formation of an ordered columnar hexagonal phase, demonstrating that the linker DNA plays an active role in chromatin folding.
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Affiliation(s)
- Yen-Chih Huang
- Department of Chemical Engineering and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsin-Chu 30013, Taiwan.
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154
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Bai J, Zhang Y, Xi Z, Greenberg MM, Zhou C. Oxidation of 8-Oxo-7,8-dihydro-2'-deoxyguanosine Leads to Substantial DNA-Histone Cross-Links within Nucleosome Core Particles. Chem Res Toxicol 2018; 31:1364-1372. [PMID: 30412392 DOI: 10.1021/acs.chemrestox.8b00244] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
8-Oxo-7,8-dihydro-2'-deoxyguanosine(8-oxodGuo) is a common primary product of cellular oxidative DNA damage. 8-OxodGuo is more readily oxidized than 2'-deoxyguanosine (dG); a two-electron oxidation generates a highly reactive intermediate (OGox), which forms covalent adducts with nucleophiles, including OH-, free amines, and the side chains of amino acids such as lysine. We determined here that K3Fe(CN)6 oxidation of 8-oxodGuo in nucleosome core particles (NCPs) produces high yields, quantitative (i.e., 100%) in some cases, of DNA-protein cross-links (DPCs). The efficiency of DPC formation was closely related to 8-oxodGuo base pairing and location within the NCP and was only slightly decreased by adding the DNA-protective polyamine spermine to the system. Using NCPs that contained histone mutants, we determined that DPCs result predominantly from OGox trapping by the N-terminal histone amine. The DPCs were stable under physiological conditions and therefore could have important biological consequences. For instance, the essentially quantitative yield of DPCs at some positions within NCPs would reduce the yield of the mutagenic DNA lesions spiroiminodihydantoin and guanidinohydantoin produced from the common intermediate OGox, which in turn would affect mutation signatures of oxidative stress in a position-dependent manner. In summary, our findings indicate that site-specific incorporation of 8-oxodGuo into NCPs, followed by its oxidation, leads to DPCs with an efficiency depending on 8-oxodGuo location and orientation. Given that 8-oxodGuo formation is widespread in genomic DNA and that DPC formation is highly efficient, DPCs may occur in eukaryotic cells and may affect several important biological processes.
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Affiliation(s)
- Jing Bai
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Yingqian Zhang
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Zhen Xi
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Marc M Greenberg
- Department of Chemistry , Johns Hopkins University , 3400 N. Charles Street , Baltimore , Maryland 21218 , United States
| | - Chuanzheng Zhou
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry , Nankai University , Tianjin 300071 , China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300071 , China
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155
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Histone tails decrease N7-methyl-2'-deoxyguanosine depurination and yield DNA-protein cross-links in nucleosome core particles and cells. Proc Natl Acad Sci U S A 2018; 115:E11212-E11220. [PMID: 30429328 DOI: 10.1073/pnas.1813338115] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Monofunctional alkylating agents preferentially react at the N7 position of 2'-deoxyguanosine in duplex DNA. Methylated DNA, such as that produced by methyl methanesulfonate (MMS) and temozolomide, exists for days in organisms. The predominant consequence of N7-methyl-2'-deoxyguanosine (MdG) is widely believed to be abasic site (AP) formation via hydrolysis, a process that is slow in free DNA. Examination of MdG reactivity within nucleosome core particles (NCPs) provided two general observations. MdG depurination rate constants are reduced in NCPs compared with when the identical DNA sequence is free in solution. The magnitude of the decrease correlates with proximity to the positively charged histone tails, and experiments in NCPs containing histone variants reveal that positively charged amino acids are responsible for the decreased rate of abasic site formation from MdG. In addition, the lysine-rich histone tails form DNA-protein cross-links (DPCs) with MdG. Cross-link formation is reversible and is ascribed to nucleophilic attack at the C8 position of MdG. DPC and retarded abasic site formation are observed in NCPs randomly damaged by MMS, indicating that these are general processes. Histone-MdG cross-links were also detected by mass spectrometry in chromatin isolated from V79 Chinese hamster lung cells treated with MMS. The formation of DPCs following damage by a monofunctional alkylating agent has not been reported previously. These observations reveal the possibility that such DPCs may contribute to the cytotoxicity of monofunctional alkylating agents, such as MMS, N-methyl-N-nitrosourea, and temozolomide.
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156
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High precision FRET studies reveal reversible transitions in nucleosomes between microseconds and minutes. Nat Commun 2018; 9:4628. [PMID: 30401903 PMCID: PMC6219519 DOI: 10.1038/s41467-018-06758-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 09/17/2018] [Indexed: 11/08/2022] Open
Abstract
Nucleosomes play a dual role in compacting the genome and regulating the access to DNA. To unravel the underlying mechanism, we study fluorescently labeled mononucleosomes by multi-parameter FRET measurements and characterize their structural and dynamic heterogeneity upon NaCl-induced destabilization. Species-selective fluorescence lifetime analysis and dynamic photon distribution analysis reveal intermediates during nucleosome opening and lead to a coherent structural and kinetic model. In dynamic octasomes and hexasomes the interface between the H2A-H2B dimers and the (H3-H4)2 tetramer opens asymmetrically by an angle of ≈20° on a 50 and 15 µs time scale, respectively. This is followed by a slower stepwise release of the dimers coupled with DNA unwrapping. A mutation (H2A-R81A) at the interface between H2A and H3 facilitates initial opening, confirming the central role of the dimer:tetramer interface for nucleosome stability. Partially opened states such as those described here might serve as convenient nucleation sites for DNA-recognizing proteins.
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157
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Brandani GB, Takada S. Chromatin remodelers couple inchworm motion with twist-defect formation to slide nucleosomal DNA. PLoS Comput Biol 2018; 14:e1006512. [PMID: 30395604 PMCID: PMC6237416 DOI: 10.1371/journal.pcbi.1006512] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 11/15/2018] [Accepted: 09/13/2018] [Indexed: 01/25/2023] Open
Abstract
ATP-dependent chromatin remodelers are molecular machines that control genome organization by repositioning, ejecting, or editing nucleosomes, activities that confer them essential regulatory roles on gene expression and DNA replication. Here, we investigate the molecular mechanism of active nucleosome sliding by means of molecular dynamics simulations of the Snf2 remodeler translocase in complex with a nucleosome. During its inchworm motion driven by ATP consumption, the translocase overwrites the original nucleosome energy landscape via steric and electrostatic interactions to induce sliding of nucleosomal DNA unidirectionally. The sliding is initiated at the remodeler binding location via the generation of a pair of twist defects, which then spontaneously propagate to complete sliding throughout the entire nucleosome. We also reveal how remodeler mutations and DNA sequence control active nucleosome repositioning, explaining several past experimental observations. These results offer a detailed mechanistic picture of remodeling important for the complete understanding of these key biological processes. Nucleosomes are the protein-DNA complexes underlying Eukaryotic genome organization, and serve as regulators of gene expression by occluding DNA to other proteins. This regulation requires the precise positioning of nucleosomes along DNA. Chromatin remodelers are the molecular machines that consume ATP to slide nucleosome at their correct locations, but the mechanisms of remodeling are still unclear. Based on the static structural information of a remodeler bound on nucleosome, we performed molecular dynamics computer simulations revealing the details of how remodelers slide nucleosomal DNA: the inchworm-like motion of remodelers create small DNA deformations called twist defects, which then spontaneously propagate throughout the nucleosome to induce sliding. These simulations explain several past experimental findings and are important for our understanding of genome organization.
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Affiliation(s)
- Giovanni B. Brandani
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Shoji Takada
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
- * E-mail:
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158
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Garcia-Saez I, Menoni H, Boopathi R, Shukla MS, Soueidan L, Noirclerc-Savoye M, Le Roy A, Skoufias DA, Bednar J, Hamiche A, Angelov D, Petosa C, Dimitrov S. Structure of an H1-Bound 6-Nucleosome Array Reveals an Untwisted Two-Start Chromatin Fiber Conformation. Mol Cell 2018; 72:902-915.e7. [PMID: 30392928 DOI: 10.1016/j.molcel.2018.09.027] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 07/27/2018] [Accepted: 09/20/2018] [Indexed: 12/13/2022]
Abstract
Chromatin adopts a diversity of regular and irregular fiber structures in vitro and in vivo. However, how an array of nucleosomes folds into and switches between different fiber conformations is poorly understood. We report the 9.7 Å resolution crystal structure of a 6-nucleosome array bound to linker histone H1 determined under ionic conditions that favor incomplete chromatin condensation. The structure reveals a flat two-start helix with uniform nucleosomal stacking interfaces and a nucleosome packing density that is only half that of a twisted 30-nm fiber. Hydroxyl radical footprinting indicates that H1 binds the array in an on-dyad configuration resembling that observed for mononucleosomes. Biophysical, cryo-EM, and crosslinking data validate the crystal structure and reveal that a minor change in ionic environment shifts the conformational landscape to a more compact, twisted form. These findings provide insights into the structural plasticity of chromatin and suggest a possible assembly pathway for a 30-nm fiber.
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Affiliation(s)
- Isabel Garcia-Saez
- Université Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France
| | - Hervé Menoni
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé - Allée des Alpes, 38700 La Tronche, France; Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS, Laboratoire de Biologie et de Modélisation de la Cellule LBMC, 46 Allée d'Italie, 69007 Lyon, France
| | - Ramachandran Boopathi
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé - Allée des Alpes, 38700 La Tronche, France; Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS, Laboratoire de Biologie et de Modélisation de la Cellule LBMC, 46 Allée d'Italie, 69007 Lyon, France
| | - Manu S Shukla
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé - Allée des Alpes, 38700 La Tronche, France; Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS, Laboratoire de Biologie et de Modélisation de la Cellule LBMC, 46 Allée d'Italie, 69007 Lyon, France
| | - Lama Soueidan
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé - Allée des Alpes, 38700 La Tronche, France; Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS, Laboratoire de Biologie et de Modélisation de la Cellule LBMC, 46 Allée d'Italie, 69007 Lyon, France
| | | | - Aline Le Roy
- Université Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France
| | - Dimitrios A Skoufias
- Université Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France
| | - Jan Bednar
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé - Allée des Alpes, 38700 La Tronche, France; Laboratory of the Biology and Pathology of the Eye, Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, Albertov 4, 128 00 Prague 2, Czech Republic.
| | - Ali Hamiche
- Département de Génomique Fonctionnelle et Cancer, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS, INSERM, 67404 Illkirch Cedex, France.
| | - Dimitar Angelov
- Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS, Laboratoire de Biologie et de Modélisation de la Cellule LBMC, 46 Allée d'Italie, 69007 Lyon, France.
| | - Carlo Petosa
- Université Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France.
| | - Stefan Dimitrov
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé - Allée des Alpes, 38700 La Tronche, France; "Roumen Tsanev" Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
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159
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Kujirai T, Ehara H, Fujino Y, Shirouzu M, Sekine SI, Kurumizaka H. Structural basis of the nucleosome transition during RNA polymerase II passage. Science 2018; 362:595-598. [PMID: 30287617 DOI: 10.1126/science.aau9904] [Citation(s) in RCA: 123] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 09/19/2018] [Indexed: 12/28/2022]
Abstract
Genomic DNA forms chromatin, in which the nucleosome is the repeating unit. The mechanism by which RNA polymerase II (RNAPII) transcribes the nucleosomal DNA remains unclear. Here we report the cryo-electron microscopy structures of RNAPII-nucleosome complexes in which RNAPII pauses at the superhelical locations SHL(-6), SHL(-5), SHL(-2), and SHL(-1) of the nucleosome. RNAPII pauses at the major histone-DNA contact sites, and the nucleosome interactions with the RNAPII subunits stabilize the pause. These structures reveal snapshots of nucleosomal transcription, in which RNAPII gradually tears DNA from the histone surface while preserving the histone octamer. The nucleosomes in the SHL(-1) complexes are bound to a "foreign" DNA segment, which might explain the histone transfer mechanism. These results provide the foundations for understanding chromatin transcription and epigenetic regulation.
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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.,RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Haruhiko Ehara
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Yuka Fujino
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.,Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Mikako Shirouzu
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Shun-Ichi Sekine
- 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. .,RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.,Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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160
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Krajewski WA. Effects of DNA Superhelical Stress on the Stability of H2B-Ubiquitylated Nucleosomes. J Mol Biol 2018; 430:5002-5014. [PMID: 30267746 DOI: 10.1016/j.jmb.2018.09.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/27/2018] [Accepted: 09/21/2018] [Indexed: 01/31/2023]
Abstract
On the nucleosome level, histone posttranslational modifications function mainly as the regulatory signals; in addition, some posttranslational modifications can enhance nucleosome stochastic folding, which is restricted in "canonic" nucleosomes. Recently, it has been shown in vitro that symmetric or asymmetric nucleosome ubiquitylation at H2BK34 (and H2BK120, to a lesser extent) can destabilize one of the nucleosomal H2A-H2B dimers and promote nucleosome conversion to a hexasome particle [Krajewski et al. (2018). Nucleic Acids Res., 46, 7631-7642]. Such lability of H2Bub nucleosomes raises a question of whether they could accommodate transient changes in DNA torsional tensions, which are generated by virtually any process that manipulates DNA strands. Using positively or negatively supercoiled DNA minicircles and homogeneously-modified H2Bub histones, we have found that DNA topology could strongly and selectively affect nucleosome stability depending on its ubiquitylation state (here the term "nucleosome stability" means the nucleosome property to maintain its structural integrity and dynamics characteristic to "canonic" nucleosomes). The results point to a role for H2B ubiquitylation in amplifying or mitigating the effects of a DNA torque on the nucleosome stability and dynamics.
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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.
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161
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Tarantino ME, Dow BJ, Drohat AC, Delaney S. Nucleosomes and the three glycosylases: High, medium, and low levels of excision by the uracil DNA glycosylase superfamily. DNA Repair (Amst) 2018; 72:56-63. [PMID: 30268365 DOI: 10.1016/j.dnarep.2018.09.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 09/16/2018] [Accepted: 09/17/2018] [Indexed: 01/19/2023]
Abstract
Human cells express the UDG superfamily of glycosylases, which excise uracil (U) from the genome. The three members of this structural superfamily are uracil DNA glycosylase (UNG/UDG), single-strand selective monofunctional uracil DNA glycosylase (SMUG1), and thymine DNA glycosylase (TDG). We previously reported that UDG is efficient at removing U from DNA packaged into nucleosome core particles (NCP) and is minimally affected by the histone proteins when acting on an outward-facing U in the dyad region. In an effort to determine whether this high activity is a general property of the UDG superfamily of glycosylases, we compare the activity of UDG, SMUG1, and TDG on a U:G wobble base pair using NCP assembled from Xenopus laevis histones and the Widom 601 positioning sequence. We found that while UDG is highly active, SMUG1 is severely inhibited on NCP and this inhibition is independent of sequence context. Here we also provide the first report of TDG activity on an NCP, and found that TDG has an intermediate level of activity in excision of U and is severely inhibited in its excision of T. These results are discussed in the context of cellular roles for each of these enzymes.
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Affiliation(s)
- Mary E Tarantino
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, 02912, United States
| | - Blaine J Dow
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, 21201, United States
| | - Alexander C Drohat
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, 21201, United States; University of Maryland Marlene and Stewart Greenebaum Cancer Center, Baltimore, MD, 21201, United States
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, RI, 02912, United States.
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162
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Abstract
The base excision repair (BER) pathway removes modified nucleobases that can be deleterious to an organism. BER is initiated by a glycosylase, which finds and removes these modified nucleobases. Most of the characterization of glycosylase activity has been conducted in the context of DNA oligomer substrates. However, DNA within eukaryotic organisms exists in a packaged environment with the basic unit of organization being the nucleosome core particle (NCP). The NCP is a complex substrate for repair in which a variety of factors can influence glycosylase activity. In this Review, we focus on the geometric positioning of modified nucleobases in an NCP and the consequences on glycosylase activity and initiating BER.
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Affiliation(s)
- Erin E Kennedy
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912, United States
| | - Paul J Caffrey
- Department of Chemistry, Brown University, Providence, RI 02912, United States
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, RI 02912, United States.
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163
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Shi X, Prasanna C, Nagashima T, Yamazaki T, Pervushin K, Nordenskiöld L. Structure and Dynamics in the Nucleosome Revealed by Solid-State NMR. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201804707] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Xiangyan Shi
- School of Physical and Mathematical Sciences; Nanyang Technological University; 21 Nanyang Link Singapore 637371 Singapore
| | - Chinmayi Prasanna
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
| | - Toshio Nagashima
- RIKEN Center for Life Science Technologies; Yokohama City Kanagawa 230-0045 Japan
| | - Toshio Yamazaki
- RIKEN Center for Life Science Technologies; Yokohama City Kanagawa 230-0045 Japan
| | - Konstantin Pervushin
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
| | - Lars Nordenskiöld
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
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164
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Shi X, Prasanna C, Nagashima T, Yamazaki T, Pervushin K, Nordenskiöld L. Structure and Dynamics in the Nucleosome Revealed by Solid-State NMR. Angew Chem Int Ed Engl 2018; 57:9734-9738. [DOI: 10.1002/anie.201804707] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 05/23/2018] [Indexed: 02/01/2023]
Affiliation(s)
- Xiangyan Shi
- School of Physical and Mathematical Sciences; Nanyang Technological University; 21 Nanyang Link Singapore 637371 Singapore
| | - Chinmayi Prasanna
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
| | - Toshio Nagashima
- RIKEN Center for Life Science Technologies; Yokohama City Kanagawa 230-0045 Japan
| | - Toshio Yamazaki
- RIKEN Center for Life Science Technologies; Yokohama City Kanagawa 230-0045 Japan
| | - Konstantin Pervushin
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
| | - Lars Nordenskiöld
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
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165
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Wang R, Yang K, Banerjee S, Greenberg MM. Rotational Effects within Nucleosome Core Particles on Abasic Site Reactivity. Biochemistry 2018; 57:3945-3952. [PMID: 29894168 DOI: 10.1021/acs.biochem.8b00493] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
An abasic (AP) site is a ubiquitous DNA lesion that is produced via several cellular processes. Although AP sites are cytotoxic and mutagenic, cells are protected from them by different DNA damage tolerance and repair pathways, including base excision repair (BER). AP lesions are alkali-labile, but the half-life for strand scission is several weeks in free DNA at around neutral pH. The AP lifetime is reduced ∼100-fold in nucleosome core particles (NCPs) because the histone proteins promote strand scission. The reactivity of other DNA lesions to BER enzymes and exogenous reagents is highly dependent upon rotational positioning within the NCP. We examined strand scission at AP sites as a function of rotational position over approximately one helical turn of DNA. The rate constant for strand scission at AP varies ∼4-fold, a range of reactivity much smaller than that observed for processes that involve reaction with diffusible reagents in solution. In addition, the change in rate constant does not exhibit an obvious pattern with respect to rotational position. The small dependence of reactivity on rotational position is attributed to interactions with histone proteins. A molecular model based upon NCP X-ray crystal structures indicates that histone protein tails access AP sites via the major or minor groove and are therefore not limited to regions where one particular groove is exposed to solvent. Determining the roles of individual proteins is difficult because of the unstructured nature of the histone tails and the chemical mechanism, which involves reversible Schiff base formation, followed by irreversible elimination.
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Affiliation(s)
- Ruixiang Wang
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Kun Yang
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Samya Banerjee
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Marc M Greenberg
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
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166
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Rodriguez Y, Duan M, Wyrick JJ, Smerdon MJ. A cassette of basic amino acids in histone H2B regulates nucleosome dynamics and access to DNA damage. J Biol Chem 2018; 293:7376-7386. [PMID: 29588367 PMCID: PMC5949990 DOI: 10.1074/jbc.ra117.000358] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 03/12/2018] [Indexed: 12/25/2022] Open
Abstract
Nucleosome dynamics, such as spontaneous DNA unwrapping, are postulated to have a critical role in regulating the access of DNA repair machinery to DNA lesions within nucleosomes. However, the specific histone domains that regulate nucleosome dynamics and the impact of such changes in intrinsic nucleosome dynamics on DNA repair are not well understood. Previous studies identified a highly conserved region in the N-terminal tail of histone H2B known as the histone H2Brepression (or HBR) domain, which has a significant influence on gene expression, chromatin assembly, and DNA damage formation and repair. However, the molecular mechanism(s) that may account for these observations are limited. In this study, we characterized the stability and dynamics of ΔHBR mutant nucleosome core particles (NCPs) in vitro by restriction enzyme accessibility (REA), FRET, and temperature-induced sliding of histone octamers. Our results indicate that ΔHBR-NCPs are more dynamic, with a larger steady-state fraction of the NCP population occupying the unwrapped state than for WT-NCPs. Additionally, ΔHBR-histone octamers are more susceptible to temperature-induced sliding on DNA than WT histone octamers. Furthermore, we show that the activity of base excision repair enzymes at uracil lesions and single nucleotide gaps is enhanced in a site-specific manner in ΔHBR-NCPs. This enhanced activity correlates well with regions exhibiting increased DNA unwrapping. Finally, removal of the HBR domain is not sufficient to completely alleviate the structural constraints imposed by histone octamers on the activity of base excision repair enzymes.
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Affiliation(s)
- Yesenia Rodriguez
- From Biochemistry and Biophysics, School of Molecular Biosciences, Pullman, Washington 99164-7520
| | - Mingrui Duan
- From Biochemistry and Biophysics, School of Molecular Biosciences, Pullman, Washington 99164-7520
| | - John J Wyrick
- From Biochemistry and Biophysics, School of Molecular Biosciences, Pullman, Washington 99164-7520; Center for Reproductive Biology, Washington State University, Pullman, Washington 99164-7520
| | - Michael J Smerdon
- From Biochemistry and Biophysics, School of Molecular Biosciences, Pullman, Washington 99164-7520.
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167
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Xiang S, le Paige UB, Horn V, Houben K, Baldus M, van Ingen H. Site-Specific Studies of Nucleosome Interactions by Solid-State NMR Spectroscopy. Angew Chem Int Ed Engl 2018; 57:4571-4575. [PMID: 29465771 PMCID: PMC5947581 DOI: 10.1002/anie.201713158] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/08/2018] [Indexed: 01/01/2023]
Abstract
Chromatin function depends on a dense network of interactions between nucleosomes and a wide range of proteins. A detailed description of these protein-nucleosome interactions is required to reach a full molecular understanding of chromatin function in both genetics and epigenetics. Herein, we show that the structure, dynamics, and interactions of nucleosomes can be interrogated in a residue-specific manner by using state-of-the-art solid-state NMR spectroscopy. Using sedimented nucleosomes, high-resolution spectra were obtained for both flexible histone tails and the non-mobile histone core. Through co-sedimentation of a nucleosome-binding peptide, we demonstrate that protein-binding sites on the nucleosome surface can be determined. We believe that this approach holds great promise as it is generally applicable, extendable to include the structure and dynamics of the bound proteins, and scalable to interactions of proteins with higher-order chromatin structures, including isolated and cellular chromatin.
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Affiliation(s)
- ShengQi Xiang
- NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Ulric B. le Paige
- Macromolecular BiochemistryLeiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeidenThe Netherlands
- Current address: NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Velten Horn
- Macromolecular BiochemistryLeiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeidenThe Netherlands
- Current address: NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Klaartje Houben
- NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
- Current address: DSM Food SpecialtiesDSM Biotechnology CenterAlexander Flemminglaan 12613 AXDelftThe Netherlands
| | - Marc Baldus
- NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Hugo van Ingen
- Macromolecular BiochemistryLeiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeidenThe Netherlands
- Current address: NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
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168
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Isogawa A, Fuchs RP, Fujii S. Versatile and efficient chromatin pull-down methodology based on DNA triple helix formation. Sci Rep 2018; 8:5925. [PMID: 29651103 PMCID: PMC5897567 DOI: 10.1038/s41598-018-24417-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 03/23/2018] [Indexed: 11/09/2022] Open
Abstract
The goal of present paper is to develop a reliable DNA-based method for isolation of protein complexes bound to DNA (Isolation of DNA Associated Proteins: IDAP). We describe a robust and versatile procedure to pull-down chromatinized DNA sequences-of-interest by formation of a triple helix between a sequence tag present in the DNA and a complementary triple helix forming oligonucleotide (TFO) coupled to a desthiobiotin residue. Following optimization to insure efficient recovery of native plasmids via TFO probe in vitro, the procedure is shown to work under various experimental situations. For instance, it allows capture proteins associated to plasmids hosted in E. coli, and is also successfully applied to recovering nucleosomes in vitro opening many possibilities to study post translational modifications of histones in a genuine nucleosome context. Incubation in human nuclear extracts of a plasmid carrying a NF-κB model promoter is shown to pull-down a specific transcription factor. Finally, isolation of a specific locus from human genomic chromatin has been successfully achieved (Chromatin-of-Interest Fragment Isolation: CoIFI). In conclusion, the methodology can be implemented for capturing proteins that specifically bind to any sequence-of-interest, DNA adduct or secondary structure provided a short sequence tag for triple helix formation is located nearby.
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Affiliation(s)
- Asako Isogawa
- DNA Damage Tolerance CNRS, UMR7258, Marseille, F-13009, France.,Inserm, U1068, CRCM, Marseille, F-13009, France.,Institut Paoli-Calmettes, Marseille, F-13009, France.,Aix-Marseille University, UM 105, F-13284, Marseille, France
| | - Robert P Fuchs
- DNA Damage Tolerance CNRS, UMR7258, Marseille, F-13009, France. .,Inserm, U1068, CRCM, Marseille, F-13009, France. .,Institut Paoli-Calmettes, Marseille, F-13009, France. .,Aix-Marseille University, UM 105, F-13284, Marseille, France. .,Harvard Medical School, Boston, MA, 02115, USA.
| | - Shingo Fujii
- DNA Damage Tolerance CNRS, UMR7258, Marseille, F-13009, France. .,Inserm, U1068, CRCM, Marseille, F-13009, France. .,Institut Paoli-Calmettes, Marseille, F-13009, France. .,Aix-Marseille University, UM 105, F-13284, Marseille, France.
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169
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Brandani GB, Niina T, Tan C, Takada S. DNA sliding in nucleosomes via twist defect propagation revealed by molecular simulations. Nucleic Acids Res 2018; 46:2788-2801. [PMID: 29506273 PMCID: PMC5887990 DOI: 10.1093/nar/gky158] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/05/2018] [Accepted: 02/20/2018] [Indexed: 11/13/2022] Open
Abstract
While nucleosomes are highly stable structures as fundamental units of chromatin, they also slide along the DNA, either spontaneously or by active remodelers. Here, we investigate the microscopic mechanisms of nucleosome sliding by multiscale molecular simulations, characterizing how the screw-like motion of DNA proceeds via the formation and propagation of twist defects. Firstly, coarse-grained molecular simulations reveal that the sliding dynamics is highly dependent on DNA sequence. Depending on the sequence and the nucleosome super-helical location, we find two distinct types of twist defects: a locally under-twisted DNA region, previously observed in crystal structures, and a locally over-twisted DNA, an unprecedented feature. The stability of the over-twist defect was confirmed via all-atom simulations. Analysis of our trajectories via Markov state modeling highlights how the sequence-dependence of the sliding dynamics is due to the different twist defect energy costs, and in particular how nucleosome regions where defects cannot easily form introduce the kinetic bottlenecks slowing down repositioning. Twist defects can also mediate sliding of nucleosomes made with strong positioning sequences, albeit at a much lower diffusion coefficient, due to a high-energy intermediate state. Finally, we discuss how chromatin remodelers may exploit these spontaneous fluctuations to induce unidirectional sliding of nucleosomes.
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Affiliation(s)
- Giovanni B Brandani
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Toru Niina
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Cheng Tan
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Shoji Takada
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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170
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Structural rearrangements of the histone octamer translocate DNA. Nat Commun 2018; 9:1330. [PMID: 29626188 PMCID: PMC5889399 DOI: 10.1038/s41467-018-03677-z] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 03/05/2018] [Indexed: 01/28/2023] Open
Abstract
Nucleosomes, the basic unit of chromatin, package and regulate expression of eukaryotic genomes. Nucleosomes are highly dynamic and are remodeled with the help of ATP-dependent remodeling factors. Yet, the mechanism of DNA translocation around the histone octamer is poorly understood. In this study, we present several nucleosome structures showing histone proteins and DNA in different organizational states. We observe that the histone octamer undergoes conformational changes that distort the overall nucleosome structure. As such, rearrangements in the histone core α-helices and DNA induce strain that distorts and moves DNA at SHL 2. Distortion of the nucleosome structure detaches histone α-helices from the DNA, leading to their rearrangement and DNA translocation. Biochemical assays show that cross-linked histone octamers are immobilized on DNA, indicating that structural changes in the octamer move DNA. This intrinsic plasticity of the nucleosome is exploited by chromatin remodelers and might be used by other chromatin machineries.
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171
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Xiang S, le Paige UB, Horn V, Houben K, Baldus M, van Ingen H. Site‐Specific Studies of Nucleosome Interactions by Solid‐State NMR Spectroscopy. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201713158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- ShengQi Xiang
- NMR Spectroscopy Research Group Bijvoet Center for Biomolecular Research Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands
| | - Ulric B. le Paige
- Macromolecular Biochemistry Leiden Institute of Chemistry Leiden University Einsteinweg 55 2333 CC Leiden The Netherlands
- Current address: NMR Spectroscopy Research Group Bijvoet Center for Biomolecular Research Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands
| | - Velten Horn
- Macromolecular Biochemistry Leiden Institute of Chemistry Leiden University Einsteinweg 55 2333 CC Leiden The Netherlands
- Current address: NMR Spectroscopy Research Group Bijvoet Center for Biomolecular Research Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands
| | - Klaartje Houben
- NMR Spectroscopy Research Group Bijvoet Center for Biomolecular Research Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands
- Current address: DSM Food Specialties DSM Biotechnology Center Alexander Flemminglaan 1 2613 AX Delft The Netherlands
| | - Marc Baldus
- NMR Spectroscopy Research Group Bijvoet Center for Biomolecular Research Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands
| | - Hugo van Ingen
- Macromolecular Biochemistry Leiden Institute of Chemistry Leiden University Einsteinweg 55 2333 CC Leiden The Netherlands
- Current address: NMR Spectroscopy Research Group Bijvoet Center for Biomolecular Research Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands
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172
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Cryo-EM structures of PRC2 simultaneously engaged with two functionally distinct nucleosomes. Nat Struct Mol Biol 2018; 25:154-162. [PMID: 29379173 PMCID: PMC5805599 DOI: 10.1038/s41594-018-0023-y] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 12/21/2017] [Indexed: 11/08/2022]
Abstract
Epigenetic regulation is mediated by protein complexes that couple recognition of chromatin marks to activity or recruitment of chromatin-modifying enzymes. Polycomb repressive complex 2 (PRC2), a gene silencer that methylates lysine 27 of histone H3, is stimulated upon recognition of its own catalytic product and has been shown to be more active on dinucleosomes than H3 tails or single nucleosomes. These properties probably facilitate local H3K27me2/3 spreading, causing heterochromatin formation and gene repression. Here, cryo-EM reconstructions of human PRC2 bound to bifunctional dinucleosomes show how a single PRC2, via interactions with nucleosomal DNA, positions the H3 tails of the activating and substrate nucleosome to interact with the EED subunit and the SET domain of EZH2, respectively. We show how the geometry of the PRC2-DNA interactions allows PRC2 to accommodate varying lengths of the linker DNA between nucleosomes. Our structures illustrate how an epigenetic regulator engages with a complex chromatin substrate.
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173
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Schwarz M, Schall K, Kallis E, Eustermann S, Guariento M, Moldt M, Hopfner KP, Michaelis J. Single-molecule nucleosome remodeling by INO80 and effects of histone tails. FEBS Lett 2018; 592:318-331. [PMID: 29331030 DOI: 10.1002/1873-3468.12973] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 12/22/2017] [Accepted: 12/29/2017] [Indexed: 01/30/2023]
Abstract
Genome maintenance and integrity requires continuous alterations of the compaction state of the chromatin structure. Chromatin remodelers, among others the INO80 complex, help organize chromatin by repositioning, reshaping, or evicting nucleosomes. We report on INO80 nucleosome remodeling, assayed by single-molecule Foerster resonance energy transfer on canonical nucleosomes as well as nucleosomes assembled from tailless histones. Nucleosome repositioning by INO80 is a processively catalyzed reaction. During the initiation of remodeling, probed by the INO80 bound state, the nucleosome reveals structurally heterogeneous states for tailless nucleosomes (in contrast to wild-type nucleosomes). We, therefore, propose an altered energy landscape for the INO80-mediated nucleosome sliding reaction in the absence of histone tails.
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Affiliation(s)
- Marianne Schwarz
- Faculty of Natural Sciences, Institute of Biophysics, Ulm University, Germany.,Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Kevin Schall
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Eleni Kallis
- Faculty of Natural Sciences, Institute of Biophysics, Ulm University, Germany
| | - Sebastian Eustermann
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Mara Guariento
- Faculty of Natural Sciences, Institute of Biophysics, Ulm University, Germany
| | - Manuela Moldt
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Karl-Peter Hopfner
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Jens Michaelis
- Faculty of Natural Sciences, Institute of Biophysics, Ulm University, Germany
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174
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Korolev N, Lyubartsev AP, Nordenskiöld L. A systematic analysis of nucleosome core particle and nucleosome-nucleosome stacking structure. Sci Rep 2018; 8:1543. [PMID: 29367745 PMCID: PMC5784010 DOI: 10.1038/s41598-018-19875-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 01/04/2018] [Indexed: 12/13/2022] Open
Abstract
Chromatin condensation is driven by the energetically favourable interaction between nucleosome core particles (NCPs). The close NCP-NCP contact, stacking, is a primary structural element of all condensed states of chromatin in vitro and in vivo. However, the molecular structure of stacked nucleosomes as well as the nature of the interactions involved in its formation have not yet been systematically studied. Here we undertake an investigation of both the structural and physico-chemical features of NCP structure and the NCP-NCP stacking. We introduce an “NCP-centred” set of parameters (NCP-NCP distance, shift, rise, tilt, and others) that allows numerical characterisation of the mutual positions of the NCPs in the stacking and in any other structures formed by the NCP. NCP stacking in more than 140 published NCP crystal structures were analysed. In addition, coarse grained (CG) MD simulations modelling NCP condensation was carried out. The CG model takes into account details of the nucleosome structure and adequately describes the long range electrostatic forces as well as excluded volume effects acting in chromatin. The CG simulations showed good agreement with experimental data and revealed the importance of the H2A and H4 N-terminal tail bridging and screening as well as tail-tail correlations in the stacked nucleosomes.
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Affiliation(s)
- Nikolay Korolev
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore.
| | - Alexander P Lyubartsev
- Department of Materials and Environmental Chemistry, Stockholm University, 10691, Stockholm, Sweden
| | - Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore.
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175
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Bilotti K, Tarantino ME, Delaney S. Human Oxoguanine Glycosylase 1 Removes Solution Accessible 8-Oxo-7,8-dihydroguanine Lesions from Globally Substituted Nucleosomes Except in the Dyad Region. Biochemistry 2018; 57:1436-1439. [DOI: 10.1021/acs.biochem.7b01125] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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176
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Structural Basis of Heterochromatin Formation by Human HP1. Mol Cell 2018; 69:385-397.e8. [PMID: 29336876 DOI: 10.1016/j.molcel.2017.12.011] [Citation(s) in RCA: 167] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 11/01/2017] [Accepted: 12/13/2017] [Indexed: 12/17/2022]
Abstract
Heterochromatin plays important roles in transcriptional silencing and genome maintenance by the formation of condensed chromatin structures, which determine the epigenetic status of eukaryotic cells. The trimethylation of histone H3 lysine 9 (H3K9me3), a target of heterochromatin protein 1 (HP1), is a hallmark of heterochromatin formation. However, the mechanism by which HP1 folds chromatin-containing H3K9me3 into a higher-order structure has not been elucidated. Here we report the three-dimensional structure of the H3K9me3-containing dinucleosomes complexed with human HP1α, HP1β, and HP1γ, determined by cryogenic electron microscopy with a Volta phase plate. In the structures, two H3K9me3 nucleosomes are bridged by a symmetric HP1 dimer. Surprisingly, the linker DNA between the nucleosomes does not directly interact with HP1, thus allowing nucleosome remodeling by the ATP-utilizing chromatin assembly and remodeling factor (ACF). The structure depicts the fundamental architecture of heterochromatin.
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177
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Saha A, Kizaki S, Han JH, Yu Z, Sugiyama H. UVA irradiation of BrU-substituted DNA in the presence of Hoechst 33258. Bioorg Med Chem 2018; 26:37-40. [PMID: 29170027 DOI: 10.1016/j.bmc.2017.11.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 11/02/2017] [Accepted: 11/04/2017] [Indexed: 01/15/2023]
Abstract
Given that our knowledge of DNA repair is limited because of the complexity of the DNA system, a technique called UVA micro-irradiation has been developed that can be used to visualize the recruitment of DNA repair proteins at double-strand break (DSB) sites. Interestingly, Hoechst 33258 was used under micro-irradiation to sensitize 5-bromouracil (BrU)-labelled DNA, causing efficient DSBs. However, the molecular basis of DSB formation under UVA micro-irradiation remains unknown. Herein, we investigated the mechanism of DSB formation under UVA micro-irradiation conditions. Our results suggest that the generation of a uracil-5-yl radical through electron transfer from Hoechst 33258 to BrU caused DNA cleavage preferentially at self-complementary 5'-AABrUBrU-3' sequences to induce DSB. We also investigated the DNA cleavage in the context of the nucleosome to gain a better understanding of UVA micro-irradiation in a cell-like model. We found that DNA cleavage occurred in both core and linker DNA regions although its efficiency reduced in core DNA.
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Affiliation(s)
- Abhijit Saha
- Department of Science, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Seiichiro Kizaki
- Department of Science, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Ji Hoon Han
- Department of Science, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Zutao Yu
- Department of Science, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Hiroshi Sugiyama
- Department of Science, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8501, Japan; Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Yoshida Ushinomiya-cho, Sakyo, Kyoto 606-8502, Japan.
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178
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Pentakota S, Zhou K, Smith C, Maffini S, Petrovic A, Morgan GP, Weir JR, Vetter IR, Musacchio A, Luger K. Decoding the centromeric nucleosome through CENP-N. eLife 2017; 6:33442. [PMID: 29280735 PMCID: PMC5777823 DOI: 10.7554/elife.33442] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 12/23/2017] [Indexed: 02/07/2023] Open
Abstract
Centromere protein (CENP) A, a histone H3 variant, is a key epigenetic determinant of chromosome domains known as centromeres. Centromeres nucleate kinetochores, multi-subunit complexes that capture spindle microtubules to promote chromosome segregation during mitosis. Two kinetochore proteins, CENP-C and CENP-N, recognize CENP-A in the context of a rare CENP-A nucleosome. Here, we reveal the structural basis for the exquisite selectivity of CENP-N for centromeres. CENP-N uses charge and space complementarity to decode the L1 loop that is unique to CENP-A. It also engages in extensive interactions with a 15-base pair segment of the distorted nucleosomal DNA double helix, in a position predicted to exclude chromatin remodelling enzymes. Besides CENP-A, stable centromere recruitment of CENP-N requires a coincident interaction with a newly identified binding motif on nucleosome-bound CENP-C. Collectively, our studies clarify how CENP-N and CENP-C decode and stabilize the non-canonical CENP-A nucleosome to enforce epigenetic centromere specification and kinetochore assembly.
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Affiliation(s)
- Satyakrishna Pentakota
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Keda Zhou
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, United States
| | - Charlotte Smith
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Stefano Maffini
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Arsen Petrovic
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Garry P Morgan
- Department of MCDB, University of Colorado at Boulder, Boulder, United States
| | - John R Weir
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany.,Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Essen, Germany
| | - Karolin Luger
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, United States.,Howard Hughes Medical Institute, Maryland, United States
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179
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Chittori S, Hong J, Saunders H, Feng H, Ghirlando R, Kelly AE, Bai Y, Subramaniam S. Structural mechanisms of centromeric nucleosome recognition by the kinetochore protein CENP-N. Science 2017; 359:339-343. [PMID: 29269420 DOI: 10.1126/science.aar2781] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/12/2017] [Indexed: 11/02/2022]
Abstract
Accurate chromosome segregation requires the proper assembly of kinetochore proteins. A key step in this process is the recognition of the histone H3 variant CENP-A in the centromeric nucleosome by the kinetochore protein CENP-N. We report cryo-electron microscopy (cryo-EM), biophysical, biochemical, and cell biological studies of the interaction between the CENP-A nucleosome and CENP-N. We show that human CENP-N confers binding specificity through interactions with the L1 loop of CENP-A, stabilized by electrostatic interactions with the nucleosomal DNA. Mutational analyses demonstrate analogous interactions in Xenopus, which are further supported by residue-swapping experiments involving the L1 loop of CENP-A. Our results are consistent with the coevolution of CENP-N and CENP-A and establish the structural basis for recognition of the CENP-A nucleosome to enable kinetochore assembly and centromeric chromatin organization.
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Affiliation(s)
- Sagar Chittori
- Laboratory of Cell Biology, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Jingjun Hong
- Laboratory of Biochemistry and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA
| | - Hayden Saunders
- Laboratory of Biochemistry and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA
| | - Hanqiao Feng
- Laboratory of Biochemistry and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, MD 20892, USA
| | - Alexander E Kelly
- Laboratory of Biochemistry and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA.
| | - Yawen Bai
- Laboratory of Biochemistry and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA.
| | - Sriram Subramaniam
- Laboratory of Cell Biology, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA.
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180
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Histone octamer rearranges to adapt to DNA unwrapping. Nat Struct Mol Biol 2017; 25:101-108. [PMID: 29323273 PMCID: PMC5800490 DOI: 10.1038/s41594-017-0005-5] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 11/03/2017] [Indexed: 11/12/2022]
Abstract
Nucleosomes, the basic unit of chromatin, package and regulate expression of eukaryotic genomes. Although the structure of the intact nucleosome has been studied, little is known about structures of its partially unwrapped, transient intermediates. In this study, we present 9 cryo EM structures of distinct conformations of nucleosome and subnucleosome particles. Our structures show that initial DNA breathing induces conformational changes in the histone octamer, particularly in histone H3, that propagate through the nucleosome and prevent symmetrical DNA opening. Rearrangements in the H2A–H2B dimer strengthen interaction with the unwrapping DNA and promote nucleosome stability. In agreement, cross-linked H2A–H2B that can not accommodate to the unwrapping of the DNA is not stably maintained in the nucleosome. H2A–H2B release and DNA unwrapping occur simultaneously indicating that DNA is essential in stabilizing the dimer in the nucleosome. Our structures reveal intrinsic nucleosomal plasticity that is required for nucleosome stability and might be exploited by extrinsic protein factors.
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181
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Niina T, Brandani GB, Tan C, Takada S. Sequence-dependent nucleosome sliding in rotation-coupled and uncoupled modes revealed by molecular simulations. PLoS Comput Biol 2017; 13:e1005880. [PMID: 29194442 PMCID: PMC5728581 DOI: 10.1371/journal.pcbi.1005880] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 12/13/2017] [Accepted: 11/11/2017] [Indexed: 12/12/2022] Open
Abstract
While nucleosome positioning on eukaryotic genome play important roles for genetic regulation, molecular mechanisms of nucleosome positioning and sliding along DNA are not well understood. Here we investigated thermally-activated spontaneous nucleosome sliding mechanisms developing and applying a coarse-grained molecular simulation method that incorporates both long-range electrostatic and short-range hydrogen-bond interactions between histone octamer and DNA. The simulations revealed two distinct sliding modes depending on the nucleosomal DNA sequence. A uniform DNA sequence showed frequent sliding with one base pair step in a rotation-coupled manner, akin to screw-like motions. On the contrary, a strong positioning sequence, the so-called 601 sequence, exhibits rare, abrupt transitions of five and ten base pair steps without rotation. Moreover, we evaluated the importance of hydrogen bond interactions on the sliding mode, finding that strong and weak bonds favor respectively the rotation-coupled and -uncoupled sliding movements.
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Affiliation(s)
- Toru Niina
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Giovanni B. Brandani
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Cheng Tan
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Shoji Takada
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
- * E-mail:
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182
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Koyama M, Kurumizaka H. Structural diversity of the nucleosome. J Biochem 2017; 163:85-95. [DOI: 10.1093/jb/mvx081] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 10/31/2017] [Indexed: 02/06/2023] Open
Affiliation(s)
- Masako Koyama
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
- Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
- Institute for Medical-Oriented Structural Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
- Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
- Institute for Medical-Oriented Structural Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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183
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Frouws TD, Barth PD, Richmond TJ. Site-Specific Disulfide Crosslinked Nucleosomes with Enhanced Stability. J Mol Biol 2017; 430:45-57. [PMID: 29113904 PMCID: PMC5757783 DOI: 10.1016/j.jmb.2017.10.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 10/24/2017] [Accepted: 10/25/2017] [Indexed: 12/04/2022]
Abstract
We engineered nucleosome core particles (NCPs) with two site-specific cysteine crosslinks that increase the stability of the particle. The first disulfide was introduced between the two copies of H2A via an H2A-N38C point mutation, effectively crosslinking the two H2A/H2B heterodimers together to stabilize the histone octamer against H2A/H2B dimer dissociation. The second crosslink was engineered between an R40C point mutation on the N-terminal tail of H3 and the NCP DNA ends by the introduction of a convertible nucleotide. This crosslink maintains the nucleosome DNA in a fixed translational setting relative to the histone octamer and prevents dilution-driven dissociation. The X-ray crystal structures of NCPs containing the disulfides in isolation and in combination were determined. Both disulfides stabilize the structure of the NCP without disturbing the overall structure. Nucleosomes containing these modifications will be advantageous for biochemical and structural studies as a consequence of their greater resistance to dissociation during high dilution in purification, elevated salt for crystallization and vitrification for cryogenic electron microscopy. Crosslinked nucleosome core particles have increased stability against H2A/H2B dimer loss and DNA dissociation. A site-specific disulfide crosslink was introduced between the two copies of H2A in the histone octamer to stabilize its quaternary structure. Site-specific disulfide crosslinks were introduced between histone H3 and DNA within the nucleosome core particle. Three X-ray crystal structures of crosslinked nucleosome core particles were determined at high resolution.
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Affiliation(s)
- Timothy D Frouws
- ETH Zürich, Institute of Molecular Biology and Biophysics, Otto-Stern-Weg 5, 8093 Zürich, Switzerland
| | - Philip D Barth
- ETH Zürich, Institute of Molecular Biology and Biophysics, Otto-Stern-Weg 5, 8093 Zürich, Switzerland
| | - Timothy J Richmond
- ETH Zürich, Institute of Molecular Biology and Biophysics, Otto-Stern-Weg 5, 8093 Zürich, Switzerland.
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184
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Shaytan AK, Xiao H, Armeev GA, Wu C, Landsman D, Panchenko AR. Hydroxyl-radical footprinting combined with molecular modeling identifies unique features of DNA conformation and nucleosome positioning. Nucleic Acids Res 2017; 45:9229-9243. [PMID: 28934480 PMCID: PMC5765820 DOI: 10.1093/nar/gkx616] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 07/05/2017] [Indexed: 01/08/2023] Open
Abstract
Nucleosomes are the most abundant protein–DNA complexes in eukaryotes that provide compaction of genomic DNA and are implicated in regulation of transcription, DNA replication and repair. The details of DNA positioning on the nucleosome and the DNA conformation can provide key regulatory signals. Hydroxyl-radical footprinting (HRF) of protein–DNA complexes is a chemical technique that probes nucleosome organization in solution with a high precision unattainable by other methods. In this work we propose an integrative modeling method for constructing high-resolution atomistic models of nucleosomes based on HRF experiments. Our method precisely identifies DNA positioning on nucleosome by combining HRF data for both DNA strands with the pseudo-symmetry constraints. We performed high-resolution HRF for Saccharomyces cerevisiae centromeric nucleosome of unknown structure and characterized it using our integrative modeling approach. Our model provides the basis for further understanding the cooperative engagement and interplay between Cse4p protein and the A-tracts important for centromere function.
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Affiliation(s)
- Alexey K Shaytan
- National Center for Biotechnology Information, NLM, NIH, Bethesda, MD 20894, USA.,Department of Biology, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Hua Xiao
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Grigoriy A Armeev
- Department of Biology, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Carl Wu
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.,Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.,Department of Biology, Johns Hopkins University, 3400 N. Charles Street-UTL 387, Baltimore, MD 21218, USA.,Department of Molecular Biology & Genetics, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA
| | - David Landsman
- National Center for Biotechnology Information, NLM, NIH, Bethesda, MD 20894, USA
| | - Anna R Panchenko
- National Center for Biotechnology Information, NLM, NIH, Bethesda, MD 20894, USA
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185
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Nucleosome-Chd1 structure and implications for chromatin remodelling. Nature 2017; 550:539-542. [PMID: 29019976 PMCID: PMC5697743 DOI: 10.1038/nature24046] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 08/30/2017] [Indexed: 12/16/2022]
Abstract
Chromatin remodelling factors change nucleosome positioning and
facilitate DNA transcription, replication, and repair1. The conserved remodelling factor Chd12 can shift nucleosomes and induce a regular
nucleosome spacing3–5. Chd1 is required for RNA polymerase II
passage through nucleosomes6 and for
cellular pluripotency7. Chd1 contains the
DNA-binding domains SANT and SLIDE, a bilobal motor domain that hydrolyses
adenosine triphosphate (ATP), and a regulatory double chromodomain. Here we
report the cryo-electron microscopy (cryo-EM) structure of Chd1 from the yeast
S. cerevisiae bound to a nucleosome at a resolution of 4.8
Å. Chd1 detaches two turns of DNA from the histone octamer and binds
between the two DNA gyres in a state poised for catalysis. The SANT and SLIDE
domains contact detached DNA around superhelical location (SHL) -7 of the first
DNA gyre. The ATPase motor binds the second DNA gyre at SHL +2 and is anchored
to the N-terminal tail of histone H4 as in a recent nucleosome-Snf2 ATPase
structure8. Comparison with published
results9 reveals that the double
chromodomain swings towards nucleosomal DNA at SHL +1, resulting in ATPase
closure. The ATPase can then promote translocation of DNA towards the nucleosome
dyad, thereby loosening the first DNA gyre and remodelling the nucleosome.
Translocation may involve ratcheting of the two lobes of the ATPase, which is
trapped in a pre- or post-translocated state in the absence8 or presence, respectively, of transition state-mimicking
compounds.
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186
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Ekundayo B, Richmond TJ, Schalch T. Capturing Structural Heterogeneity in Chromatin Fibers. J Mol Biol 2017; 429:3031-3042. [PMID: 28893533 DOI: 10.1016/j.jmb.2017.09.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 09/01/2017] [Accepted: 09/03/2017] [Indexed: 10/18/2022]
Abstract
Chromatin fiber organization is implicated in processes such as transcription, DNA repair and chromosome segregation, but how nucleosomes interact to form higher-order structure remains poorly understood. We solved two crystal structures of tetranucleosomes with approximately 11-bp DNA linker length at 5.8 and 6.7 Å resolution. Minimal intramolecular nucleosome-nucleosome interactions result in a fiber model resembling a flat ribbon that is compatible with a two-start helical architecture, and that exposes histone and DNA surfaces to the environment. The differences in the two structures combined with electron microscopy reveal heterogeneous structural states, and we used site-specific chemical crosslinking to assess the diversity of nucleosome-nucleosome interactions through identification of structure-sensitive crosslink sites that provide a means to characterize fibers in solution. The chromatin fiber architectures observed here provide a basis for understanding heterogeneous chromatin higher-order structures as they occur in a genomic context.
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Affiliation(s)
- Babatunde Ekundayo
- Department of Molecular Biology, Faculty of Sciences, University of Geneva, CH-1211 Geneva 4, Switzerland; Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, CH-1211 Geneva 4, Switzerland
| | - Timothy J Richmond
- Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, CH-8093 Zurich, Switzerland
| | - Thomas Schalch
- Department of Molecular Biology, Faculty of Sciences, University of Geneva, CH-1211 Geneva 4, Switzerland; Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, CH-1211 Geneva 4, Switzerland.
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187
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Rodriguez Y, Howard MJ, Cuneo MJ, Prasad R, Wilson SH. Unencumbered Pol β lyase activity in nucleosome core particles. Nucleic Acids Res 2017; 45:8901-8915. [PMID: 28911106 PMCID: PMC5587807 DOI: 10.1093/nar/gkx593] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/23/2017] [Accepted: 06/30/2017] [Indexed: 12/11/2022] Open
Abstract
Packaging of DNA into the nucleosome core particle (NCP) is considered to exert constraints to all DNA-templated processes, including base excision repair where Pol β catalyzes two key enzymatic steps: 5'-dRP lyase gap trimming and template-directed DNA synthesis. Despite its biological significance, knowledge of Pol β activities on NCPs is still limited. Here, we show that removal of the 5'-dRP block by Pol β is unaffected by NCP constraints at all sites tested and is even enhanced near the DNA ends. In contrast, strong inhibition of DNA synthesis is observed. These results indicate 5'-dRP gap trimming proceeds unperturbed within the NCP; whereas, gap filling is strongly limited. In the absence of additional factors, base excision repair in NCPs will stall at the gap-filling step.
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Affiliation(s)
- Yesenia Rodriguez
- From the Laboratory of Genome Integrity and Structural Biology, NIEHS-NIH, Research Triangle Park, NC 27709, USA
| | - Michael J. Howard
- From the Laboratory of Genome Integrity and Structural Biology, NIEHS-NIH, Research Triangle Park, NC 27709, USA
| | | | - Rajendra Prasad
- From the Laboratory of Genome Integrity and Structural Biology, NIEHS-NIH, Research Triangle Park, NC 27709, USA
| | - Samuel H. Wilson
- From the Laboratory of Genome Integrity and Structural Biology, NIEHS-NIH, Research Triangle Park, NC 27709, USA
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188
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Catalytic-Independent Functions of PARP-1 Determine Sox2 Pioneer Activity at Intractable Genomic Loci. Mol Cell 2017; 65:589-603.e9. [PMID: 28212747 DOI: 10.1016/j.molcel.2017.01.017] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 11/30/2016] [Accepted: 01/13/2017] [Indexed: 01/09/2023]
Abstract
Pioneer transcription factors (TFs) function as genomic first responders, binding to inaccessible regions of chromatin to promote enhancer formation. The mechanism by which pioneer TFs gain access to chromatin remains an important unanswered question. Here we show that PARP-1, a nucleosome-binding protein, cooperates with intrinsic properties of the pioneer TF Sox2 to facilitate its binding to intractable genomic loci in embryonic stem cells. These actions of PARP-1 occur independently of its poly(ADP-ribosyl) transferase activity. PARP-1-dependent Sox2-binding sites reside in euchromatic regions of the genome with relatively high nucleosome occupancy and low co-occupancy by other transcription factors. PARP-1 stabilizes Sox2 binding to nucleosomes at suboptimal sites through cooperative interactions on DNA. Our results define intrinsic and extrinsic features that determine Sox2 pioneer activity. The conditional pioneer activity observed with Sox2 at a subset of binding sites may be a key feature of other pioneer TFs operating at intractable genomic loci.
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189
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Bednar J, Garcia-Saez I, Boopathi R, Cutter AR, Papai G, Reymer A, Syed SH, Lone IN, Tonchev O, Crucifix C, Menoni H, Papin C, Skoufias DA, Kurumizaka H, Lavery R, Hamiche A, Hayes JJ, Schultz P, Angelov D, Petosa C, Dimitrov S. Structure and Dynamics of a 197 bp Nucleosome in Complex with Linker Histone H1. Mol Cell 2017; 66:384-397.e8. [PMID: 28475873 DOI: 10.1016/j.molcel.2017.04.012] [Citation(s) in RCA: 176] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 03/08/2017] [Accepted: 04/17/2017] [Indexed: 10/19/2022]
Abstract
Linker histones associate with nucleosomes to promote the formation of higher-order chromatin structure, but the underlying molecular details are unclear. We investigated the structure of a 197 bp nucleosome bearing symmetric 25 bp linker DNA arms in complex with vertebrate linker histone H1. We determined electron cryo-microscopy (cryo-EM) and crystal structures of unbound and H1-bound nucleosomes and validated these structures by site-directed protein cross-linking and hydroxyl radical footprinting experiments. Histone H1 shifts the conformational landscape of the nucleosome by drawing the two linkers together and reducing their flexibility. The H1 C-terminal domain (CTD) localizes primarily to a single linker, while the H1 globular domain contacts the nucleosome dyad and both linkers, associating more closely with the CTD-distal linker. These findings reveal that H1 imparts a strong degree of asymmetry to the nucleosome, which is likely to influence the assembly and architecture of higher-order structures.
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Affiliation(s)
- Jan Bednar
- Institut for Advanced Biosciences, Inserm U 1209, CNRS UMR 5309, Université Grenoble Alpes, 38000 Grenoble, France
| | - Isabel Garcia-Saez
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, 38044 Grenoble, France
| | - Ramachandran Boopathi
- Institut for Advanced Biosciences, Inserm U 1209, CNRS UMR 5309, Université Grenoble Alpes, 38000 Grenoble, France; Université de Lyon, Institut NeuroMyoGène (INMG) CNRS/UCBL UMR5310 & Laboratoire de Biologie et de Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL, Ecole Normale Supérieure de Lyon, 69007 Lyon, France
| | - Amber R Cutter
- Department of Biochemistry and Biophysics, University of Rochester, Rochester, New York 14642, USA
| | - Gabor Papai
- Department of Integrated Structural Biology, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC)/Université de Strasbourg/CNRS/INSERM, 67404 Illkirch Cedex, France
| | - Anna Reymer
- MMSB, University of Lyon I/CNRS UMR 5086, Institut de Biologie et Chimie des Protéines, 69367 Lyon, France
| | - Sajad H Syed
- Institut for Advanced Biosciences, Inserm U 1209, CNRS UMR 5309, Université Grenoble Alpes, 38000 Grenoble, France; Université de Lyon, Institut NeuroMyoGène (INMG) CNRS/UCBL UMR5310 & Laboratoire de Biologie et de Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL, Ecole Normale Supérieure de Lyon, 69007 Lyon, France
| | - Imtiaz Nisar Lone
- Institut for Advanced Biosciences, Inserm U 1209, CNRS UMR 5309, Université Grenoble Alpes, 38000 Grenoble, France; Université de Lyon, Institut NeuroMyoGène (INMG) CNRS/UCBL UMR5310 & Laboratoire de Biologie et de Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL, Ecole Normale Supérieure de Lyon, 69007 Lyon, France
| | - Ognyan Tonchev
- Institut for Advanced Biosciences, Inserm U 1209, CNRS UMR 5309, Université Grenoble Alpes, 38000 Grenoble, France; Université de Lyon, Institut NeuroMyoGène (INMG) CNRS/UCBL UMR5310 & Laboratoire de Biologie et de Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL, Ecole Normale Supérieure de Lyon, 69007 Lyon, France
| | - Corinne Crucifix
- Department of Integrated Structural Biology, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC)/Université de Strasbourg/CNRS/INSERM, 67404 Illkirch Cedex, France
| | - Hervé Menoni
- Institut for Advanced Biosciences, Inserm U 1209, CNRS UMR 5309, Université Grenoble Alpes, 38000 Grenoble, France; Université de Lyon, Institut NeuroMyoGène (INMG) CNRS/UCBL UMR5310 & Laboratoire de Biologie et de Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL, Ecole Normale Supérieure de Lyon, 69007 Lyon, France
| | - Christophe Papin
- Département de Génomique Fonctionnelle et Cancer, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC)/Université de Strasbourg/CNRS/INSERM, 67404 Illkirch Cedex, France
| | - Dimitrios A Skoufias
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, 38044 Grenoble, France
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Richard Lavery
- MMSB, University of Lyon I/CNRS UMR 5086, Institut de Biologie et Chimie des Protéines, 69367 Lyon, France
| | - Ali Hamiche
- Département de Génomique Fonctionnelle et Cancer, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC)/Université de Strasbourg/CNRS/INSERM, 67404 Illkirch Cedex, France.
| | - Jeffrey J Hayes
- Department of Biochemistry and Biophysics, University of Rochester, Rochester, New York 14642, USA.
| | - Patrick Schultz
- Department of Integrated Structural Biology, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC)/Université de Strasbourg/CNRS/INSERM, 67404 Illkirch Cedex, France.
| | - Dimitar Angelov
- Université de Lyon, Institut NeuroMyoGène (INMG) CNRS/UCBL UMR5310 & Laboratoire de Biologie et de Modélisation de la Cellule (LBMC) CNRS/ENSL/UCBL, Ecole Normale Supérieure de Lyon, 69007 Lyon, France.
| | - Carlo Petosa
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, 38044 Grenoble, France.
| | - Stefan Dimitrov
- Institut for Advanced Biosciences, Inserm U 1209, CNRS UMR 5309, Université Grenoble Alpes, 38000 Grenoble, France.
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190
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Bilotti K, Kennedy EE, Li C, Delaney S. Human OGG1 activity in nucleosomes is facilitated by transient unwrapping of DNA and is influenced by the local histone environment. DNA Repair (Amst) 2017; 59:1-8. [PMID: 28892740 DOI: 10.1016/j.dnarep.2017.08.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 08/30/2017] [Accepted: 08/30/2017] [Indexed: 12/17/2022]
Abstract
If unrepaired, damage to genomic DNA can cause mutations and/or be cytotoxic. Single base lesions are repaired via the base excision repair (BER) pathway. The first step in BER is the recognition and removal of the nucleobase lesion by a glycosylase enzyme. For example, human oxoguanine glycosylase 1 (hOGG1) is responsible for removal of the prototypic oxidatively damaged nucleobase, 8-oxo-7,8-dihydroguanine (8-oxoG). To date, most studies of glycosylases have used free duplex DNA substrates. However, cellular DNA is packaged as repeating nucleosome units, with 145 base pair segments of DNA wrapped around histone protein octamers. Previous studies revealed inhibition of hOGG1 at the nucleosome dyad axis and in the absence of chromatin remodelers. In this study, we reveal that even in the absence of chromatin remodelers or external cofactors, hOGG1 can initiate BER at positions off the dyad axis and that this activity is facilitated by spontaneous and transient unwrapping of DNA from the histones. Additionally, we find that solution accessibility as determined by hydroxyl radical footprinting is not fully predictive of glycosylase activity and that histone tails can suppress hOGG1 activity. We therefore suggest that local nuances in the nucleosome environment and histone-DNA interactions can impact glycosylase activity.
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Affiliation(s)
- Katharina Bilotti
- Department of Chemistry, Brown University, Providence, RI 02912, United States
| | - Erin E Kennedy
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912, United States
| | - Chuxuan Li
- Department of Chemistry, Brown University, Providence, RI 02912, United States
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, RI 02912, United States.
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191
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Li F, Zhang Y, Bai J, Greenberg MM, Xi Z, Zhou C. 5-Formylcytosine Yields DNA-Protein Cross-Links in Nucleosome Core Particles. J Am Chem Soc 2017; 139:10617-10620. [PMID: 28742335 DOI: 10.1021/jacs.7b05495] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In situ generation of 5-formylcytosine (5fC) in nucleosome core particles (NCPs) reveals that 5fC leads to essential DNA-protein cross-links (DPCs). Mechanistic studies using chemical models and mutated histones demonstrate that DPCs form reversibly between the formyl function of 5fC and primary amines on histones. These results suggest that DPC formation from 5fC in chromatin occurs in addition to its role in DNA demethylation.
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Affiliation(s)
- Fengchao Li
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University , Tianjin 300071, China
| | - Yingqian Zhang
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University , Tianjin 300071, China
| | - Jing Bai
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University , Tianjin 300071, China
| | - Marc M Greenberg
- Department of Chemistry, Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Zhen Xi
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University , Tianjin 300071, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300071, China
| | - Chuanzheng Zhou
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University , Tianjin 300071, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300071, China
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192
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Berezhnoy NV, Liu Y, Allahverdi A, Yang R, Su CJ, Liu CF, Korolev N, Nordenskiöld L. The Influence of Ionic Environment and Histone Tails on Columnar Order of Nucleosome Core Particles. Biophys J 2017; 110:1720-1731. [PMID: 27119633 DOI: 10.1016/j.bpj.2016.03.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 02/04/2016] [Accepted: 03/07/2016] [Indexed: 01/08/2023] Open
Abstract
The nucleosome core particle (NCP) is the basic building block of chromatin. Nucleosome-nucleosome interactions are instrumental in chromatin compaction, and understanding NCP self-assembly is important for understanding chromatin structure and dynamics. Recombinant NCPs aggregated by multivalent cations form various ordered phases that can be studied by x-ray diffraction (small-angle x-ray scattering). In this work, the effects on the supramolecular structure of aggregated NCPs due to lysine histone H4 tail acetylations, histone H2A mutations (neutralizing the acidic patch of the histone octamer), and the removal of histone tails were investigated. The formation of ordered mainly hexagonal columnar NCP phases is in agreement with earlier studies; however, the highly homogeneous recombinant NCP systems used in this work display a more compact packing. The long-range order of the NCP columnar phase was found to be abolished or reduced by acetylation of the H4 tails, acidic patch neutralization, and removal of the H3 and H2B tails. Loss of nucleosome stacking upon removal of the H3 tails in combination with other tails was observed. In the absence of the H2A tails, the formation of an unknown highly ordered phase was observed.
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Affiliation(s)
- Nikolay V Berezhnoy
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Ying Liu
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Abdollah Allahverdi
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Renliang Yang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Chun-Jen Su
- National Synchrotron Radiation Research Center, Hsinchu, Taiwan
| | - Chuan-Fa Liu
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Nikolay Korolev
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
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193
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Calero-Cáceres W, Méndez J, Martín-Díaz J, Muniesa M. The occurrence of antibiotic resistance genes in a Mediterranean river and their persistence in the riverbed sediment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 223:384-394. [PMID: 28126386 DOI: 10.1016/j.envpol.2017.01.035] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/13/2017] [Accepted: 01/15/2017] [Indexed: 05/25/2023]
Abstract
The spread of antibiotic resistance genes (ARGs) in the environment is a serious concern. Bacterial ARGs can spread via different mobile genetic elements as phage particles, which thereby emerge as novel vectors for environmental dissemination. To assess how climate events, such as heavy rains or water scarcity, could affect the spread of ARGs, it is necessary to know their prevalence and abundance in aquatic environments as well as the potential reservoirs from which they could become mobile. This study evaluates the occurrence of ARGs in the water and sediment of a Mediterranean river. Six clinically relevant ARGs (blaTEM, blaCTX-M, qnrA, qnrS, mecA and sul1) were quantified by qPCR in the bacterial and phage fractions of 69 water and 70 sediment samples from the River Llobregat (NE Spain), collected during both dry and rainy periods. blaTEM and sul1 were the most prevalent and abundant ARGs; the others were more variable. Significant seasonal differences in ARG prevalences and abundances were observed. Since ARGs were detected in the sediment, the persistence of the most abundant ARGs naturally occurring in that sediment (blaTEM and sul1) was evaluated under three conditions. No ARG inactivation occurred in fresh sediment over 14 days; while the ARGs declined by less than 2 log10 units over 35 days in semi-dry and dry sediment. The occurrence of ARGs in water and sediment is influenced by seasonal conditions and they can be mobilized by bacteria and phage particles. In sediment, ARGs persist for long periods and hence sediment can be a natural reservoir of ARGs, from where they can spread and cause the emergence of new resistant strains.
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Affiliation(s)
- William Calero-Cáceres
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Diagonal 643, Annex, Floor 0, E-08028 Barcelona, Spain
| | - Javier Méndez
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Diagonal 643, Annex, Floor 0, E-08028 Barcelona, Spain
| | - Julia Martín-Díaz
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Diagonal 643, Annex, Floor 0, E-08028 Barcelona, Spain
| | - Maite Muniesa
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Diagonal 643, Annex, Floor 0, E-08028 Barcelona, Spain.
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194
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Olmon ED, Delaney S. Differential Ability of Five DNA Glycosylases to Recognize and Repair Damage on Nucleosomal DNA. ACS Chem Biol 2017; 12:692-701. [PMID: 28085251 DOI: 10.1021/acschembio.6b00921] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Damage to genomic DNA leads to mutagenesis and disease. Repair of single base damage is initiated by DNA glycosylases, the first enzymes in the base excision repair pathway. Although eukaryotic packaging of chromosomal DNA in nucleosomes is known to decrease DNA glycosylase efficiency, the impact on individual glycosylases is unclear. Here, we present a model system in which we examine the repair of site-specific base damage in well-characterized nucleosome core particles by five different DNA glycosylases. We find that DNA glycosylase efficiency on nucleosome substrates depends not only on the geometric orientation of the damaged base but also on its identity, as well as on the size, structure, and mechanism of the glycosylase. We show via molecular modeling that inhibition of glycosylase activity is largely due to steric obstruction by the nucleosome core.
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Affiliation(s)
- Eric D. Olmon
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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195
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Marze NA, Jeliazkov JR, Roy Burman SS, Boyken SE, DiMaio F, Gray JJ. Modeling oblong proteins and water-mediated interfaces with RosettaDock in CAPRI rounds 28-35. Proteins 2017; 85:479-486. [PMID: 27667482 PMCID: PMC5710743 DOI: 10.1002/prot.25168] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 09/01/2016] [Accepted: 09/26/2016] [Indexed: 12/27/2022]
Abstract
The 28th-35th rounds of the Critical Assessment of PRotein Interactions (CAPRI) served as a practical benchmark for our RosettaDock protein-protein docking protocols, highlighting strengths and weaknesses of the approach. We achieved acceptable or better quality models in three out of 11 targets. For the two α-repeat protein-green fluorescent protein (αrep-GFP) complexes, we used a novel ellipsoidal partial-global docking method (Ellipsoidal Dock) to generate models with 2.2 Å/1.5 Å interface RMSD, capturing 49%/42% of the native contacts, for the 7-/5-repeat αrep complexes. For the DNase-immunity protein complex, we used a new predictor of hydrogen-bonding networks, HBNet with Bridging Waters, to place individual water models at the complex interface; models were generated with 1.8 Å interface RMSD and 12% native water contacts recovered. The targets for which RosettaDock failed to create an acceptable model were typically difficult in general, as six had no acceptable models submitted by any CAPRI predictor. The UCH-L5-RPN13 and UCH-L5-INO80G de-ubiquitinating enzyme-inhibitor complexes comprised inhibitors undergoing significant structural changes upon binding, with the partners being highly interwoven in the docked complexes. Our failure to predict the nucleosome-enzyme complex in Target 95 was largely due to tight constraints we placed on our model based on sparse biochemical data suggesting two specific cross-interface interactions, preventing the correct structure from being sampled. While RosettaDock's three successes show that it is a state-of-the-art docking method, the difficulties with highly flexible and multi-domain complexes highlight the need for better flexible docking and domain-assembly methods. Proteins 2017; 85:479-486. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Nicholas A. Marze
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Jeliazko R. Jeliazkov
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland
- Program in Molecular Biophysics, Johns Hopkins University, Baltimore, Maryland
| | - Shourya S. Roy Burman
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Scott E. Boyken
- Department of Biochemistry, University of Washington, Seattle, Washington
- Institute for Protein Design, University of Washington, Seattle, Washington
| | - Frank DiMaio
- Department of Biochemistry, University of Washington, Seattle, Washington
- Institute for Protein Design, University of Washington, Seattle, Washington
| | - Jeffrey J. Gray
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
- Program in Molecular Biophysics, Johns Hopkins University, Baltimore, Maryland
- Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland
- Johns Hopkins School of Medicine, Sidney Kimmel Comprehensive Cancer Center, Baltimore, Maryland
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196
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Cannan WJ, Rashid I, Tomkinson AE, Wallace SS, Pederson DS. The Human Ligase IIIα-XRCC1 Protein Complex Performs DNA Nick Repair after Transient Unwrapping of Nucleosomal DNA. J Biol Chem 2017; 292:5227-5238. [PMID: 28184006 DOI: 10.1074/jbc.m116.736728] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 02/07/2017] [Indexed: 01/25/2023] Open
Abstract
Reactive oxygen species generate potentially cytotoxic and mutagenic lesions in DNA, both between and within the nucleosomes that package DNA in chromatin. The vast majority of these lesions are subject to base excision repair (BER). Enzymes that catalyze the first three steps in BER can act at many sites in nucleosomes without the aid of chromatin-remodeling agents and without irreversibly disrupting the host nucleosome. Here we show that the same is true for a protein complex comprising DNA ligase IIIα and the scaffolding protein X-ray repair cross-complementing protein 1 (XRCC1), which completes the fourth and final step in (short-patch) BER. Using in vitro assembled nucleosomes containing discretely positioned DNA nicks, our evidence indicates that the ligase IIIα-XRCC1 complex binds to DNA nicks in nucleosomes only when they are exposed by periodic, spontaneous partial unwrapping of DNA from the histone octamer; that the scaffolding protein XRCC1 enhances the ligation; that the ligation occurs within a complex that ligase IIIα-XRCC1 forms with the host nucleosome; and that the ligase IIIα-XRCC1-nucleosome complex decays when ligation is complete, allowing the host nucleosome to return to its native configuration. Taken together, our results illustrate ways in which dynamic properties intrinsic to nucleosomes may contribute to the discovery and efficient repair of base damage in chromatin.
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Affiliation(s)
- Wendy J Cannan
- From the Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, Vermont 05405 and
| | - Ishtiaque Rashid
- the University of New Mexico Cancer Center and Departments of Internal Medicine and Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, New Mexico 87131
| | - Alan E Tomkinson
- the University of New Mexico Cancer Center and Departments of Internal Medicine and Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, New Mexico 87131
| | - Susan S Wallace
- From the Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, Vermont 05405 and
| | - David S Pederson
- From the Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, Vermont 05405 and
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197
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Balliano A, Hao F, Njeri C, Balakrishnan L, Hayes JJ. HMGB1 Stimulates Activity of Polymerase β on Nucleosome Substrates. Biochemistry 2017; 56:647-656. [PMID: 28098985 PMCID: PMC5679249 DOI: 10.1021/acs.biochem.6b00569] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The process of base excision repair (BER) recognizes and repairs small lesions or inappropriate bases on DNA through either a short-patch or long-patch pathway. The enzymes involved in BER have been well-characterized on DNA substrates, and, somewhat surprisingly, many of these enzymes, including several DNA glycosylases, AP endonuclease (APE), FEN1 endonuclease, and DNA ligases, have been shown to have activity on DNA substrates within nucleosomes. DNA polymerase β (Pol β), however, exhibits drastically reduced or no activity on nucleosomal DNA. Interestingly, acetylation of Pol β, by the acetyltransferase p300, inhibits its 5' dRP-lyase activity and presumably pushes repair of DNA substrates through the long-patch base excision repair (LP-BER) pathway. In addition to the major enzymes involved in BER, a chromatin architectural factor, HMGB1, was found to directly interact with and enhance the activity of APE1 and FEN1, and thus may aid in altering the structure of the nucleosome to be more accessible to BER factors. In this work, we investigated whether acetylation of Pol β, either alone or in conjunction with HMGB1, facilitates its activity on nucleosome substrates. We find acetylated Pol β exhibits enhanced strand displacement synthesis activity on DNA substrates, but, similar to the unmodified enzyme, has little or no activity on nucleosomes. Preincubation of DNA templates with HMGB1 has little or no stimulatory effect on Pol β and even is inhibitory at higher concentrations. In contrast, preincubation of nucleosomes with HMGB1 rescues Pol β gap-filling activity in nucleosomes, suggesting that this factor may help overcome the repressive effects of chromatin.
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Affiliation(s)
- Angela Balliano
- Department of Biochemistry & Biophysics, University of Rochester Medical Center, Rochester, NY 14642
| | - Fanfan Hao
- Department of Biochemistry & Biophysics, University of Rochester Medical Center, Rochester, NY 14642
- Department of Biology, Indiana University Purdue University Indianapolis 723 W. Michigan St., Indianapolis, IN 46202-5132
| | - Catherine Njeri
- Department of Biology, Indiana University Purdue University Indianapolis 723 W. Michigan St., Indianapolis, IN 46202-5132
| | - Lata Balakrishnan
- Department of Biology, Indiana University Purdue University Indianapolis 723 W. Michigan St., Indianapolis, IN 46202-5132
| | - Jeffrey J. Hayes
- Department of Biochemistry & Biophysics, University of Rochester Medical Center, Rochester, NY 14642
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198
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Sultanov DC, Gerasimova NS, Kudryashova KS, Maluchenko NV, Kotova EY, Langelier MF, Pascal JM, Kirpichnikov MP, Feofanov AV, Studitsky VM. Unfolding of core nucleosomes by PARP-1 revealed by spFRET microscopy. AIMS GENETICS 2017; 4:21-31. [PMID: 28804761 PMCID: PMC5552189 DOI: 10.3934/genet.2017.1.21] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
DNA accessibility to various protein complexes is essential for various processes in the cell and is affected by nucleosome structure and dynamics. Protein factor PARP-1 (poly(ADP-ribose) polymerase 1) increases the accessibility of DNA in chromatin to repair proteins and transcriptional machinery, but the mechanism and extent of this chromatin reorganization are unknown. Here we report on the effects of PARP-1 on single nucleosomes revealed by spFRET (single-particle Förster Resonance Energy Transfer) microscopy. PARP-1 binding to a double-strand break in the vicinity of a nucleosome results in a significant increase of the distance between the adjacent gyres of nucleosomal DNA. This partial uncoiling of the entire nucleosomal DNA occurs without apparent loss of histones and is reversed after poly(ADP)-ribosylation of PARP-1. Thus PARP-1-nucleosome interactions result in reversible, partial uncoiling of the entire nucleosomal DNA.
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Affiliation(s)
- Daniel C Sultanov
- Biology Faculty, Lomonosov Moscow State University, Moscow, 119992, Russia.,Fox Chase Cancer Center, Philadelphia, PA, 19111-2497, USA
| | | | - Kseniya S Kudryashova
- Biology Faculty, Lomonosov Moscow State University, Moscow, 119992, Russia.,Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of Russian Academy of Sciences, 117997 Moscow, Russia
| | | | - Elena Y Kotova
- Fox Chase Cancer Center, Philadelphia, PA, 19111-2497, USA
| | - Marie-France Langelier
- Department of Biochemistry and Molecular Medicine, Université de Montréal, 2900 Boulevard Edouard-Montpetit, Montréal, QC H3T 1J4, Canada
| | - John M Pascal
- Department of Biochemistry and Molecular Medicine, Université de Montréal, 2900 Boulevard Edouard-Montpetit, Montréal, QC H3T 1J4, Canada
| | | | - Alexey V Feofanov
- Biology Faculty, Lomonosov Moscow State University, Moscow, 119992, Russia.,Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of Russian Academy of Sciences, 117997 Moscow, Russia
| | - Vasily M Studitsky
- Biology Faculty, Lomonosov Moscow State University, Moscow, 119992, Russia.,Fox Chase Cancer Center, Philadelphia, PA, 19111-2497, USA
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199
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Banerjee S, Chakraborty S, Jacinto MP, Paul MD, Balster MV, Greenberg MM. Probing Enhanced Double-Strand Break Formation at Abasic Sites within Clustered Lesions in Nucleosome Core Particles. Biochemistry 2016; 56:14-21. [PMID: 28005342 DOI: 10.1021/acs.biochem.6b01144] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
DNA is rapidly cleaved under mild alkaline conditions at apyrimidinic/apurinic sites, but the half-life is several weeks in phosphate buffer (pH 7.5). However, abasic sites are ∼100-fold more reactive within nucleosome core particles (NCPs). Histone proteins catalyze the strand scission, and at superhelical location 1.5, the histone H4 tail is largely responsible for the accelerated cleavage. The rate constant for strand scission at an abasic site is enhanced further in a nucleosome core particle when it is part of a bistranded lesion containing a proximal strand break. Cleavage of this form results in a highly deleterious double-strand break. This acceleration is dependent upon the position of the abasic lesion in the NCP and its structure. The enhancement in cleavage rate at an apurinic/apyrimidinic site rapidly drops off as the distance between the strand break and abasic site increases and is negligible once the two forms of damage are separated by 7 bp. However, the enhancement of the rate of double-strand break formation increases when the size of the gap is increased from one to two nucleotides. In contrast, the cleavage rate enhancement at 2-deoxyribonolactone within bistranded lesions is more modest, and it is similar in free DNA and nucleosome core particles. We postulate that the enhanced rate of double-strand break formation at bistranded lesions containing apurinic/apyrimidinic sites within nucleosome core particles is a general phenomenon and is due to increased DNA flexibility.
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Affiliation(s)
- Samya Banerjee
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Supratim Chakraborty
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Marco Paolo Jacinto
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Michael D Paul
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Morgan V Balster
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Marc M Greenberg
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
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200
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Todolli S, Perez PJ, Clauvelin N, Olson WK. Contributions of Sequence to the Higher-Order Structures of DNA. Biophys J 2016; 112:416-426. [PMID: 27955889 DOI: 10.1016/j.bpj.2016.11.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 11/11/2016] [Accepted: 11/15/2016] [Indexed: 11/17/2022] Open
Abstract
One of the critical unanswered questions in genome biophysics is how the primary sequence of DNA bases influences the global properties of very-long-chain molecules. The local sequence-dependent features of DNA found in high-resolution structures introduce irregularities in the disposition of adjacent residues that facilitate the specific binding of proteins and modulate the global folding and interactions of double helices with hundreds of basepairs. These features also determine the positions of nucleosomes on DNA and the lengths of the interspersed DNA linkers. Like the patterns of basepair association within DNA, the arrangements of nucleosomes in chromatin modulate the properties of longer polymers. The intrachromosomal loops detected in genomic studies contain hundreds of nucleosomes, and given that the simulated configurations of chromatin depend on the lengths of linker DNA, the formation of these loops may reflect sequence-dependent information encoded within the positioning of the nucleosomes. With knowledge of the positions of nucleosomes on a given genome, methods are now at hand to estimate the looping propensities of chromatin in terms of the spacing of nucleosomes and to make a direct connection between the DNA base sequence and larger-scale chromatin folding.
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Affiliation(s)
- Stefjord Todolli
- Center for Quantitative Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey
| | - Pamela J Perez
- Center for Quantitative Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey
| | - Nicolas Clauvelin
- Center for Quantitative Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey
| | - Wilma K Olson
- Department of Chemistry and Chemical Biology, The State University of New Jersey, Piscataway, New Jersey; Center for Quantitative Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey.
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