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Kariyawasam NL, Wereszczynski J. The Influence of Ionic Environment on Nucleosome-Mica Interactions Revealed via Molecular Dynamics Simulations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.25.600666. [PMID: 38979319 PMCID: PMC11230366 DOI: 10.1101/2024.06.25.600666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Mica serves as a crucial substrate in Atomic Force Microscopy (AFM) studies for visualizing and characterizing nucleosomes. Nucleosomes interact with the negatively charged mica surface via adsorbed cations. However, the specific influences of monovalent and divalent cations on nucleosome adsorption to the mica surface remain unclear. In this study, we investigated the binding of nucleosomes to the mica surface in the presence of monovalent potassium ions and divalent magnesium ions using molecular dynamics simulations. We also explored the impact of pre-treated mica surfaces on nucleosome binding and structure. Our findings reveal that nucleosome-mica interactions vary depending on the cations present, resulting in distinct effects on nucleosome structure. Notably, nucleosomes bind effectively to a mica surface in the presence of potassium ions with minimal structural perturbations.
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Affiliation(s)
- Nilusha L Kariyawasam
- Department of Physics, Illinois Institute of Technology, Chicago, USA
- Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, USA
| | - Jeff Wereszczynski
- Departments of Physics and Biology, Illinois Institute of Technology, Chicago, USA
- Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, USA
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2
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Dhahri H, Saintilnord WN, Chandler D, Fondufe-Mittendorf YN. Beyond the Usual Suspects: Examining the Role of Understudied Histone Variants in Breast Cancer. Int J Mol Sci 2024; 25:6788. [PMID: 38928493 PMCID: PMC11203562 DOI: 10.3390/ijms25126788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 06/13/2024] [Accepted: 06/18/2024] [Indexed: 06/28/2024] Open
Abstract
The incorporation of histone variants has structural ramifications on nucleosome dynamics and stability. Due to their unique sequences, histone variants can alter histone-histone or histone-DNA interactions, impacting the folding of DNA around the histone octamer and the overall higher-order structure of chromatin fibers. These structural modifications alter chromatin compaction and accessibility of DNA by transcription factors and other regulatory proteins to influence gene regulatory processes such as DNA damage and repair, as well as transcriptional activation or repression. Histone variants can also generate a unique interactome composed of histone chaperones and chromatin remodeling complexes. Any of these perturbations can contribute to cellular plasticity and the progression of human diseases. Here, we focus on a frequently overlooked group of histone variants lying within the four human histone gene clusters and their contribution to breast cancer.
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Affiliation(s)
- Hejer Dhahri
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA or (H.D.); (W.N.S.)
- Department of Epigenetics, Van Andel Research Institute, Grand Rapids, MI 49503, USA;
| | - Wesley N. Saintilnord
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA or (H.D.); (W.N.S.)
- Department of Epigenetics, Van Andel Research Institute, Grand Rapids, MI 49503, USA;
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, USA
- The Edison Family Center of Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Darrell Chandler
- Department of Epigenetics, Van Andel Research Institute, Grand Rapids, MI 49503, USA;
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3
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Khatua P, Tang PK, Moulick AG, Patel R, Manandhar A, Loverde SM. Sequence Dependence in Nucleosome Dynamics. J Phys Chem B 2024; 128:3090-3101. [PMID: 38530903 PMCID: PMC11181342 DOI: 10.1021/acs.jpcb.3c07363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
The basic packaging unit of eukaryotic chromatin is the nucleosome that contains 145-147 base pair duplex DNA wrapped around an octameric histone protein. While the DNA sequence plays a crucial role in controlling the positioning of the nucleosome, the molecular details behind the interplay between DNA sequence and nucleosome dynamics remain relatively unexplored. This study analyzes this interplay in detail by performing all-atom molecular dynamics simulations of nucleosomes, comparing the human α-satellite palindromic (ASP) and the strong positioning "Widom-601" DNA sequence at time scales of 12 μs. The simulations are performed at salt concentrations 10-20 times higher than physiological salt concentrations to screen the electrostatic interactions and promote unwrapping. These microsecond-long simulations give insight into the molecular-level sequence-dependent events that dictate the pathway of DNA unwrapping. We find that the "ASP" sequence forms a loop around SHL ± 5 for three sets of simulations. Coincident with loop formation is a cooperative increase in contacts with the neighboring N-terminal H2B tail and C-terminal H2A tail and the release of neighboring counterions. We find that the Widom-601 sequence exhibits a strong breathing motion of the nucleic acid ends. Coincident with the breathing motion is the collapse of the full N-terminal H3 tail and formation of an α-helix that interacts with the H3 histone core. We postulate that the dynamics of these histone tails and their modification with post-translational modifications (PTMs) may play a key role in governing this dynamics.
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Affiliation(s)
- Prabir Khatua
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York, 10314, United States
- Present Address: Department of Chemistry, GITAM School of Science, GITAM (Deemed to be University), Bengaluru, 562163, INDIA
| | - Phu K. Tang
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York, 10314, United States
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, NY, 10016, United States
- Present Address: Flatiron Institute, New York, NY, 10010, United States
- These authors contributed equally: Phu K. Tang, Abhik Ghosh Moulick, and Rutika Patel
| | - Abhik Ghosh Moulick
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York, 10314, United States
- These authors contributed equally: Phu K. Tang, Abhik Ghosh Moulick, and Rutika Patel
| | - Rutika Patel
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York, 10314, United States
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, NY, 10016, United States
- These authors contributed equally: Phu K. Tang, Abhik Ghosh Moulick, and Rutika Patel
| | - Anjela Manandhar
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York, 10314, United States
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, NY, 10016, United States
- Present Address: Takeda Pharmaceuticals, Boston, MA, 02139, United States
| | - Sharon M. Loverde
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York, 10314, United States
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, NY, 10016, United States
- Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, NY, 10016, United States
- Ph.D. Program in Physics, The Graduate Center of the City University of New York, New York, NY, 10016, United States
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4
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Li S, Wei T, Panchenko AR. Histone variant H2A.Z modulates nucleosome dynamics to promote DNA accessibility. Nat Commun 2023; 14:769. [PMID: 36765119 PMCID: PMC9918499 DOI: 10.1038/s41467-023-36465-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 02/02/2023] [Indexed: 02/12/2023] Open
Abstract
Nucleosomes, containing histone variants H2A.Z, are important for gene transcription initiation and termination, chromosome segregation and DNA double-strand break repair, among other functions. However, the underlying mechanisms of how H2A.Z influences nucleosome stability, dynamics and DNA accessibility are not well understood, as experimental and computational evidence remains inconclusive. Our modeling efforts of human nucleosome stability and dynamics, along with comparisons with experimental data show that the incorporation of H2A.Z results in a substantial decrease of the energy barrier for DNA unwrapping. This leads to the spontaneous DNA unwrapping of about forty base pairs from both ends, nucleosome gapping and increased histone plasticity, which otherwise is not observed for canonical nucleosomes. We demonstrate that both N- and C-terminal tails of H2A.Z play major roles in these events, whereas the H3.3 variant exerts a negligible impact in modulating the DNA end unwrapping. In summary, our results indicate that H2A.Z deposition makes nucleosomes more mobile and DNA more accessible to transcriptional machinery and other chromatin components.
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Affiliation(s)
- Shuxiang Li
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada
| | - Tiejun Wei
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada. .,Department of Biology and Molecular Sciences, Queen's University, Kingston, ON, Canada. .,School of Computing, Queen's University, Kingston, ON, Canada. .,Ontario Institute of Cancer Research, Toronto, Canada.
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5
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Krajewski WA. Histone Modifications, Internucleosome Dynamics, and DNA Stresses: How They Cooperate to “Functionalize” Nucleosomes. Front Genet 2022; 13:873398. [PMID: 35571051 PMCID: PMC9096104 DOI: 10.3389/fgene.2022.873398] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/28/2022] [Indexed: 12/25/2022] Open
Abstract
Tight packaging of DNA in chromatin severely constrains DNA accessibility and dynamics. In contrast, nucleosomes in active chromatin state are highly flexible, can exchange their histones, and are virtually “transparent” to RNA polymerases, which transcribe through gene bodies at rates comparable to that of naked DNA. Defining mechanisms that revert nucleosome repression, in addition to their value for basic science, is of key importance for the diagnosis and treatment of genetic diseases. Chromatin activity is largely regulated by histone posttranslational modifications, ranging from small chemical groups up to the yet understudied “bulky” ubiquitylation and sumoylation. However, it is to be revealed how histone marks are “translated” to permissive or repressive changes in nucleosomes: it is a general opinion that histone modifications act primarily as “signals” for recruiting the regulatory proteins or as a “neutralizer” of electrostatic shielding of histone tails. Here, we would like to discuss recent evidence suggesting that histone ubiquitylation, in a DNA stress–dependent manner, can directly regulate the dynamics of the nucleosome and their primary structure and can promote nucleosome decomposition to hexasome particles or additionally stabilize nucleosomes against unwrapping. In addition, nucleosome repression/ derepression studies are usually performed with single mononucleosomes as a model. We would like to review and discuss recent findings showing that internucleosomal interactions could strongly modulate the dynamics and rearrangements of nucleosomes. Our hypothesis is that bulky histone modifications, nucleosome inherent dynamics, internucleosome interactions, and DNA torsions could act in cooperation to orchestrate the formation of different dynamic states of arrayed nucleosomes and thus promote chromatin functionality and diversify epigenetic programming methods.
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6
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Peng Y, Li S, Onufriev A, Landsman D, Panchenko AR. Binding of regulatory proteins to nucleosomes is modulated by dynamic histone tails. Nat Commun 2021; 12:5280. [PMID: 34489435 PMCID: PMC8421395 DOI: 10.1038/s41467-021-25568-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 08/17/2021] [Indexed: 12/19/2022] Open
Abstract
Little is known about the roles of histone tails in modulating nucleosomal DNA accessibility and its recognition by other macromolecules. Here we generate extensive atomic level conformational ensembles of histone tails in the context of the full nucleosome, totaling 65 microseconds of molecular dynamics simulations. We observe rapid conformational transitions between tail bound and unbound states, and characterize kinetic and thermodynamic properties of histone tail-DNA interactions. Different histone types exhibit distinct binding modes to specific DNA regions. Using a comprehensive set of experimental nucleosome complexes, we find that the majority of them target mutually exclusive regions with histone tails on nucleosomal/linker DNA around the super-helical locations ± 1, ± 2, and ± 7, and histone tails H3 and H4 contribute most to this process. These findings are explained within competitive binding and tail displacement models. Finally, we demonstrate the crosstalk between different histone tail post-translational modifications and mutations; those which change charge, suppress tail-DNA interactions and enhance histone tail dynamics and DNA accessibility. The intrinsic disorder of histone tails poses challenges in their characterization. Here the authors apply extensive molecular dynamics simulations of the full nucleosome to show reversible binding to DNA with specific binding modes of different types of histone tails, where charge-altering modifications suppress tail-DNA interactions and may boost interactions between nucleosomes and nucleosome-binding proteins.
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Affiliation(s)
- Yunhui Peng
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD, USA
| | - Shuxiang Li
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, ON, Canada
| | - Alexey Onufriev
- Physics Department, Virginia Tech, VA, USA.,Computer Science Department, Virginia Tech, VA, USA.,Center for Soft Matter and Biological Physics, Virginia Tech, VA, USA
| | - David Landsman
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD, USA
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, ON, Canada.
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7
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Torsional stress can regulate the unwrapping of two outer half superhelical turns of nucleosomal DNA. Proc Natl Acad Sci U S A 2021; 118:2020452118. [PMID: 33558240 DOI: 10.1073/pnas.2020452118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Torsional stress has a significant impact on the structure and stability of the nucleosome. RNA polymerase imposes torsional stress on the DNA in chromatin and unwraps the DNA from the nucleosome to access the genetic information encoded in the DNA. To understand how the torsional stress affects the stability of the nucleosome, we examined the unwrapping of two half superhelical turns of nucleosomal DNA from either end of the DNA under torsional stress with all-atom molecular dynamics simulations. The free energies for unwrapping the DNA indicate that positive stress that overtwists DNA facilitates a large-scale asymmetric unwrapping of the DNA without a large extension of the DNA. During the unwrapping, one end of the DNA was dissociated from H3 and H2A-H2B, while the other end of the DNA stably remained wrapped. The detailed analysis indicates that this asymmetric dissociation is facilitated by the geometry and bendability of the DNA under positive stress. The geometry stabilized the interaction between the major groove of the twisted DNA and the H3 αN-helix, and the straightened DNA destabilized the interaction with H2A-H2B. Under negative stress, the DNA became more bendable and flexible, which facilitated the binding of the unwrapped DNA to the octamer in a stable state. Consequently, we conclude that the torsional stress has a significant impact on the affinity of the DNA and the octamer through the inherent nature of the DNA and can change the accessibility of regulatory proteins.
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8
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Peng Y, Li S, Landsman D, Panchenko AR. Histone tails as signaling antennas of chromatin. Curr Opin Struct Biol 2021; 67:153-160. [PMID: 33279866 PMCID: PMC8096652 DOI: 10.1016/j.sbi.2020.10.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 10/07/2020] [Accepted: 10/18/2020] [Indexed: 12/19/2022]
Abstract
Histone tails, representing the N-terminal or C-terminal regions flanking the histone core, play essential roles in chromatin signaling networks. Intrinsic disorder of histone tails and their propensity for post-translational modifications allow them to serve as hubs in coordination of epigenetic processes within the nucleosomal context. Deposition of histone variants with distinct histone tail properties further enriches histone tails' repertoire in epigenetic signaling. Given the advances in experimental techniques and in silico modelling, we review the most recent data on histone tails' effects on nucleosome stability and dynamics, their function in regulating chromatin accessibility and folding. Finally, we discuss different molecular mechanisms to understand how histone tails are involved in nucleosome recognition by binding partners and formation of higher-order chromatin structures.
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Affiliation(s)
- Yunhui Peng
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD, USA
| | - Shuxiang Li
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, ON, Canada
| | - David Landsman
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD, USA
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, ON, Canada.
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9
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Huertas J, Cojocaru V. Breaths, Twists, and Turns of Atomistic Nucleosomes. J Mol Biol 2020; 433:166744. [PMID: 33309853 DOI: 10.1016/j.jmb.2020.166744] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 12/02/2020] [Accepted: 12/02/2020] [Indexed: 02/07/2023]
Abstract
Gene regulation programs establish cellular identity and rely on dynamic changes in the structural packaging of genomic DNA. The DNA is packaged in chromatin, which is formed from arrays of nucleosomes displaying different degree of compaction and different lengths of inter-nucleosomal linker DNA. The nucleosome represents the repetitive unit of chromatin and is formed by wrapping 145-147 basepairs of DNA around an octamer of histone proteins. Each of the four histones is present twice and has a structured core and intrinsically disordered terminal tails. Chromatin dynamics are triggered by inter- and intra-nucleosome motions that are controlled by the DNA sequence, the interactions between the histone core and the DNA, and the conformations, positions, and DNA interactions of the histone tails. Understanding chromatin dynamics requires studying all these features at the highest possible resolution. For this, molecular dynamics simulations can be used as a powerful complement or alternative to experimental approaches, from which it is often very challenging to characterize the structural features and atomic interactions controlling nucleosome motions. Molecular dynamics simulations can be performed at different resolutions, by coarse graining the molecular system with varying levels of details. Here we review the successes and the remaining challenges of the application of atomic resolution simulations to study the structure and dynamics of nucleosomes and their complexes with interacting partners.
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Affiliation(s)
- Jan Huertas
- In Silico Biomolecular Structure and Dynamics Group, Hubrecht Institute, Utrecht, the Netherlands; Department of Cellular and Developmental Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany; Center for Multiscale Theory and Computation, Westfälische Wilhelms University, Münster, Germany
| | - Vlad Cojocaru
- In Silico Biomolecular Structure and Dynamics Group, Hubrecht Institute, Utrecht, the Netherlands; Department of Cellular and Developmental Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany; Center for Multiscale Theory and Computation, Westfälische Wilhelms University, Münster, Germany.
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10
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Kono H, Ishida H. Nucleosome unwrapping and unstacking. Curr Opin Struct Biol 2020; 64:119-125. [DOI: 10.1016/j.sbi.2020.06.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 05/31/2020] [Accepted: 06/23/2020] [Indexed: 02/07/2023]
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11
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Krajewski WA. "Direct" and "Indirect" Effects of Histone Modifications: Modulation of Sterical Bulk as a Novel Source of Functionality. Bioessays 2019; 42:e1900136. [PMID: 31805213 DOI: 10.1002/bies.201900136] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/17/2019] [Indexed: 12/26/2022]
Abstract
The chromatin-regulatory principles of histone post-translational modifications (PTMs) are discussed with a focus on the potential alterations in chromatin functional state due to steric and mechanical constraints imposed by bulky histone modifications such as ubiquitin and SUMO. In the classical view, PTMs operate as recruitment platforms for histone "readers," and as determinants of chromatin array compaction. Alterations of histone charges by "small" chemical modifications (e.g., acetylation, phosphorylation) could regulate nucleosome spontaneous dynamics without globally affecting nucleosome structure. These fluctuations in nucleosome wrapping can be exploited by chromatin-processing machinery. In contrast, ubiquitin and SUMO are comparable in size to histones, and it seems logical that these PTMs could conflict with canonical nucleosome organization. An experimentally testable hypothesis that by adding sterical bulk these PTMs can robustly alter nucleosome primary structure is proposed. The model presented here stresses the diversity of mechanisms by which histone PTMs regulate chromatin dynamics, primary structure and, hence, functionality.
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Affiliation(s)
- Wladyslaw A Krajewski
- N. K. Koltsov Institute of Developmental Biology of Russian Academy of Sciences, Vavilova str. 26, Moscow, 119334, Russia
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12
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Parsons T, Zhang B. Critical role of histone tail entropy in nucleosome unwinding. J Chem Phys 2019; 150:185103. [PMID: 31091895 DOI: 10.1063/1.5085663] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The nucleosome is the fundamental packaging unit for the genome. It must remain tightly wound to ensure genome stability while simultaneously being flexible enough to keep the DNA molecule accessible for genome function. The set of physicochemical interactions responsible for the delicate balance between these naturally opposed processes have not been determined due to challenges in resolving partially unwound nucleosome configurations at atomic resolution. Using a near atomistic protein-DNA model and advanced sampling techniques, we calculate the free energy cost of nucleosome DNA unwinding. Our simulations identify a large energetic barrier that decouples the outer and the inner DNA unwinding into two separate processes, occurring on different time scales. This dynamical decoupling allows the exposure of outer DNA at a modest cost to ensure accessibility while keeping the inner DNA and the histone core intact to maintain stability. We also reveal that this energetic barrier arises from a delayed loss of contacts between disordered histone tails and the DNA and is, surprisingly, largely offset by an entropic contribution from these tails. Implications of this enthalpy entropy compensation for the regulation of nucleosome stability and genome function are discussed.
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Affiliation(s)
- Thomas Parsons
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA
| | - Bin Zhang
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA
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13
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Chakraborty K, Kang M, Loverde SM. Molecular Mechanism for the Role of the H2A and H2B Histone Tails in Nucleosome Repositioning. J Phys Chem B 2018; 122:11827-11840. [DOI: 10.1021/acs.jpcb.8b07881] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kaushik Chakraborty
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York 10314, United States
| | - Myungshim Kang
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York 10314, United States
| | - Sharon M. Loverde
- Department of Chemistry, College of Staten Island, The City University of New York, 2800 Victory Boulevard, Staten Island, New York 10314, United States
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14
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Morrison EA, Bowerman S, Sylvers KL, Wereszczynski J, Musselman CA. The conformation of the histone H3 tail inhibits association of the BPTF PHD finger with the nucleosome. eLife 2018; 7:31481. [PMID: 29648537 PMCID: PMC5953545 DOI: 10.7554/elife.31481] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 04/11/2018] [Indexed: 01/08/2023] Open
Abstract
Histone tails harbor a plethora of post-translational modifications that direct the function of chromatin regulators, which recognize them through effector domains. Effector domain/histone interactions have been broadly studied, but largely using peptide fragments of histone tails. Here, we extend these studies into the nucleosome context and find that the conformation adopted by the histone H3 tails is inhibitory to BPTF PHD finger binding. Using NMR spectroscopy and MD simulations, we show that the H3 tails interact robustly but dynamically with nucleosomal DNA, substantially reducing PHD finger association. Altering the electrostatics of the H3 tail via modification or mutation increases accessibility to the PHD finger, indicating that PTM crosstalk can regulate effector domain binding by altering nucleosome conformation. Together, our results demonstrate that the nucleosome context has a dramatic impact on signaling events at the histone tails, and highlights the importance of studying histone binding in the context of the nucleosome.
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Affiliation(s)
- Emma A Morrison
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, United States
| | - Samuel Bowerman
- Department of Physics, Illinois Institute of Technology, Chicago, Illinois.,Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, Illinois
| | - Kelli L Sylvers
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, United States
| | - Jeff Wereszczynski
- Department of Physics, Illinois Institute of Technology, Chicago, Illinois.,Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, Illinois
| | - Catherine A Musselman
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, United States
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