1
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van Heesch T, van de Lagemaat EM, Vreede J. Deciphering Sequence-Specific DNA Binding by H-NS Using Molecular Simulation. Methods Mol Biol 2024; 2819:585-609. [PMID: 39028525 DOI: 10.1007/978-1-0716-3930-6_27] [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] [Indexed: 07/20/2024]
Abstract
H-NS is a DNA organizing protein that occurs in Gram-negative bacteria. It can form long filaments between two DNA duplexes by first binding to a high-affinity AT-rich nucleotide sequence and extending from there. Using molecular dynamics simulations and steered molecular dynamics, we are able to determine the free energy of formation and dissociation of a protein-DNA complex comprising an H-NS DNA-binding domain and a specific nucleotide sequence. The molecular dynamics simulations allow detailed characterization of the interactions between the protein and a specific nucleotide sequence. To quantify the strength of the interaction, we employ an additional potential based on protein-DNA contacts to speed up dissociation of the protein-DNA complex. The work required for the dissociation results in an estimate of the free energy of dissociation/complex formation. Our protocol can provide quantitative prediction of protein-DNA complex stability, while also providing high-resolution insights into recognition mechanisms. In this chapter, we have used this approach to quantify the sequence specificity of H-NS DNA-binding domains to various nucleotide sequences, thus elucidating the mechanism with which H-NS can specifically bind to AT-rich DNA.
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Affiliation(s)
- Thor van Heesch
- van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Eline M van de Lagemaat
- van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Jocelyne Vreede
- van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands.
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2
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Alston JJ, Soranno A. Condensation Goes Viral: A Polymer Physics Perspective. J Mol Biol 2023; 435:167988. [PMID: 36709795 PMCID: PMC10368797 DOI: 10.1016/j.jmb.2023.167988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023]
Abstract
The past decade has seen a revolution in our understanding of how the cellular environment is organized, where an incredible body of work has provided new insights into the role played by membraneless organelles. These rapid advancements have been made possible by an increasing awareness of the peculiar physical properties that give rise to such bodies and the complex biology that enables their function. Viral infections are not extraneous to this. Indeed, in host cells, viruses can harness existing membraneless compartments or, even, induce the formation of new ones. By hijacking the cellular machinery, these intracellular bodies can assist in the replication, assembly, and packaging of the viral genome as well as in the escape of the cellular immune response. Here, we provide a perspective on the fundamental polymer physics concepts that may help connect and interpret the different observed phenomena, ranging from the condensation of viral genomes to the phase separation of multicomponent solutions. We complement the discussion of the physical basis with a description of biophysical methods that can provide quantitative insights for testing and developing theoretical and computational models.
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Affiliation(s)
- Jhullian J Alston
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 St Euclid Ave, 63110 Saint Louis, MO, USA; Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130 Saint Louis, MO, USA
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 St Euclid Ave, 63110 Saint Louis, MO, USA; Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130 Saint Louis, MO, USA.
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3
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Mu ZC, Tan YL, Liu J, Zhang BG, Shi YZ. Computational Modeling of DNA 3D Structures: From Dynamics and Mechanics to Folding. Molecules 2023; 28:4833. [PMID: 37375388 DOI: 10.3390/molecules28124833] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/11/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
DNA carries the genetic information required for the synthesis of RNA and proteins and plays an important role in many processes of biological development. Understanding the three-dimensional (3D) structures and dynamics of DNA is crucial for understanding their biological functions and guiding the development of novel materials. In this review, we discuss the recent advancements in computer methods for studying DNA 3D structures. This includes molecular dynamics simulations to analyze DNA dynamics, flexibility, and ion binding. We also explore various coarse-grained models used for DNA structure prediction or folding, along with fragment assembly methods for constructing DNA 3D structures. Furthermore, we also discuss the advantages and disadvantages of these methods and highlight their differences.
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Affiliation(s)
- Zi-Chun Mu
- Research Center of Nonlinear Science, School of Mathematical & Physical Sciences, Wuhan Textile University, Wuhan 430073, China
- School of Computer Science and Artificial Intelligence, Wuhan Textile University, Wuhan 430073, China
| | - Ya-Lan Tan
- Research Center of Nonlinear Science, School of Mathematical & Physical Sciences, Wuhan Textile University, Wuhan 430073, China
| | - Jie Liu
- Research Center of Nonlinear Science, School of Mathematical & Physical Sciences, Wuhan Textile University, Wuhan 430073, China
| | - Ben-Gong Zhang
- Research Center of Nonlinear Science, School of Mathematical & Physical Sciences, Wuhan Textile University, Wuhan 430073, China
| | - Ya-Zhou Shi
- Research Center of Nonlinear Science, School of Mathematical & Physical Sciences, Wuhan Textile University, Wuhan 430073, China
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4
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Zhang Z, Šponer J, Bussi G, Mlýnský V, Šulc P, Simmons CR, Stephanopoulos N, Krepl M. Atomistic Picture of Opening-Closing Dynamics of DNA Holliday Junction Obtained by Molecular Simulations. J Chem Inf Model 2023; 63:2794-2809. [PMID: 37126365 PMCID: PMC10170514 DOI: 10.1021/acs.jcim.3c00358] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Holliday junction (HJ) is a noncanonical four-way DNA structure with a prominent role in DNA repair, recombination, and DNA nanotechnology. By rearranging its four arms, HJ can adopt either closed or open state. With enzymes typically recognizing only a single state, acquiring detailed knowledge of the rearrangement process is an important step toward fully understanding the biological function of HJs. Here, we carried out standard all-atom molecular dynamics (MD) simulations of the spontaneous opening-closing transitions, which revealed complex conformational transitions of HJs with an involvement of previously unconsidered "half-closed" intermediates. Detailed free-energy landscapes of the transitions were obtained by sophisticated enhanced sampling simulations. Because the force field overstabilizes the closed conformation of HJs, we developed a system-specific modification which for the first time allows the observation of spontaneous opening-closing HJ transitions in unbiased MD simulations and opens the possibilities for more accurate HJ computational studies of biological processes and nanomaterials.
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Affiliation(s)
- Zhengyue Zhang
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 00 Brno, Czech Republic
- CEITEC─Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
- National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 00 Brno, Czech Republic
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), via Bonomea 265, 34136 Trieste, Italy
| | - Vojtěch Mlýnský
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 00 Brno, Czech Republic
| | - Petr Šulc
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University, 1001 S. McAllister Ave, Tempe, 85287 Arizona, United States
| | - Chad R Simmons
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University, 1001 S. McAllister Ave, Tempe, 85287 Arizona, United States
| | - Nicholas Stephanopoulos
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University, 1001 S. McAllister Ave, Tempe, 85287 Arizona, United States
| | - Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 00 Brno, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute (CATRIN), Palacky University Olomouc, Slechtitelu 241/27, 783 71 Olomouc, Czech Republic
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5
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Olson WK, Li Y, Fenley MO. Insights into DNA solvation found in protein-DNA structures. Biophys J 2022; 121:4749-4758. [PMID: 36380591 PMCID: PMC9808563 DOI: 10.1016/j.bpj.2022.11.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/31/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022] Open
Abstract
The proteins that bind double-helical DNA present various microenvironments that sense and/or induce signals in the genetic material. The high-resolution structures of protein-DNA complexes reveal the nature of both the microenvironments and the conformational responses in DNA and protein. Complex networks of interactions within the structures somehow tie the protein and DNA together and induce the observed spatial forms. Here we show how the cumulative buildup of amino acid atoms around the sugars, phosphates, and bases in different protein-DNA complexes produces a binding cloud around the double helix and how different types of atoms fill that cloud. Rather than focusing on the principles of molecular binding and recognition suggested by the arrangements of amino acids and nucleotides in the macromolecular complexes, we consider the proteins in contact with DNA as organized solvents. We describe differences in the mix of atoms that come in closest contact with DNA, subtle sequence-dependent features in the microenvironment of the sugar-phosphate backbone, a direct link between the localized buildup of ionic species and the electrostatic potential surfaces of the DNA bases, and sites of atomic buildup above and below the basepair planes that transmit the unique features of the base environments along the chain backbone. The inferences about solvation that can be drawn from the survey provide new stimuli for improvement of nucleic acid force fields and fresh ideas for exploration of the properties of DNA in solution.
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Affiliation(s)
- Wilma K Olson
- Department of Chemistry and Chemical Biology and Center for Quantitative Biology, Rutgers, the State University of New Jersey, Piscataway, New Jersey.
| | - Yun Li
- Department of Chemistry and Chemical Biology and Center for Quantitative Biology, Rutgers, the State University of New Jersey, Piscataway, New Jersey
| | - Marcia O Fenley
- Department of Chemistry and Chemical Biology and Center for Quantitative Biology, Rutgers, the State University of New Jersey, Piscataway, New Jersey; Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida
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6
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Patra P, Gao YQ. Sequence-Specific Structural Features and Solvation Properties of Transcription Factor Binding DNA Motifs: Insights from Molecular Dynamics Simulation. J Phys Chem B 2022; 126:9187-9206. [PMID: 36322688 DOI: 10.1021/acs.jpcb.2c05749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Sequence-specific recognition of transcription factor (TF) binding motifs in the target site of DNA over the vast amount of non-target DNA is of primary importance for the transcriptional regulation of gene expression by the TFs. Binding of TFs to the target site of DNA relies not only on the direct contact formation but also on the structural and conformational features of DNA. Recognition of DNA structural features or shape readout by proteins is an important factor in the context of TF-DNA interaction. Based on the atomistic molecular simulation, here we report the sequence-dependent unique structural features, solvation, and ion-binding properties of biologically relevant AT- and GC-rich human TF binding motifs in DNA. Counterion and water distribution around the motif is found to be sensitive to the motif sequence, which is accompanied with the DNA shape features. The motif sequence affects the electrostatic potential along the grooves, and cytosine methylation alters the DNA shape features. Characteristic solvation properties of TF binding motif DNA fragments infer that an ionic environment and hydration influences are essential to describe TF-DNA interactions.
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Affiliation(s)
- Piya Patra
- Shenzhen Bay Laboratory, Institute of Systems and Physical Biology, Shenzhen 518107, China
| | - Yi Qin Gao
- Shenzhen Bay Laboratory, Institute of Systems and Physical Biology, Shenzhen 518107, China.,Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.,Biomedical Pioneering Innovation Center, Peking University, Beijing 100871, China
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7
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Cruz-León S, Schwierz N. RNA Captures More Cations than DNA: Insights from Molecular Dynamics Simulations. J Phys Chem B 2022; 126:8646-8654. [PMID: 36260822 PMCID: PMC9639116 DOI: 10.1021/acs.jpcb.2c04488] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The distribution of cations around nucleic acids is essential for a broad variety of processes ranging from DNA condensation and RNA folding to the detection of biomolecules in biosensors. Predicting the exact distribution of ions remains challenging since the distribution and, hence, a broad variety of nucleic acid properties depend on the salt concentration, the valency of the ions, and the ion type. Despite the importance, a general theory to quantify ion-specific effects for highly charged biomolecules is still lacking. Moreover, recent experiments reveal that despite their similar building blocks, DNA and RNA duplexes can react differently to the same ionic conditions. The aim of our current work is to provide a comprehensive set of molecular dynamics simulations using more than 180 μs of simulation time. For the mono- and divalent cations Li+, Na+, K+, Cs+, Ca2+, Sr2+, and Ba2+, the simulations allow us to reveal the ion-specific distributions and binding patterns for DNA and RNA duplexes. The microscopic insights from the simulations display the origin of ion-specificity and shed light on the question of why DNA and RNA show opposing behavior in the same ionic conditions. Finally, the detailed binding patterns from the simulations reveal why RNA can capture more cations than DNA.
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Affiliation(s)
- Sergio Cruz-León
- Department
of Theoretical Biophysics, Max Planck Institute
of Biophysics, Max-von-Laue-Str. 3, 60438Frankfurt am Main, Germany
| | - Nadine Schwierz
- Department
of Theoretical Biophysics, Max Planck Institute
of Biophysics, Max-von-Laue-Str. 3, 60438Frankfurt am Main, Germany,Institute
of Physics, University of Augsburg, Universitätsstraße 1, 86159Augsburg, Germany,E-mail:
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8
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Singh A, Maity A, Singh N. Structure and Dynamics of dsDNA in Cell-like Environments. ENTROPY (BASEL, SWITZERLAND) 2022; 24:1587. [PMID: 36359677 PMCID: PMC9689892 DOI: 10.3390/e24111587] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 10/28/2022] [Accepted: 10/31/2022] [Indexed: 06/01/2023]
Abstract
Deoxyribonucleic acid (DNA) is a fundamental biomolecule for correct cellular functioning and regulation of biological processes. DNA's structure is dynamic and has the ability to adopt a variety of structural conformations in addition to its most widely known double-stranded DNA (dsDNA) helix structure. Stability and structural dynamics of dsDNA play an important role in molecular biology. In vivo, DNA molecules are folded in a tightly confined space, such as a cell chamber or a channel, and are highly dense in solution; their conformational properties are restricted, which affects their thermodynamics and mechanical properties. There are also many technical medical purposes for which DNA is placed in a confined space, such as gene therapy, DNA encapsulation, DNA mapping, etc. Physiological conditions and the nature of confined spaces have a significant influence on the opening or denaturation of DNA base pairs. In this review, we summarize the progress of research on the stability and dynamics of dsDNA in cell-like environments and discuss current challenges and future directions. We include studies on various thermal and mechanical properties of dsDNA in ionic solutions, molecular crowded environments, and confined spaces. By providing a better understanding of melting and unzipping of dsDNA in different environments, this review provides valuable guidelines for predicting DNA thermodynamic quantities and for designing DNA/RNA nanostructures.
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9
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Ramachandran V, Mainan A, Roy S. Dynamic effects of the spine of hydrated magnesium on viral RNA pseudoknot structure. Phys Chem Chem Phys 2022; 24:24570-24581. [PMID: 36193826 DOI: 10.1039/d2cp01075e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
In the cellular environment, a viral RNA Pseudoknot (PK) structure is responsive to its prevailing ion atmosphere created by a mixture of monovalent and divalent cations. We investigate the influence of such a mixed-salt environment on RNA-PK structure at an atomic resolution through three sets of 1.5 μs explicit solvent molecular dynamics (MD) simulations and also by building a dynamic counterion-condensation (DCC) model at varying divalent Mg2+ concentrations. The DCC model includes explicit interaction of the ligand and adjacent chelated Mg2+ by extending the recently developed generalized Manning condensation model. Its implementation within an all-atom structure-based molecular dynamics framework bolsters its opportunity to explore large-length scale and long-timescale phenomena associated with complex RNA systems immersed in its dynamic ion environment. In the present case of RNA-PK, both explicit MD and DCC simulations reveal a spine of hydrated-Mg2+ to induce stem-I and stem-II closure where the minor groove between these stems is akin to breathing. Mg2+ mediated minor-groove narrowing is coupled with local base-flipping dynamics of a base triple and quadruple, changing the stem structure of such RNA. Contrary to the conversational view of the indispensable need for Mg2+ for the tertiary structure of RNA, the study warns about the plausible detrimental effect of specific Mg2+-phosphate interactions on the RNA-PK structure beyond a certain concentration of Mg2+.
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Affiliation(s)
- Vysakh Ramachandran
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
| | - Avijit Mainan
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
| | - Susmita Roy
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
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10
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Yu B, Bien KG, Wang T, Iwahara J. Diffusion NMR-based comparison of electrostatic influences of DNA on various monovalent cations. Biophys J 2022; 121:3562-3570. [PMID: 35754184 PMCID: PMC9515368 DOI: 10.1016/j.bpj.2022.06.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 06/03/2022] [Accepted: 06/22/2022] [Indexed: 11/18/2022] Open
Abstract
Counterions are important constituents for the structure and function of nucleic acids. Using 7Li and 133Cs nuclear magnetic resonance (NMR) spectroscopy, we investigated how ionic radii affect the behavior of counterions around DNA through diffusion measurements of Li+ and Cs+ ions around a 15-bp DNA duplex. Together with our previous data on 23Na+ and 15NH4+ ions around the same DNA under the same conditions, we were able to compare the dynamics of four different monovalent ions around DNA. From the apparent diffusion coefficients at varied concentrations of DNA, we determined the diffusion coefficients of these cations inside and outside the ion atmosphere around DNA (Db and Df, respectively). We also analyzed ionic competition with K+ ions for the ion atmosphere and assessed the relative affinities of these cations for DNA. Interestingly, all cations (i.e., Li+, Na+, NH4+, and Cs+) analyzed by diffusion NMR spectroscopy exhibited nearly identical Db/Df ratios despite the differences in their ionic radii, relative affinities, and diffusion coefficients. These results, along with the theoretical relationship between diffusion and entropy, suggest that the entropy change due to the release of counterions from the ion atmosphere around DNA is also similar regardless of the monovalent ion types. These findings and the experimental diffusion data on the monovalent ions are useful for examination of computational models for electrostatic interactions or ion solvation.
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Affiliation(s)
- Binhan Yu
- Department of Biochemistry & Molecular Biology, Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas
| | - Karina G Bien
- Department of Biochemistry & Molecular Biology, Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas
| | - Tianzhi Wang
- Department of Biochemistry & Molecular Biology, Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas
| | - Junji Iwahara
- Department of Biochemistry & Molecular Biology, Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas.
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11
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Abdelgawwad AMA, Monari A, Tuñón I, Francés-Monerris A. Spatial and Temporal Resolution of the Oxygen-Independent Photoinduced DNA Interstrand Cross-Linking by a Nitroimidazole Derivative. J Chem Inf Model 2022; 62:3239-3252. [PMID: 35771238 PMCID: PMC9277591 DOI: 10.1021/acs.jcim.2c00460] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
DNA damage is ubiquitous in nature and is at the basis of emergent treatments such as photodynamic therapy, which is based on the activation of highly oxidative reactive oxygen species by photosensitizing O2. However, hypoxia observed in solid tumors imposes the necessity to devise oxygen-independent modes of action able to induce DNA damage under a low oxygen concentration. The complexity of these DNA damage mechanisms in realistic environments grows exponentially when taking into account light absorption and subsequent excited-state population, photochemical and (photo)-redox reactions, the multiple species involved in different electronic states, noncovalent interactions, multiple reaction steps, and the large number of DNA reactive sites. This work tackles all the intricate reactivity of a photosensitizer based on a nitroimidazole derivative reacting toward DNA in solution under UV light exposition. This is performed through a combination of ground- and excited-state quantum chemistry, classical molecular dynamics, and hybrid QM/MM simulations to rationalize in detail the formation of DNA interstrand cross-links (ICLs) exerted by the noncanonical noncovalent photosensitizer. Unprecedented spatial and temporal resolution of these phenomena is achieved, revealing that the ICL is sequence-specific and that the fastest reactions take place at AT, GC, and GT steps involving either the opposite nucleobases or adjacent Watson-Crick base pairs. The N7 and O6 positions of guanine, the N7 and N3 sites of adenine, the N4 position of cytosine, and the O2 atom of thymine are deemed as the most nucleophile sites and are positively identified to participate in the ICL productions. This work provides a multiscale computational protocol to study DNA reactivity with noncovalent photosensitizers, and contributes to the understanding of therapies based on photoinduced DNA damage at molecular and electronic levels. In addition, we believe the depth understanding of these processes should assist the design of new photosensitizers considering their molecular size, electronic properties, and the observed regioselectivity toward nucleic acids.
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Affiliation(s)
| | - Antonio Monari
- Université Paris Cité, CNRS, ITODYS, F-75006 Paris, France.,Université de Lorraine and CNRS, UMR 7019 LPCT, F-5400 Nancy, France
| | - Iñaki Tuñón
- Departament de Química Física, Universitat de València, 46100 Burjassot, Spain
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12
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Transformation characteristics of A-DNA in salt solution revealed through molecular dynamics simulations. Biophys Chem 2022; 288:106845. [DOI: 10.1016/j.bpc.2022.106845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/25/2022] [Accepted: 06/06/2022] [Indexed: 11/17/2022]
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13
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Pant P, Aggarwal L. Assessing the DNA structural integrity via selective annihilation of Watson-Crick hydrogen bonds: Insights from molecular dynamics simulations. Biophys Chem 2022; 282:106758. [DOI: 10.1016/j.bpc.2021.106758] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/09/2021] [Accepted: 12/30/2021] [Indexed: 01/17/2023]
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14
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Vasiliu T, Mocci F, Laaksonen A, Engelbrecht LDV, Perepelytsya S. Caging Polycations: Effect of Increasing Confinement on the Modes of Interaction of Spermidine3+ With DNA Double Helices. Front Chem 2022; 10:836994. [PMID: 35281557 PMCID: PMC8915389 DOI: 10.3389/fchem.2022.836994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/04/2022] [Indexed: 11/23/2022] Open
Abstract
Polyamines have important roles in the modulation of the cellular function and are ubiquitous in cells. The polyamines putrescine2+, spermidine3+, and spermine4+ represent the most abundant organic counterions of the negatively charged DNA in the cellular nucleus. These polyamines are known to stabilize the DNA structure and, depending on their concentration and additional salt composition, to induce DNA aggregation, which is often referred to as condensation. However, the modes of interactions of these elongated polycations with DNA and how they promote condensation are still not clear. In the present work, atomistic molecular dynamics (MD) computer simulations of two DNA fragments surrounded by spermidine3+ (Spd3+) cations were performed to study the structuring of Spd3+ “caged” between DNA molecules. Microsecond time scale simulations, in which the parallel DNA fragments were constrained at three different separations, but allowed to rotate axially and move naturally, provided information on the conformations and relative orientations of surrounding Spm3+ cations as a function of DNA-DNA separation. Novel geometric criteria allowed for the classification of DNA-Spd3+ interaction modes, with special attention given to Spd3+ conformational changes in the space between the two DNA molecules (caged Spd3+). This work shows how changes in the accessible space, or confinement, around DNA affect DNA-Spd3+ interactions, information fundamental to understanding the interactions between DNA and its counterions in environments where DNA is compacted, e.g. in the cellular nucleus.
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Affiliation(s)
- Tudor Vasiliu
- Centre of Advanced Research in Bionanoconjugates and Biopolymers “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania
| | - Francesca Mocci
- Dipartimento di Scienze Chimiche e Geologiche, Cagliari University, Cagliari, Italy
- *Correspondence: Francesca Mocci, ; Aatto Laaksonen, ; Sergiy Perepelytsya,
| | - Aatto Laaksonen
- Centre of Advanced Research in Bionanoconjugates and Biopolymers “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania
- Dipartimento di Scienze Chimiche e Geologiche, Cagliari University, Cagliari, Italy
- Division of Energy Science, Energy Engineering, Luleå University of Technology, Luleå, Sweden
- Division of Physical Chemistry, Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden
- State Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing, China
- *Correspondence: Francesca Mocci, ; Aatto Laaksonen, ; Sergiy Perepelytsya,
| | | | - Sergiy Perepelytsya
- Bogolyubov Institute for Theoretical Physics of the NAS of Ukraine, Kyiv, Ukraine
- *Correspondence: Francesca Mocci, ; Aatto Laaksonen, ; Sergiy Perepelytsya,
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15
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Yu B, Bien KG, Pletka CC, Iwahara J. Dynamics of Cations around DNA and Protein as Revealed by 23Na Diffusion NMR Spectroscopy. Anal Chem 2022; 94:2444-2452. [PMID: 35080384 PMCID: PMC8829827 DOI: 10.1021/acs.analchem.1c04197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Counterions are vital for the structure and function of biomolecules. However, the behavior of counterions remains elusive due to the difficulty in characterizing mobile ions. Here, we demonstrate that the dynamics of cations around biological macromolecules can be revealed by 23Na diffusion nuclear magnetic resonance (NMR) spectroscopy. NMR probe hardware capable of generating strong magnetic field gradients enables 23Na NMR-based diffusion measurements for Na+ ions in solutions of biological macromolecules and their complexes. The dynamic properties of Na+ ions interacting with the macromolecules can be investigated using apparent 23Na diffusion coefficients measured under various conditions. Our diffusion data clearly show that Na+ ions retain high mobility within the ion atmosphere around DNA. The 23Na diffusion NMR method also permits direct observation of the release of Na+ ions from nucleic acids upon protein-nucleic acid association. The entropy change due to the ion release can be estimated from the diffusion data.
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Affiliation(s)
- Binhan Yu
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas 77555-1068 United States
| | - Karina G Bien
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas 77555-1068 United States
| | - Channing C Pletka
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas 77555-1068 United States
| | - Junji Iwahara
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas 77555-1068 United States
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16
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Martin B, Dans PD, Wieczór M, Villegas N, Brun-Heath I, Battistini F, Terrazas M, Orozco M. Molecular basis of Arginine and Lysine DNA sequence-dependent thermo-stability modulation. PLoS Comput Biol 2022; 18:e1009749. [PMID: 35007284 PMCID: PMC8782489 DOI: 10.1371/journal.pcbi.1009749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 01/21/2022] [Accepted: 12/13/2021] [Indexed: 11/19/2022] Open
Abstract
We have used a variety of theoretical and experimental techniques to study the role of four basic amino acids-Arginine, Lysine, Ornithine and L-2,4-Diaminobutyric acid-on the structure, flexibility and sequence-dependent stability of DNA. We found that the presence of organic ions stabilizes the duplexes and significantly reduces the difference in stability between AT- and GC-rich duplexes with respect to the control conditions. This suggests that these amino acids, ingredients of the primordial soup during abiogenesis, could have helped to equalize the stability of AT- and GC-rich DNA oligomers, facilitating a general non-catalysed self-replication of DNA. Experiments and simulations demonstrate that organic ions have an effect that goes beyond the general electrostatic screening, involving specific interactions along the grooves of the double helix. We conclude that organic ions, largely ignored in the DNA world, should be reconsidered as crucial structural elements far from mimics of small inorganic cations.
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Affiliation(s)
- Benjamin Martin
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
- Institute of Bioengineering, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Pablo D. Dans
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
- Department of Biological Sciences, CENUR Litoral Norte, Universidad de la República (UdelaR), Salto, Uruguay
- Functional Genomics Unit, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Milosz Wieczór
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Nuria Villegas
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Isabelle Brun-Heath
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Federica Battistini
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Montserrat Terrazas
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology, Barcelona, Spain
- Department of Biochemistry and Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain
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17
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Fingerhut BP. The mutual interactions of RNA, counterions and water - quantifying the electrostatics at the phosphate-water interface. Chem Commun (Camb) 2021; 57:12880-12897. [PMID: 34816825 PMCID: PMC8640580 DOI: 10.1039/d1cc05367a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/01/2021] [Indexed: 11/25/2022]
Abstract
The structure and dynamics of polyanionic biomolecules, like RNA, are decisively determined by their electric interactions with the water molecules and the counterions in the environment. The solvation dynamics of the biomolecules involves a subtle balance of non-covalent and many-body interactions with structural fluctuations due to thermal motion occurring in a femto- to subnanosecond time range. This complex fluctuating many particle scenario is crucial in defining the properties of biological interfaces with far reaching significance for the folding of RNA structures and for facilitating RNA-protein interactions. Given the inherent complexity, suited model systems, carefully calibrated and benchmarked by experiments, are required to quantify the relevant interactions of RNA with the aqueous environment. In this feature article we summarize our recent progress in the understanding of the electrostatics at the biological interface of double stranded RNA (dsRNA) and transfer RNA (tRNA). Dimethyl phosphate (DMP) is introduced as a viable and rigorously accessible model system allowing the interaction strength with water molecules and counterions, their relevant fluctuation timescales and the spatial reach of interactions to be established. We find strong (up to ≈90 MV cm-1) interfacial electric fields with fluctuations extending up to ≈20 THz and demonstrate how the asymmetric stretching vibration νAS(PO2)- of the polarizable phosphate group can serve as the most sensitive probe for interfacial interactions, establishing a rigorous link between simulations and experiment. The approach allows for the direct interfacial observation of interactions of biologically relevant Mg2+ counterions with phosphate groups in contact pair geometries via the rise of a new absorption band imposed by exchange repulsion interactions at short interatomic distances. The systematic extension to RNA provides microscopic insights into the changes of the hydration structure that accompany the temperature induced melting of the dsRNA double helix and quantify the ionic interactions in the folded tRNA. The results show that pairs of negatively charged phosphate groups and Mg2+ ions represent a key structural feature of RNA embedded in water. They highlight the importance of binding motifs made of contact pairs in the electrostatic stabilization of RNA structures that have a strong impact on the surface potential and enable the fine tuning of the local electrostatic properties which are expected to be relevant for mediating the interactions between biomolecules.
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18
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Comparison of the ionic effects of Ca2+ and Mg2+ on nucleic acids in liquids. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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19
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Sequence-dependent structural properties of B-DNA: what have we learned in 40 years? Biophys Rev 2021; 13:995-1005. [DOI: 10.1007/s12551-021-00893-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 11/01/2021] [Indexed: 11/27/2022] Open
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20
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Allahkaram L, Monari A, Dumont E. The Behavior of Triplet Thymine in a Model B-DNA Strand. Energetics and Spin Density Localization Revealed by ab initio Molecular Dynamics Simulations †. Photochem Photobiol 2021; 98:633-639. [PMID: 34699615 DOI: 10.1111/php.13549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 10/20/2021] [Indexed: 11/28/2022]
Abstract
Among the naturally occurring nucleobases, thymine presents the lowest triplet state, hence it represents a hotspot for energy transfer and photosensitization. In turn, the population of the triplet state may lead to thymine dimerization and hence to the production of toxic DNA lesions and has been the subject of intensive theoretical and experimental investigations. Relying on QM/MM molecular dynamics simulations, we have sought to situate the energy of the lowest triplet state of thymine embedded in a B-DNA environment. The energy gap varies between 305 and 329 kJ mol-1 when a single thymine is treated at the quantum chemistry level, depending on its position in the model double-stranded 16-bp oligonucleotide. The energy of triplet state decreases up to 300 kJ mol-1 , due to polarization effects, when we consider coupled stacked nucleobases up to the inclusion of four nucleobases. Our value lies in good agreement with the energy inferred experimentally by Miranda and coworkers (270 kJ mol-1 ), and our theoretical exploration opens the door to investigations toward other more complex and biologically relevant environments, such as thymines embedded in nucleosome core particles. Our investigations also provide a reference for further studies using semi-empirical approaches such as density functional-based tight-binding, allowing to further rationalize sequence effects.
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Affiliation(s)
- Laleh Allahkaram
- Laboratoire de Chimie, CNRS UMR 5182, ENS de Lyon, Univ Lyon, Lyon, France
| | - Antonio Monari
- Université de Lorraine and CNRS, LPCT UMR 7019, Nancy, France.,Université de Paris and CNRS, Itodys, Paris, France
| | - Elise Dumont
- Laboratoire de Chimie, CNRS UMR 5182, ENS de Lyon, Univ Lyon, Lyon, France.,Institut Universitaire de France, Paris, France
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21
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Stellwagen NC. Using capillary electrophoresis to characterize the hydrodynamic and electrostatic properties of DNA in solutions containing various monovalent cations. Electrophoresis 2021; 43:309-326. [PMID: 34510492 DOI: 10.1002/elps.202100176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 08/27/2021] [Accepted: 09/03/2021] [Indexed: 11/08/2022]
Abstract
This review describes the results obtained by using free-solution capillary electrophoresis to probe the electrostatic and hydrodynamic properties of DNA in solutions containing various monovalent cations. In brief, we found that the mobilities of double-stranded DNAs (dsDNAs) increase with increasing molecular weight before leveling off and becoming constant at molecular weights ≥400 bp. The mobilities of single-stranded DNAs (ssDNAs) go through a maximum at ∼10-20 nucleotides before decreasing and becoming constant for oligomers larger than ∼30-50 bases. The mobilities of both ss- and dsDNAs increase linearly with the logarithm of increasing charge per unit length and decrease linearly with the logarithm of increasing ionic strength. Surprisingly, ss- and dsDNA mobilities level off and become nearly constant at ionic strengths ≥0.6 M. The thermal stabilities of dsDNAs decrease linearly with increasing solution viscosity. The diffusion coefficients of dsDNA are modulated by the diffusion coefficients of their counterions because of electrostatic DNA-cation coupling interactions. Finally, the anomalously slow mobilities observed for A-tract-containing DNAs can be attributed both to differences in shape and to the preferential localization of small cations in the A-tract minor groove. Since many of these results are mirrored in other polyion-counterion systems, free-solution electrophoresis can be viewed as a reporter of the electrostatics and hydrodynamics of highly charged polyions. New results describing the mobilities of dsDNA analogues of a microRNA-messenger RNA complex are also presented.
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22
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Hörberg J, Moreau K, Tamás MJ, Reymer A. Sequence-specific dynamics of DNA response elements and their flanking sites regulate the recognition by AP-1 transcription factors. Nucleic Acids Res 2021; 49:9280-9293. [PMID: 34387667 PMCID: PMC8450079 DOI: 10.1093/nar/gkab691] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/21/2021] [Accepted: 07/27/2021] [Indexed: 11/28/2022] Open
Abstract
Activator proteins 1 (AP-1) comprise one of the largest families of eukaryotic basic leucine zipper transcription factors. Despite advances in the characterization of AP-1 DNA-binding sites, our ability to predict new binding sites and explain how the proteins achieve different gene expression levels remains limited. Here we address the role of sequence-specific DNA flexibility for stability and specific binding of AP-1 factors, using microsecond-long molecular dynamics simulations. As a model system, we employ yeast AP-1 factor Yap1 binding to three different response elements from two genetic environments. Our data show that Yap1 actively exploits the sequence-specific flexibility of DNA within the response element to form stable protein–DNA complexes. The stability also depends on the four to six flanking nucleotides, adjacent to the response elements. The flanking sequences modulate the conformational adaptability of the response element, making it more shape-efficient to form specific contacts with the protein. Bioinformatics analysis of differential expression of the studied genes supports our conclusions: the stability of Yap1–DNA complexes, modulated by the flanking environment, influences the gene expression levels. Our results provide new insights into mechanisms of protein–DNA recognition and the biological regulation of gene expression levels in eukaryotes.
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Affiliation(s)
- Johanna Hörberg
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden
| | - Kevin Moreau
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden
| | - Markus J Tamás
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden
| | - Anna Reymer
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden
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23
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Xu HT, Zhang N, Li MR, Zhang FS. Anion effect of Cl−, I−, and F− on counterions condensation within nucleic acid ion atmosphere. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115899] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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24
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He W, Chen YL, Pollack L, Kirmizialtin S. The structural plasticity of nucleic acid duplexes revealed by WAXS and MD. SCIENCE ADVANCES 2021; 7:7/17/eabf6106. [PMID: 33893104 PMCID: PMC8064643 DOI: 10.1126/sciadv.abf6106] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 03/05/2021] [Indexed: 05/06/2023]
Abstract
Double-stranded DNA (dsDNA) and RNA (dsRNA) helices display an unusual structural diversity. Some structural variations are linked to sequence and may serve as signaling units for protein-binding partners. Therefore, elucidating the mechanisms and factors that modulate these variations is of fundamental importance. While the structural diversity of dsDNA has been extensively studied, similar studies have not been performed for dsRNA. Because of the increasing awareness of RNA's diverse biological roles, such studies are timely and increasingly important. We integrate solution x-ray scattering at wide angles (WAXS) with all-atom molecular dynamics simulations to explore the conformational ensemble of duplex topologies for different sequences and salt conditions. These tightly coordinated studies identify robust correlations between features in the WAXS profiles and duplex geometry and enable atomic-level insights into the structural diversity of DNA and RNA duplexes. Notably, dsRNA displays a marked sensitivity to the valence and identity of its associated cations.
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Affiliation(s)
- Weiwei He
- Chemistry Program, Science Division, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
- Department of Chemistry, New York University, New York, NY, USA
| | - Yen-Lin Chen
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Lois Pollack
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
| | - Serdal Kirmizialtin
- Chemistry Program, Science Division, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates.
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25
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Mondal M, Yang L, Cai Z, Patra P, Gao YQ. A perspective on the molecular simulation of DNA from structural and functional aspects. Chem Sci 2021; 12:5390-5409. [PMID: 34168783 PMCID: PMC8179617 DOI: 10.1039/d0sc05329e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
As genetic material, DNA not only carries genetic information by sequence, but also affects biological functions ranging from base modification to replication, transcription and gene regulation through its structural and dynamic properties and variations. The motion and structural properties of DNA involved in related biological processes are also multi-scale, ranging from single base flipping to local DNA deformation, TF binding, G-quadruplex and i-motif formation, TAD establishment, compartmentalization and even chromosome territory formation, just to name a few. The sequence-dependent physical properties of DNA play vital role in all these events, and thus it is interesting to examine how simple sequence information affects DNA and the formation of the chromatin structure in these different hierarchical orders. Accordingly, molecular simulations can provide atomistic details of interactions and conformational dynamics involved in different biological processes of DNA, including those inaccessible by current experimental methods. In this perspective, which is mainly based on our recent studies, we provide a brief overview of the atomistic simulations on how the hierarchical structure and dynamics of DNA can be influenced by its sequences, base modifications, environmental factors and protein binding in the context of the protein-DNA interactions, gene regulation and structural organization of chromatin. We try to connect the DNA sequence, the hierarchical structures of DNA and gene regulation.
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Affiliation(s)
- Manas Mondal
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory 518055 Shenzhen China
| | - Lijiang Yang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China
| | - Zhicheng Cai
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China.,Biomedical Pioneering Innovation Center, Peking University 100871 Beijing China
| | - Piya Patra
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory 518055 Shenzhen China .,Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China
| | - Yi Qin Gao
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory 518055 Shenzhen China .,Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China.,Biomedical Pioneering Innovation Center, Peking University 100871 Beijing China.,Beijing Advanced Innovation Center for Genomics, Peking University 100871 Beijing China
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26
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Zdorevskyi OO, Perepelytsya SM. Dynamics of K + counterions around DNA double helix in the external electric field: A molecular dynamics study. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2020; 43:77. [PMID: 33306165 DOI: 10.1140/epje/i2020-12000-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 11/05/2020] [Indexed: 06/12/2023]
Abstract
The structure of DNA double helix is stabilized by metal counterions condensed to a diffuse layer around the macromolecule. The dynamics of counterions in real conditions is governed by the electric fields from DNA and other biological macromolecules. In the present work the molecular dynamics study was performed for the system of DNA double helix with neutralizing K+ counterions and for the system of KCl salt solution in an external electric field of different strength (up to 32mV/Å). The analysis of ionic conductivities of these systems has shown that the counterions around the DNA double helix are slowed down compared with the KCl salt solution. The calculated values of ion mobility are within (0.05-0.4)mS/cm depending on the orientation of the external electric field relatively to the double helix. Under the electric field parallel to the macromolecule K+ counterions move along the grooves of the double helix staying longer in the places with narrower minor groove. Under the electric field perpendicular to the macromolecule the dynamics of counterions is less affected by DNA atoms, and starting with the electric field values about 30mV/Å the double helix undergoes a phase transition from a double-stranded to a single-strand state.
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Affiliation(s)
- O O Zdorevskyi
- Bogolyubov Institute for Theoretical Physics of the National Academy of Sciences of Ukraine, 14-b, Metrolohichna Str., 03143, Kiev, Ukraine.
| | - S M Perepelytsya
- Bogolyubov Institute for Theoretical Physics of the National Academy of Sciences of Ukraine, 14-b, Metrolohichna Str., 03143, Kiev, Ukraine
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27
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Fossépré M, Tuvi-Arad I, Beljonne D, Richeter S, Clément S, Surin M. Binding Mode Multiplicity and Multiscale Chirality in the Supramolecular Assembly of DNA and a π-Conjugated Polymer. Chemphyschem 2020; 21:2543-2552. [PMID: 32910539 DOI: 10.1002/cphc.202000630] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/04/2020] [Indexed: 02/04/2023]
Abstract
Water-soluble π-conjugated polymers are increasingly considered for DNA biosensing. However, the conformational rearrangement, supramolecular organization and dynamics upon interaction with DNA have been overlooked, which prevents the rational design of such detection tools. To elucidate the binding of a cationic polythiophene (CPT) to DNA with atomistic resolution, we performed molecular simulations of their supramolecular assembly. Comparison of replicated simulations show a multiplicity of CPT binding geometries that contribute to the wrapping of CPT around DNA. The different binding geometries are stabilized by both electrostatic interactions between CPT lateral cations and DNA phosphodiesters and van der Waals interactions between the CPT backbone and the DNA grooves. Simulated circular dichroism (CD) spectra show that the induced CD signal stems from a conserved geometrical feature across the replicated simulations, i. e. the presence of segments of syn configurations between thiophene units along the CPT chain. At the macromolecular scale, we inspected the different shapes related to the CPT binding modes around the DNA through symmetry metrics. Altogether, molecular dynamics (MD) simulations, model Hamiltonian calculations of the CD spectra, and symmetry indices provide insights into the origin of induced chirality from the atomic to the macromolecular scale. Our multidisciplinary approach points out the hierarchical aspect of CPT chiral organization induced by DNA.
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Affiliation(s)
- Mathieu Fossépré
- Laboratory for Chemistry of Novel Materials, Centre of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons - UMONS, 20 Place du Parc, Mons, 7000, Belgium
| | - Inbal Tuvi-Arad
- Department of Natural Sciences, The Open University of Israel, Raanana, Israel
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, Centre of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons - UMONS, 20 Place du Parc, Mons, 7000, Belgium
| | | | | | - Mathieu Surin
- Laboratory for Chemistry of Novel Materials, Centre of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons - UMONS, 20 Place du Parc, Mons, 7000, Belgium
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28
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Hörberg J, Reymer A. Specifically bound BZIP transcription factors modulate DNA supercoiling transitions. Sci Rep 2020; 10:18795. [PMID: 33139763 PMCID: PMC7606469 DOI: 10.1038/s41598-020-75711-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 10/18/2020] [Indexed: 01/01/2023] Open
Abstract
Torsional stress on DNA, introduced by molecular motors, constitutes an important regulatory mechanism of transcriptional control. Torsional stress can modulate specific binding of transcription factors to DNA and introduce local conformational changes that facilitate the opening of promoters and nucleosome remodelling. Using all-atom microsecond scale molecular dynamics simulations together with a torsional restraint that controls the total twist of a DNA fragment, we address the impact of torsional stress on DNA complexation with a human BZIP transcription factor, MafB. We gradually over- and underwind DNA alone and in complex with MafB by 0.5° per dinucleotide step, starting from the relaxed state to a maximum of 5° per dinucleotide step, monitoring the evolution of the protein-DNA contacts at different degrees of torsional strain. Our computations show that MafB changes the DNA sequence-specific response to torsional stress. The dinucleotide steps that are susceptible to absorbing most of the torsional stress become more torsionally rigid, as they are involved in protein-DNA contacts. Also, the protein undergoes substantial conformational changes to follow the stress-induced DNA deformation, but mostly maintains the specific contacts with DNA. This results in a significant asymmetric increase of free energy of DNA twisting transitions, relative to free DNA, where overtwisting is more energetically unfavourable. Our data suggest that specifically bound BZIP factors could act as torsional stress insulators, modulating the propagation of torsional stress along the chromatin fibre, which might promote cooperative binding of collaborative DNA-binding factors.
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Affiliation(s)
- Johanna Hörberg
- Department of Chemistry and Molecular Biology, University of Gothenburg, 40530, Gothenburg, Sweden
| | - Anna Reymer
- Department of Chemistry and Molecular Biology, University of Gothenburg, 40530, Gothenburg, Sweden.
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29
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Abstract
![]()
Molecular association of proteins with nucleic
acids is required
for many biological processes essential to life. Electrostatic interactions
via ion pairs (salt bridges) of nucleic acid phosphates and protein
side chains are crucial for proteins to bind to DNA or RNA. Counterions
around the macromolecules are also key constituents for the thermodynamics
of protein–nucleic acid association. Until recently, there
had been only a limited amount of experiment-based information about
how ions and ionic moieties behave in biological macromolecular processes.
In the past decade, there has been significant progress in quantitative
experimental research on ionic interactions with nucleic acids and
their complexes with proteins. The highly negatively charged surfaces
of DNA and RNA electrostatically attract and condense cations, creating
a zone called the ion atmosphere. Recent experimental studies were
able to examine and validate theoretical models on ions and their
mobility and interactions with macromolecules. The ionic interactions
are highly dynamic. The counterions rapidly diffuse within the ion
atmosphere. Some of the ions are released from the ion atmosphere
when proteins bind to nucleic acids, balancing the charge via intermolecular
ion pairs of positively charged side chains and negatively charged
backbone phosphates. Previously, the release of counterions had been
implicated indirectly by the salt-concentration dependence of the
association constant. Recently, direct detection of counterion
release by NMR spectroscopy
has become possible and enabled more accurate and quantitative analysis
of the counterion release and its entropic impact on the thermodynamics
of protein–nucleic acid association. Recent studies also revealed
the dynamic nature of ion pairs of protein side chains and nucleic
acid phosphates. These ion pairs undergo transitions between two major
states. In one of the major states, the cation and the anion are in
direct contact and form hydrogen bonds. In the other major state,
the cation and the anion are separated by water. Transitions between
these states rapidly occur on a picosecond to nanosecond time scale.
When proteins interact with nucleic acids, interfacial arginine (Arg)
and lysine (Lys) side chains exhibit considerably different behaviors.
Arg side chains show a higher propensity to form rigid contacts with
nucleotide bases, whereas Lys side chains tend to be more mobile at
the molecular interfaces. The dynamic ionic interactions may facilitate
adaptive molecular recognition and play both thermodynamic and kinetic
roles in protein–nucleic acid interactions.
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Affiliation(s)
- Binhan Yu
- Department of Biochemistry & Molecular Biology, Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas 77555-1068, United States
| | - B. Montgomery Pettitt
- Department of Biochemistry & Molecular Biology, Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas 77555-1068, United States
| | - Junji Iwahara
- Department of Biochemistry & Molecular Biology, Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas 77555-1068, United States
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30
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Møller Sønderskov S, Hyldgaard Klausen L, Amland Skaanvik S, Han X, Dong M. In situ Surface Charge Density Visualization of Self-assembled DNA Nanostructures after Ion Exchange. Chemphyschem 2020; 21:1474-1482. [PMID: 32330354 PMCID: PMC7891384 DOI: 10.1002/cphc.201901168] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 04/14/2020] [Indexed: 12/30/2022]
Abstract
The charge density of DNA is a key parameter in strand hybridization and for the interactions occurring between DNA and molecules in biological systems. Due to the intricate structure of DNA, visualization of the surface charge density of DNA nanostructures under physiological conditions was not previously possible. Here, we perform a simultaneous analysis of the topography and surface charge density of DNA nanostructures using atomic force microscopy and scanning ion conductance microscopy. The effect of in situ ion exchange using various alkali metal ions is tested with respect to the adsorption of DNA origami onto mica, and a quantitative study of surface charge density reveals ion exchange phenomena in mica as a key parameter in DNA adsorption. This is important for structure-function studies of DNA nanostructures. The research provides an efficient approach to study surface charge density of DNA origami nanostructures and other biological molecules at a single molecule level.
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Affiliation(s)
| | - Lasse Hyldgaard Klausen
- Interdisciplinary Nanoscience Center (iNANO)Aarhus University, Denmark
- Department of ChemistryStanford University333 Campus DriveStanfordCA 94305USA
| | | | - Xiaojun Han
- State Key Laboratory of Urban Water Resource and EnvironmentSchool of Chemistry and Chemical EngineeringHarbin Institute of Technology, China
| | - Mingdong Dong
- Interdisciplinary Nanoscience Center (iNANO)Aarhus University, Denmark
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32
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Vermeulen JG, Burt F, van Heerden E, du Preez LL, Meiring M. Characterization of the inhibition mechanism of a tissuefactor inhibiting single-chain variable fragment: a combined computational approach. J Mol Model 2020; 26:87. [PMID: 32219568 DOI: 10.1007/s00894-020-4350-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 03/11/2020] [Indexed: 10/24/2022]
Abstract
The interaction of a single-chain variable fragment (scFv) directed against human tissue factor (TF) was predicted using an in silico approach with the aim to establish a most likely mechanism of inhibition. The structure of the TF inhibiting scFv (TFI-scFv) was predicted using homology modeling, and complementarity-determining regions (CDRs) were identified. The CDR was utilized to direct molecular docking between the homology model of TFI-scFv and the crystal structure of the extracellular domains of human tissue factor. The rigid-body docking model was refined by means of molecular dynamic (MD) simulations, and the most prevalent cluster was identified. MD simulations predicted improved interaction between TFI-scFv and TF and propose the formation of stable complex for duration of the 600-ns simulation. Analysis of the refined docking model suggests that the interactions between TFI-scFv would interfere with the allosterical activation of coagulation factor VII (FVII) by TF. This interaction would prevent the formation of the active TF:VIIa complex and in so doing inhibit the initiation phase of blood coagulation as observers during in vitro testing.
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Affiliation(s)
- Jan-G Vermeulen
- Department of Microbial, Biochemical and Food Biotechnology, Faculty of Agricultural Sciences, University of the Free State, Bloemfontein, South Africa. .,Department of Haematology and Cell Biology, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa.
| | - Felicity Burt
- Division of Virology, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa.,National Health Laboratory Service, Universitas, Bloemfontein, South Africa
| | - Esta van Heerden
- Department of Microbial, Biochemical and Food Biotechnology, Faculty of Agricultural Sciences, University of the Free State, Bloemfontein, South Africa
| | - Louis Lategan du Preez
- Department of Microbial, Biochemical and Food Biotechnology, Faculty of Agricultural Sciences, University of the Free State, Bloemfontein, South Africa
| | - Muriel Meiring
- Department of Haematology and Cell Biology, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa.,National Health Laboratory Service, Universitas, Bloemfontein, South Africa
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33
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Walther J, Dans PD, Balaceanu A, Hospital A, Bayarri G, Orozco M. A multi-modal coarse grained model of DNA flexibility mappable to the atomistic level. Nucleic Acids Res 2020; 48:e29. [PMID: 31956910 PMCID: PMC7049737 DOI: 10.1093/nar/gkaa015] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 12/10/2019] [Accepted: 01/04/2020] [Indexed: 12/13/2022] Open
Abstract
We present a new coarse grained method for the simulation of duplex DNA. The algorithm uses a generalized multi-harmonic model that can represent any multi-normal distribution of helical parameters, thus avoiding caveats of current mesoscopic models for DNA simulation and representing a breakthrough in the field. The method has been parameterized from accurate parmbsc1 atomistic molecular dynamics simulations of all unique tetranucleotide sequences of DNA embedded in long duplexes and takes advantage of the correlation between helical states and backbone configurations to derive atomistic representations of DNA. The algorithm, which is implemented in a simple web interface and in a standalone package reproduces with high computational efficiency the structural landscape of long segments of DNA untreatable by atomistic molecular dynamics simulations.
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Affiliation(s)
- Jürgen Walther
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| | - Pablo D Dans
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
- Department of Biological Sciences, CENUR North Coast, University of the Republic, 50000 Salto, Uruguay
| | - Alexandra Balaceanu
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| | - Adam Hospital
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| | - Genís Bayarri
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
- Department of Biochemistry and Biomedicine, The University of Barcelona, 08028 Barcelona, Spain
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34
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Bendandi A, Dante S, Zia SR, Diaspro A, Rocchia W. Chromatin Compaction Multiscale Modeling: A Complex Synergy Between Theory, Simulation, and Experiment. Front Mol Biosci 2020; 7:15. [PMID: 32158765 PMCID: PMC7051991 DOI: 10.3389/fmolb.2020.00015] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 01/27/2020] [Indexed: 12/24/2022] Open
Abstract
Understanding the mechanisms that trigger chromatin compaction, its patterns, and the factors they depend on, is a fundamental and still open question in Biology. Chromatin compacts and reinforces DNA and is a stable but dynamic structure, to make DNA accessible to proteins. In recent years, computational advances have provided larger amounts of data and have made large-scale simulations more viable. Experimental techniques for the extraction and reconstitution of chromatin fibers have improved, reinvigorating theoretical and experimental interest in the topic and stimulating debate on points previously considered as certainties regarding chromatin. A great assortment of approaches has emerged, from all-atom single-nucleosome or oligonucleosome simulations to various degrees of coarse graining, to polymer models, to fractal-like structures and purely topological models. Different fiber-start patterns have been studied in theory and experiment, as well as different linker DNA lengths. DNA is a highly charged macromolecule, making ionic and electrostatic interactions extremely important for chromatin topology and dynamics. Indeed, the repercussions of varying ionic concentration have been extensively examined at the computational level, using all-atom, coarse-grained, and continuum techniques. The presence of high-curvature AT-rich segments in DNA can cause conformational variations, attesting to the fact that the role of DNA is both structural and electrostatic. There have been some tentative attempts to describe the force fields governing chromatin conformational changes and the energy landscapes of these transitions, but the intricacy of the system has hampered reaching a consensus. The study of chromatin conformations is an intrinsically multiscale topic, influenced by a wide range of biological and physical interactions, spanning from the atomic to the chromosome level. Therefore, powerful modeling techniques and carefully planned experiments are required for an overview of the most relevant phenomena and interactions. The topic provides fertile ground for interdisciplinary studies featuring a synergy between theoretical and experimental scientists from different fields and the cross-validation of respective results, with a multi-scale perspective. Here, we summarize some of the most representative approaches, and focus on the importance of electrostatics and solvation, often overlooked aspects of chromatin modeling.
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Affiliation(s)
- Artemi Bendandi
- Physics Department, University of Genoa, Genoa, Italy
- Nanophysics & NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Silvia Dante
- Nanophysics & NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Syeda Rehana Zia
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
| | - Alberto Diaspro
- Physics Department, University of Genoa, Genoa, Italy
- Nanophysics & NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Walter Rocchia
- Concept Lab, Istituto Italiano di Tecnologia, Genoa, Italy
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35
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Perepelytsya S, Uličný J, Laaksonen A, Mocci F. Pattern preferences of DNA nucleotide motifs by polyamines putrescine2+, spermidine3+ and spermine4. Nucleic Acids Res 2020; 47:6084-6097. [PMID: 31114917 PMCID: PMC6614828 DOI: 10.1093/nar/gkz434] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 04/10/2019] [Accepted: 05/08/2019] [Indexed: 12/25/2022] Open
Abstract
The interactions of natural polyamines (putrescine2+, spermidine3+ and spermine4+) with DNA double helix are studied to characterize their nucleotide sequence pattern preference. Atomistic Molecular Dynamics simulations have been carried out for three systems consisting of the same DNA fragment d(CGCGAATTCGCGAATTCGCG) with different polyamines. The results show that polyamine molecules are localized with well-recognized patterns along the double helix with different residence times. We observed a clear hierarchy in the residence times of the polyamines, with the longest residence time (ca 100ns) in the minor groove. The analysis of the sequence dependence shows that polyamine molecules prefer the A-tract regions of the minor groove - in its narrowest part. The preferable localization of putrescine2+, spermidine3+ and spermine4+ in the minor groove with A-tract motifs is correlated with modulation of the groove width by a specific nucleotide sequences. We did develop a theoretical model pointing to the electrostatic interactions as the main driving force in this phenomenon, making it even more prominent for polyamines with higher charges. The results of the study explain the specificity of polyamine interactions with A-tract region of the DNA double helix which is also observed in experiments.
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Affiliation(s)
- Sergiy Perepelytsya
- Bogolyubov Institute for Theoretical Physics of the National Academy of Sciences of Ukraine, 03143 Kyiv, Ukraine.,Department of Theoretical and Mathematical Physics, Kyiv Academic University, 03142 Kyiv, Ukraine
| | - Jozef Uličný
- Department of Biophysics, Institute of Physics, P. J. Šafárik University, 041 54 Košice, Slovakia
| | - Aatto Laaksonen
- State Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, 210009 Nanjing, China.,Division of Physical Chemistry, Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.,Centre of Advanced Research in Bionanoconjugates and Biopolymers, Petru Poni Institute of Macromolecular Chemistry, Iasi, 700487, Romania
| | - Francesca Mocci
- Centre of Advanced Research in Bionanoconjugates and Biopolymers, Petru Poni Institute of Macromolecular Chemistry, Iasi, 700487, Romania.,Department of Chemical and Geological Sciences, University of Cagliari, I-09042 Monserrato, Italy
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36
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Zhao J, Cramer SM, McGown LB. Mechanism of sequence-based separation of single-stranded DNA in capillary zone electrophoresis. Electrophoresis 2020; 41:705-713. [PMID: 32031267 DOI: 10.1002/elps.201900418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/28/2019] [Accepted: 01/30/2020] [Indexed: 11/09/2022]
Abstract
Separation of DNA by length using CGE is a mature field. Separation of DNA by sequence, in contrast, is a more difficult problem. Existing techniques generally rely upon changes in intrinsic or induced differences in conformation. Previous work in our group showed that sets of ssDNA of the same length differing in sequence by as little as a single base could be separated by CZE using simple buffers at high ionic strength. Here, we explore the basis of the separation using circular dichroism spectroscopy, fluorescence anisotropy, and small angle X-ray scattering. The results reveal sequence-dependent differences among the same length strands, but the trends in the differences are not correlated to the migration order of the strands in the CZE separation. They also indicate that the separation is based on intrinsic differences among the strands that do not change with increasing ionic strength; rather, increasing ionic strength has a greater effect on electroosmotic mobility in the normal direction than on electrophoretic mobility of the strands in the reverse direction. This increases the migration time of the strands in the normal direction, allowing more time for the same-length strands to be teased apart based on very small differences in the intrinsic properties of the strands of different sequence. Regression analysis was used to model the intrinsic differences among DNA strands in order to gain insight into the relationship between mobility and sequence that underlies the separation.
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Affiliation(s)
- Jia Zhao
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Steven M Cramer
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Linda B McGown
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY, USA
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37
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Long MP, Alland S, Martin ME, Isborn CM. Molecular dynamics simulations of alkaline earth metal ions binding to DNA reveal ion size and hydration effects. Phys Chem Chem Phys 2020; 22:5584-5596. [DOI: 10.1039/c9cp06844a] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Classical molecular dynamics simulations reveal size-dependent trends of alkaline earth metal ions binding to DNA are due to ion size and hydration behavior.
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Affiliation(s)
| | - Serra Alland
- Department of Chemistry and Biochemistry
- University of Central Arkansas
- Arkansas 72035
- USA
| | - Madison E. Martin
- Department of Chemistry and Biochemistry
- University of Central Arkansas
- Arkansas 72035
- USA
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38
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Balaceanu A, Buitrago D, Walther J, Hospital A, Dans PD, Orozco M. Modulation of the helical properties of DNA: next-to-nearest neighbour effects and beyond. Nucleic Acids Res 2019; 47:4418-4430. [PMID: 30957854 PMCID: PMC6511876 DOI: 10.1093/nar/gkz255] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 03/23/2019] [Accepted: 03/30/2019] [Indexed: 12/21/2022] Open
Abstract
We used extensive molecular dynamics simulations to study the structural and dynamic properties of the central d(TpA) step in the highly polymorphic d(CpTpApG) tetranucleotide. Contrary to the assumption of the dinucleotide-model and its nearest neighbours (tetranucleotide-model), the properties of the central d(TpA) step change quite significantly dependent on the next-to-nearest (hexanucleotide) sequence context and in a few cases are modulated by even remote neighbours (beyond next-to-nearest from the central TpA). Our results highlight the existence of previously undescribed dynamical mechanisms for the transmission of structural information into the DNA and demonstrate the existence of certain sequences with special physical properties that can impact on the global DNA structure and dynamics.
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Affiliation(s)
- Alexandra Balaceanu
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Diana Buitrago
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Jürgen Walther
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Adam Hospital
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Pablo D Dans
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain.,Department of Biochemistry and Biomedicine, University of Barcelona, 08028 Barcelona, Spain
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39
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40
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Jaiswal AK, Srivastava R, Pandey P, Bandyopadhyay P. Microscopic picture of water-ethylene glycol interaction near a model DNA by computer simulation: Concentration dependence, structure, and localized thermodynamics. PLoS One 2018; 13:e0206359. [PMID: 30427849 PMCID: PMC6235303 DOI: 10.1371/journal.pone.0206359] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 10/11/2018] [Indexed: 01/03/2023] Open
Abstract
It is known that crowded molecular environment affects the structure, thermodynamics, and dynamics of macromolecules. Most of the previous works on molecular crowding have majorly focused on the behavior of the macromolecule with less emphasis on the behavior of the crowder and water molecules. In the current study, we have precisely focused on the behavior of the crowder, (ethylene glycol (EG)), salt ions, and water in the presence of a DNA with the increase of the EG concentration. We have probed the behavior of water and crowder using molecular dynamics (MD) simulation and by calculating localized thermodynamic properties. Our results show an interesting competition between EG and water molecules to make hydrogen bonds (H-bond) with DNA. Although the total number of H-bonds involving DNA with both EG and water remains essentially same irrespective of the increase in EG concentration, there is a proportional change in the H-bonding pattern between water-water, EG-EG, and EG-water near DNA and in bulk. At low concentrations of EG, the displacement of water molecules near DNA is relatively easy. However, the displacement of water becomes more difficult as the concentration of EG increases. The density of Na+ (Cl-) near DNA increases (decreases) as the concentration of EG is increased. The density of Cl- near Na+ increases with the increase in EG concentration. It was also found that the average free energy per water in the first solvation shell increases with the increase in EG concentration. Putting all these together, a microscopic picture of EG, water, salt interaction in the presence of DNA, as a function of EG concentration, has emerged.
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Affiliation(s)
- Atul Kumar Jaiswal
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Rakesh Srivastava
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Preeti Pandey
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Pradipta Bandyopadhyay
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
- * E-mail:
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41
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Francés-Monerris A, Gattuso H, Roca-Sanjuán D, Tuñón I, Marazzi M, Dumont E, Monari A. Dynamics of the excited-state hydrogen transfer in a (dG)·(dC) homopolymer: intrinsic photostability of DNA. Chem Sci 2018; 9:7902-7911. [PMID: 30450180 PMCID: PMC6202918 DOI: 10.1039/c8sc03252a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 09/17/2018] [Indexed: 12/12/2022] Open
Abstract
The intrinsic photostability of nucleic acids is intimately related to evolution of life, while its understanding at the molecular and electronic levels remains a challenge for modern science. Among the different decay pathways proposed in the last two decades, the excited-state hydrogen transfer between guanine-cytosine base pairs has been identified as an efficient non-reactive channel to dissipate the excess of energy provided by light absorption. The present work studies the dynamics of such phenomena taking place in a (dG)·(dC) B-DNA homopolymer in water solution using state-of-the-art molecular modelling and simulation methods. A dynamic effect that boosts the photostability of the inter-strand hydrogen atom transfers, inherent to the Watson-Crick base pairing, is unveiled and ascribed to the energy released during the proton transfer step. Our results also reveal a novel mechanism of DNA decay named four proton transfer (FPT), in which two protons of two adjacent G-C base pairs are transferred to form a biradical zwitterionic intermediate. Decay of the latter intermediate to the ground state triggers the transfer of the protons back to the guanine molecules recovering the Watson-Crick structure of the tetramer. This FPT process is activated by the close interaction of a nearby Na+ counterion with the oxygen atoms of the guanine nucleobases and hence represents a photostable channel operative in natural nucleic acids.
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Affiliation(s)
| | - Hugo Gattuso
- Theoretical Physical Chemistry , Research Unit Molecular Systems (UR MOLSYS) , University of Liège , 4000 Liège , Belgium
| | - Daniel Roca-Sanjuán
- Instituto de Ciencia Molecular , Universitat de València , Apartado 22085 , ES-46071 Paterna , Spain
| | - Iñaki Tuñón
- Departamento de Química Física , Universitat de València , 46100 Burjassot , Spain
| | - Marco Marazzi
- Departamento de Química , Centro de Investigación en Síntesis Química (CISQ) , Universidad de La Rioja , 26006 Logroño , Spain
| | - Elise Dumont
- Univ. Lyon , ENS de Lyon , CNRS UMR 5182 , Université Claude Bernard Lyon 1 , Laboratoire de Chimie , F69342 , Lyon , France
| | - Antonio Monari
- Université de Lorraine , CNRS , LPCT , Nancy F-54000 , France . ;
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42
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Balaceanu A, Pérez A, Dans PD, Orozco M. Allosterism and signal transfer in DNA. Nucleic Acids Res 2018; 46:7554-7565. [PMID: 29905860 PMCID: PMC6125689 DOI: 10.1093/nar/gky549] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/11/2018] [Accepted: 06/06/2018] [Indexed: 12/14/2022] Open
Abstract
We analysed the basic mechanisms of signal transmission in DNA and the origins of the allostery exhibited by systems such as the ternary complex BAMHI-DNA-GRDBD. We found that perturbation information generated by a primary protein binding event travels as a wave to distant regions of DNA following a hopping mechanism. However, such a structural perturbation is transient and does not lead to permanent changes in the DNA geometry and interaction properties at the secondary binding site. The BAMHI-DNA-GRDBD allosteric mechanism does not occur through any traditional models: direct (protein-protein), indirect (reorganization of the secondary site) readout or solvent-release. On the contrary, it is generated by a subtle and less common entropy-mediated mechanism, which might have an important role to explain other DNA-mediated cooperative effects.
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Affiliation(s)
- Alexandra Balaceanu
- Joint IRB-BSC Program on Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Alberto Pérez
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Pablo D Dans
- Joint IRB-BSC Program on Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Modesto Orozco
- Joint IRB-BSC Program on Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
- Department of Biochemistry and Biomedicine, University of Barcelona, 08028 Barcelona, Spain
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43
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Hydration of counterions interacting with DNA double helix: a molecular dynamics study. J Mol Model 2018; 24:171. [DOI: 10.1007/s00894-018-3704-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 06/06/2018] [Indexed: 12/12/2022]
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44
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Bie L, Du L, Yuan Q, Gao J. How a single 5-methylation of cytosine regulates the recognition of C/EBPβ transcription factor: a molecular dynamic simulation study. J Mol Model 2018; 24:159. [PMID: 29892907 DOI: 10.1007/s00894-018-3678-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 05/15/2018] [Indexed: 12/23/2022]
Abstract
CpG methylation can regulate gene expression by altering the specific binding of protein and DNA. In order to understand how a single 5mC regulates protein-DNA interactions, we have compared the structures and dynamics of CEBP/βprotein-DNA complexes before and after methylation, and the results indicate that even a single 5mC can regulate protein-DNA recognition by steric-hindrance effect of methyl group and changing the hydrogen bond interactions. The interactions between the methyl group, mCpG motif, and the conserved residue arginine make the protein read out the variation of local environment, which further enhances the specific recognition and affects the base pair stacking. The stacking interactions can propagate along the backbone of DNA and lead to long-range allosteric effects, including obvious conformational variations for DNA base pairs.
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Affiliation(s)
- Lihua Bie
- Agricultural Bioinformatics Key Laboratory of Hubei Province, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Likai Du
- Agricultural Bioinformatics Key Laboratory of Hubei Province, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Qiaoxia Yuan
- College of Engineering, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
| | - Jun Gao
- Agricultural Bioinformatics Key Laboratory of Hubei Province, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
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45
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Zhang C, Lu C, Jing Z, Wu C, Piquemal JP, Ponder JW, Ren P. AMOEBA Polarizable Atomic Multipole Force Field for Nucleic Acids. J Chem Theory Comput 2018; 14:2084-2108. [PMID: 29438622 PMCID: PMC5893433 DOI: 10.1021/acs.jctc.7b01169] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The AMOEBA polarizable atomic multipole force field for nucleic acids is presented. Valence and electrostatic parameters were determined from high-level quantum mechanical data, including structures, conformational energy, and electrostatic potentials, of nucleotide model compounds. Previously derived parameters for the phosphate group and nucleobases were incorporated. A total of over 35 μs of condensed-phase molecular dynamics simulations of DNA and RNA molecules in aqueous solution and crystal lattice were performed to validate and refine the force field. The solution and/or crystal structures of DNA B-form duplexes, RNA duplexes, and hairpins were captured with an average root-mean-squared deviation from NMR structures below or around 2.0 Å. Structural details, such as base pairing and stacking, sugar puckering, backbone and χ-torsion angles, groove geometries, and crystal packing interfaces, agreed well with NMR and/or X-ray. The interconversion between A- and B-form DNAs was observed in ethanol-water mixtures at 328 K. Crystal lattices of B- and Z-form DNA and A-form RNA were examined with simulations. For the RNA tetraloop, single strand tetramers, and HIV TAR with 29 residues, the simulated conformational states, 3 J-coupling, nuclear Overhauser effect, and residual dipolar coupling data were compared with NMR results. Starting from a totally unstacked/unfolding state, the rCAAU tetranucleotide was folded into A-form-like structures during ∼1 μs molecular dynamics simulations.
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Affiliation(s)
- Changsheng Zhang
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Chao Lu
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, United States
| | - Zhifeng Jing
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Chuanjie Wu
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, United States
| | - Jean-Philip Piquemal
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
- Laboratoire de Chimie Théorique, Sorbonne Universités, UPMC, UMR7616 CNRS, Paris, France
| | - Jay W. Ponder
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, United States
| | - Pengyu Ren
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
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46
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Brach K, Hatakeyama A, Nogues C, Olesiak-Banska J, Buckle M, Matczyszyn K. Photochemical analysis of structural transitions in DNA liquid crystals reveals differences in spatial structure of DNA molecules organized in liquid crystalline form. Sci Rep 2018. [PMID: 29540820 PMCID: PMC5852169 DOI: 10.1038/s41598-018-22863-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The anisotropic shape of DNA molecules allows them to form lyotropic liquid crystals (LCs) at high concentrations. This liquid crystalline arrangement is also found in vivo (e.g., in bacteriophage capsids, bacteria or human sperm nuclei). However, the role of DNA liquid crystalline organization in living organisms still remains an open question. Here we show that in vitro, the DNA spatial structure is significantly changed in mesophases compared to non-organized DNA molecules. DNA LCs were prepared from pBluescript SK (pBSK) plasmid DNA and investigated by photochemical analysis of structural transitions (PhAST). We reveal significant differences in the probability of UV-induced pyrimidine dimer photoproduct formation at multiple loci on the DNA indicative of changes in major groove architecture.
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Affiliation(s)
- Katarzyna Brach
- Advanced Materials Engineering and Modelling Group, Wroclaw University of Science and Technology, Wroclaw, 50370, Poland
| | - Akiko Hatakeyama
- LBPA, IDA, ENS Cachan, CNRS, Université Paris-Saclay, Cachan, F-94235, France
| | - Claude Nogues
- LBPA, IDA, ENS Cachan, CNRS, Université Paris-Saclay, Cachan, F-94235, France
| | - Joanna Olesiak-Banska
- Advanced Materials Engineering and Modelling Group, Wroclaw University of Science and Technology, Wroclaw, 50370, Poland
| | - Malcolm Buckle
- LBPA, IDA, ENS Cachan, CNRS, Université Paris-Saclay, Cachan, F-94235, France.
| | - Katarzyna Matczyszyn
- Advanced Materials Engineering and Modelling Group, Wroclaw University of Science and Technology, Wroclaw, 50370, Poland.
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47
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Kolev SK, Petkov PS, Rangelov MA, Trifonov DV, Milenov TI, Vayssilov GN. Interaction of Na+, K+, Mg2+ and Ca2+ counter cations with RNA. Metallomics 2018; 10:659-678. [DOI: 10.1039/c8mt00043c] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Data on the location of alkaline and alkaline earth ions at RNA from crystallography, spectroscopy and computational modeling are reviewed.
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Affiliation(s)
- Stefan K. Kolev
- Acad. E. Djakov Institute of Electronics
- Bulgarian Academy of Sciences
- 1784 Sofia
- Bulgaria
| | - Petko St. Petkov
- Faculty of Chemistry and Pharmacy
- University of Sofia
- 1126 Sofia
- Bulgaria
| | - Miroslav A. Rangelov
- Laboratory of BioCatalysis
- Institute of Organic Chemistry
- Bulgarian Academy of Sciences
- 1113 Sofia
- Bulgaria
| | | | - Teodor I. Milenov
- Acad. E. Djakov Institute of Electronics
- Bulgarian Academy of Sciences
- 1784 Sofia
- Bulgaria
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48
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Etheve L, Martin J, Lavery R. Decomposing protein-DNA binding and recognition using simplified protein models. Nucleic Acids Res 2017; 45:10270-10283. [PMID: 28973439 PMCID: PMC5622342 DOI: 10.1093/nar/gkx627] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/11/2017] [Indexed: 12/30/2022] Open
Abstract
We analyze the role of different physicochemical factors in protein/DNA binding and recognition by comparing the results from all-atom molecular dynamics simulations with simulations using simplified protein models. These models enable us to separate the role of specific amino acid side chains, formal amino acid charges and hydrogen bonding from the effects of the low-dielectric volume occupied by the protein. Comparisons are made on the basis of the conformation of DNA after protein binding, the ionic distribution around the complex and the sequence specificity. The results for four transcription factors, binding in either the minor or major grooves of DNA, show that the protein volume and formal charges, with one exception, play a predominant role in binding. Adding hydrogen bonding and a very small number of key amino acid side chains at the all-atom level yields results in DNA conformations and sequence recognition close to those seen in the reference all-atom simulations.
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Affiliation(s)
- Loïc Etheve
- MMSB UMR 5086 CNRS / Univ. Lyon I, Institut de Biologie et Chimie des Protéines, 7 passage du Vercors, Lyon 69367, France
| | - Juliette Martin
- MMSB UMR 5086 CNRS / Univ. Lyon I, Institut de Biologie et Chimie des Protéines, 7 passage du Vercors, Lyon 69367, France
| | - Richard Lavery
- MMSB UMR 5086 CNRS / Univ. Lyon I, Institut de Biologie et Chimie des Protéines, 7 passage du Vercors, Lyon 69367, France
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49
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Pasi M, Zakrzewska K, Maddocks JH, Lavery R. Analyzing DNA curvature and its impact on the ionic environment: application to molecular dynamics simulations of minicircles. Nucleic Acids Res 2017; 45:4269-4277. [PMID: 28180333 PMCID: PMC5397150 DOI: 10.1093/nar/gkx092] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 02/07/2017] [Indexed: 01/16/2023] Open
Abstract
We propose a method for analyzing the magnitude and direction of curvature within nucleic acids, based on the curvilinear helical axis calculated by Curves+. The method is applied to analyzing curvature within minicircles constructed with varying degrees of over- or under-twisting. Using the molecular dynamics trajectories of three different minicircles, we are able to quantify how curvature varies locally both in space and in time. We also analyze how curvature influences the local environment of the minicircles, notably via increased heterogeneity in the ionic distributions surrounding the double helix. The approach we propose has been integrated into Curves+ and the utilities Canal (time trajectory analysis) and Canion (environmental analysis) and can be used to study a wide variety of static and dynamic structural data on nucleic acids.
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Affiliation(s)
- Marco Pasi
- MMSB, University of Lyon I/CNRS UMR 5086, Institut de Biologie et Chimie des Protéines, 7 Passage du Vercors, 69367 Lyon, France
| | - Krystyna Zakrzewska
- MMSB, University of Lyon I/CNRS UMR 5086, Institut de Biologie et Chimie des Protéines, 7 Passage du Vercors, 69367 Lyon, France
| | - John H Maddocks
- Section de Mathématiques, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Richard Lavery
- MMSB, University of Lyon I/CNRS UMR 5086, Institut de Biologie et Chimie des Protéines, 7 Passage du Vercors, 69367 Lyon, France
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50
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Abstract
The structure and function of biomolecules are strongly influenced by their hydration shells. Structural fluctuations and molecular excitations of hydrating water molecules cover a broad range in space and time, from individual water molecules to larger pools and from femtosecond to microsecond time scales. Recent progress in theory and molecular dynamics simulations as well as in ultrafast vibrational spectroscopy has led to new and detailed insight into fluctuations of water structure, elementary water motions, electric fields at hydrated biointerfaces, and processes of vibrational relaxation and energy dissipation. Here, we review recent advances in both theory and experiment, focusing on hydrated DNA, proteins, and phospholipids, and compare dynamics in the hydration shells to bulk water.
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Affiliation(s)
- Damien Laage
- École
Normale Supérieure, PSL Research University, UPMC Univ Paris
06, CNRS, Département de Chimie,
PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne
Universités, UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
| | - Thomas Elsaesser
- Max-Born-Institut
für Nichtlineare Optik und Kurzzeitspektroskopie, D-12489 Berlin, Germany
| | - James T. Hynes
- École
Normale Supérieure, PSL Research University, UPMC Univ Paris
06, CNRS, Département de Chimie,
PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne
Universités, UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
- Department
of Chemistry and Biochemistry, University
of Colorado, Boulder, Colorado 80309, United
States
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