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Verma S, Patidar RK, Tiwari K, Tiwari R, Baranwal J, Velayutham R, Ranjan N. Preferential Recognition of Human Telomeric G-Quadruplex DNA by a Red-Emissive Molecular Rotor. J Phys Chem B 2022; 126:7298-7309. [DOI: 10.1021/acs.jpcb.2c04418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Smita Verma
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, New Transit Campus, Lucknow 226002, Uttar Pradesh, India
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Kolkata, Maniktala Main Road, Kolkata 700054, India
| | - Rajesh K. Patidar
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, New Transit Campus, Lucknow 226002, Uttar Pradesh, India
| | - Khushboo Tiwari
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, New Transit Campus, Lucknow 226002, Uttar Pradesh, India
| | - Ratnesh Tiwari
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, New Transit Campus, Lucknow 226002, Uttar Pradesh, India
| | - Jaya Baranwal
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, New Transit Campus, Lucknow 226002, Uttar Pradesh, India
| | - Ravichandiran Velayutham
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Kolkata, Maniktala Main Road, Kolkata 700054, India
| | - Nihar Ranjan
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, New Transit Campus, Lucknow 226002, Uttar Pradesh, India
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2
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Li F, Luo Y, Xi G, Fu J, Tu J. Single-Molecule Analysis of DNA structures using nanopore sensors. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2022. [DOI: 10.1016/j.cjac.2022.100089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Ruthenium(II) Polypyridyl Complexes and Their Use as Probes and Photoreactive Agents for G-quadruplexes Labelling. Molecules 2022; 27:molecules27051541. [PMID: 35268640 PMCID: PMC8912042 DOI: 10.3390/molecules27051541] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 02/01/2023] Open
Abstract
Due to their optical and electrochemical properties, ruthenium(II) polypyridyl complexes have been used in a wide array of applications. Since the discovery of the light-switch ON effect of [Ru(bpy)2dppz]2+ when interacting with DNA, the design of new Ru(II) complexes as light-up probes for specific regions of DNA has been intensively explored. Amongst them, G-quadruplexes (G4s) are of particular interest. These structures formed by guanine-rich parts of DNA and RNA may be associated with a wide range of biological events. However, locating them and understanding their implications in biological pathways has proven challenging. Elegant approaches to tackle this challenge relies on the use of photoprobes capable of marking, reversibly or irreversibly, these G4s. Indeed, Ru(II) complexes containing ancillary π-deficient TAP ligands can create a covalently linked adduct with G4s after a photoinduced electron transfer from a guanine residue to the excited complex. Through careful design of the ligands, high selectivity of interaction with G4 structures can be achieved. This allows the creation of specific Ru(II) light-up probes and photoreactive agents for G4 labelling, which is at the core of this review composed of an introduction dedicated to a brief description of G-quadruplex structures and two main sections. The first one will provide a general picture of ligands and metal complexes interacting with G4s. The second one will focus on an exhaustive and comprehensive overview of the interactions and (photo)reactions of Ru(II) complexes with G4s.
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Price DA, Wedamulla P, Hill TD, Loth TM, Moran SD. The polarization dependence of 2D IR cross-peaks distinguishes parallel-stranded and antiparallel-stranded DNA G-quadruplexes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 267:120596. [PMID: 34801392 DOI: 10.1016/j.saa.2021.120596] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/01/2021] [Accepted: 11/04/2021] [Indexed: 06/13/2023]
Abstract
Guanine-rich nucleic acid sequences have a tendency to form four-stranded non-canonical motifs known as G-quadruplexes. These motifs may adopt a wide range of structures characterized by size, strand orientation, guanine base conformation, and fold topology. Using three K+-bound model systems, we show that vibrational coupling between guanine C6 = O and ring modes varies between parallel-stranded and antiparallel-stranded G-quadruplexes, and that such structures can be distinguished by comparison of the polarization dependences of cross-peaks in their two-dimensional infrared (2D IR) spectra. Combined with previously defined vibrational frequency trends, this analysis reveals key features of a 30-nucleotide unimolecular variant of the Bcl-2 proximal promoter that are consistent with its reported structure. This study shows that 2D IR spectroscopy is a convenient method for analyzing G-quadruplex structures that can be applied to complex sequences where traditional high-resolution methods are limited by solubility and disorder.
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Affiliation(s)
- David A Price
- School of Chemical and Biomolecular Sciences, Southern Illinois University Carbondale, 1245 Lincoln Drive MC 4409, Carbondale, IL 62901, United States
| | - Poornima Wedamulla
- School of Chemical and Biomolecular Sciences, Southern Illinois University Carbondale, 1245 Lincoln Drive MC 4409, Carbondale, IL 62901, United States
| | - Tayler D Hill
- School of Chemical and Biomolecular Sciences, Southern Illinois University Carbondale, 1245 Lincoln Drive MC 4409, Carbondale, IL 62901, United States
| | - Taylor M Loth
- School of Chemical and Biomolecular Sciences, Southern Illinois University Carbondale, 1245 Lincoln Drive MC 4409, Carbondale, IL 62901, United States
| | - Sean D Moran
- School of Chemical and Biomolecular Sciences, Southern Illinois University Carbondale, 1245 Lincoln Drive MC 4409, Carbondale, IL 62901, United States.
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Teng FY, Jiang ZZ, Guo M, Tan XZ, Chen F, Xi XG, Xu Y. G-quadruplex DNA: a novel target for drug design. Cell Mol Life Sci 2021; 78:6557-6583. [PMID: 34459951 PMCID: PMC11072987 DOI: 10.1007/s00018-021-03921-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/13/2021] [Accepted: 08/12/2021] [Indexed: 02/08/2023]
Abstract
G-quadruplex (G4) DNA is a type of quadruple helix structure formed by a continuous guanine-rich DNA sequence. Emerging evidence in recent years authenticated that G4 DNA structures exist both in cell-free and cellular systems, and function in different diseases, especially in various cancers, aging, neurological diseases, and have been considered novel promising targets for drug design. In this review, we summarize the detection method and the structure of G4, highlighting some non-canonical G4 DNA structures, such as G4 with a bulge, a vacancy, or a hairpin. Subsequently, the functions of G4 DNA in physiological processes are discussed, especially their regulation of DNA replication, transcription of disease-related genes (c-MYC, BCL-2, KRAS, c-KIT et al.), telomere maintenance, and epigenetic regulation. Typical G4 ligands that target promoters and telomeres for drug design are also reviewed, including ellipticine derivatives, quinoxaline analogs, telomestatin analogs, berberine derivatives, and CX-5461, which is currently in advanced phase I/II clinical trials for patients with hematologic cancer and BRCA1/2-deficient tumors. Furthermore, since the long-term stable existence of G4 DNA structures could result in genomic instability, we summarized the G4 unfolding mechanisms emerged recently by multiple G4-specific DNA helicases, such as Pif1, RecQ family helicases, FANCJ, and DHX36. This review aims to present a general overview of the field of G-quadruplex DNA that has progressed in recent years and provides potential strategies for drug design and disease treatment.
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Affiliation(s)
- Fang-Yuan Teng
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Zong-Zhe Jiang
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Man Guo
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Xiao-Zhen Tan
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Feng Chen
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Xu-Guang Xi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China.
- LBPA, Ecole Normale Supérieure Paris-Saclay, CNRS, Université Paris Saclay, 61, Avenue du Président Wilson, 94235, Cachan, France.
| | - Yong Xu
- Experimental Medicine Center, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
- Department of Endocrinology and Metabolism, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
- Cardiovascular and Metabolic Diseases Key Laboratory of Luzhou, and Sichuan Clinical Research Center for Nephropathy, and Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
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Largy E, König A, Ghosh A, Ghosh D, Benabou S, Rosu F, Gabelica V. Mass Spectrometry of Nucleic Acid Noncovalent Complexes. Chem Rev 2021; 122:7720-7839. [PMID: 34587741 DOI: 10.1021/acs.chemrev.1c00386] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nucleic acids have been among the first targets for antitumor drugs and antibiotics. With the unveiling of new biological roles in regulation of gene expression, specific DNA and RNA structures have become very attractive targets, especially when the corresponding proteins are undruggable. Biophysical assays to assess target structure as well as ligand binding stoichiometry, affinity, specificity, and binding modes are part of the drug development process. Mass spectrometry offers unique advantages as a biophysical method owing to its ability to distinguish each stoichiometry present in a mixture. In addition, advanced mass spectrometry approaches (reactive probing, fragmentation techniques, ion mobility spectrometry, ion spectroscopy) provide more detailed information on the complexes. Here, we review the fundamentals of mass spectrometry and all its particularities when studying noncovalent nucleic acid structures, and then review what has been learned thanks to mass spectrometry on nucleic acid structures, self-assemblies (e.g., duplexes or G-quadruplexes), and their complexes with ligands.
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Affiliation(s)
- Eric Largy
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Alexander König
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Anirban Ghosh
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Debasmita Ghosh
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Sanae Benabou
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Frédéric Rosu
- Univ. Bordeaux, CNRS, INSERM, IECB, UMS 3033, F-33600 Pessac, France
| | - Valérie Gabelica
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
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Ramos CIV, Monteiro AR, Moura NMM, Faustino MAF, Trindade T, Neves MGPMS. The Interactions of H 2TMPyP, Analogues and Its Metal Complexes with DNA G-Quadruplexes-An Overview. Biomolecules 2021; 11:biom11101404. [PMID: 34680037 PMCID: PMC8533071 DOI: 10.3390/biom11101404] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 09/16/2021] [Accepted: 09/22/2021] [Indexed: 12/26/2022] Open
Abstract
The evidence that telomerase is overexpressed in almost 90% of human cancers justifies the proposal of this enzyme as a potential target for anticancer drug design. The inhibition of telomerase by quadruplex stabilizing ligands is being considered a useful approach in anticancer drug design proposals. Several aromatic ligands, including porphyrins, were exploited for telomerase inhibition by adduct formation with G-Quadruplex (GQ). 5,10,15,20-Tetrakis(N-methyl-4-pyridinium)porphyrin (H2TMPyP) is one of the most studied porphyrins in this field, and although reported as presenting high affinity to GQ, its poor selectivity for GQ over duplex structures is recognized. To increase the desired selectivity, porphyrin modifications either at the peripheral positions or at the inner core through the coordination with different metals have been handled. Herein, studies involving the interactions of TMPyP and analogs with different DNA sequences able to form GQ and duplex structures using different experimental conditions and approaches are reviewed. Some considerations concerning the structural diversity and recognition modes of G-quadruplexes will be presented first to facilitate the comprehension of the studies reviewed. Additionally, considering the diversity of experimental conditions reported, we decided to complement this review with a screening where the behavior of H2TMPyP and of some of the reviewed metal complexes were evaluated under the same experimental conditions and using the same DNA sequences. In this comparison under unified conditions, we also evaluated, for the first time, the behavior of the AgII complex of H2TMPyP. In general, all derivatives showed good affinity for GQ DNA structures with binding constants in the range of 106–107 M−1 and ligand-GQ stoichiometric ratios of 3:1 and 4:1. A promising pattern of selectivity was also identified for the new AgII derivative.
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Affiliation(s)
- Catarina I. V. Ramos
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (A.R.M.); (N.M.M.M.); (M.A.F.F.); (M.G.P.M.S.N.)
- Correspondence: ; Tel.: +351-234-370-692
| | - Ana R. Monteiro
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (A.R.M.); (N.M.M.M.); (M.A.F.F.); (M.G.P.M.S.N.)
- CICECO-Aveiro, Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal;
| | - Nuno M. M. Moura
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (A.R.M.); (N.M.M.M.); (M.A.F.F.); (M.G.P.M.S.N.)
| | - Maria Amparo F. Faustino
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (A.R.M.); (N.M.M.M.); (M.A.F.F.); (M.G.P.M.S.N.)
| | - Tito Trindade
- CICECO-Aveiro, Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal;
| | - Maria Graça P. M. S. Neves
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (A.R.M.); (N.M.M.M.); (M.A.F.F.); (M.G.P.M.S.N.)
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Verma S, Ravichandiran V, Ranjan N. Beyond amyloid proteins: Thioflavin T in nucleic acid recognition. Biochimie 2021; 190:111-123. [PMID: 34118329 DOI: 10.1016/j.biochi.2021.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 05/25/2021] [Accepted: 06/04/2021] [Indexed: 01/01/2023]
Abstract
Thioflavin T (ThT) is a commercially available fluorescent dye that is commonly used in biomedical research for over five decades. It was first reported as an extrinsic fluorescent probe for the detection of amyloid fibrils and related processes and it has also been used extensively for assessing protein binding in fluorescence-based assays. Although the nucleic acid binding of ThT was reported half of a century ago in the 1970s, it was not widely explored until the start of this decade. In recent years, Thioflavin T has become a major tool in the recognition of many types of non-canonical nucleic acid conformations including duplexes, triplexes, and G-quadruplexes. The propensity of ThT binding is more towards base aberrations, bulges, and mismatches highlighting its importance in serving as a diagnostic tool in a variety of ailments/disease conditions. In this review, we cover major advancements in nucleic acid detection/binding by ThT to a variety of nucleic acid structures.
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Affiliation(s)
- Smita Verma
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER)-Raebareli, New Transit Campus, Lucknow, Uttar Pradesh, 226002, India; Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER)-Kolkata, Maniktala Main Road, Kolkata, 700054, India
| | - Velayutham Ravichandiran
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER)-Kolkata, Maniktala Main Road, Kolkata, 700054, India
| | - Nihar Ranjan
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER)-Raebareli, New Transit Campus, Lucknow, Uttar Pradesh, 226002, India.
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Ghosh A, Largy E, Gabelica V. DNA G-quadruplexes for native mass spectrometry in potassium: a database of validated structures in electrospray-compatible conditions. Nucleic Acids Res 2021; 49:2333-2345. [PMID: 33555347 PMCID: PMC7913678 DOI: 10.1093/nar/gkab039] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 12/22/2020] [Accepted: 01/19/2021] [Indexed: 02/07/2023] Open
Abstract
G-quadruplex DNA structures have become attractive drug targets, and native mass spectrometry can provide detailed characterization of drug binding stoichiometry and affinity, potentially at high throughput. However, the G-quadruplex DNA polymorphism poses problems for interpreting ligand screening assays. In order to establish standardized MS-based screening assays, we studied 28 sequences with documented NMR structures in (usually ∼100 mM) potassium, and report here their circular dichroism (CD), melting temperature (Tm), NMR spectra and electrospray mass spectra in 1 mM KCl/100 mM trimethylammonium acetate. Based on these results, we make a short-list of sequences that adopt the same structure in the MS assay as reported by NMR, and provide recommendations on using them for MS-based assays. We also built an R-based open-source application to build and consult a database, wherein further sequences can be incorporated in the future. The application handles automatically most of the data processing, and allows generating custom figures and reports. The database is included in the g4dbr package (https://github.com/EricLarG4/g4dbr) and can be explored online (https://ericlarg4.github.io/G4_database.html).
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Affiliation(s)
- Anirban Ghosh
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33000 Bordeaux, France
| | - Eric Largy
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33000 Bordeaux, France
| | - Valérie Gabelica
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33000 Bordeaux, France
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Balasubramanian S, Senapati S. Dynamics and Barrier of Movements of Sodium and Potassium Ions Across the Oxytricha nova G-Quadruplex Core. J Phys Chem B 2020; 124:11055-11066. [PMID: 33238706 DOI: 10.1021/acs.jpcb.0c04826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
G-quadruplexes (GQs) are highly stable noncanonical forms of nucleic acids that are present in important genomic regions. The central core of the GQ is lined up by four closely spaced carbonyl groups from the G-quartets, and the resulting electrostatic repulsion is neutralized by the coordinating cations. In spite of several reports on GQ structure and cation-GQ interactions, the atomic- to molecular-level understanding of the ion dynamics and ion exchange in the GQ core is quite poor. Here, we attempt to elucidate the mechanism of Na+ and K+ binding to the GQ core and trace the exchange of these ions with the ions in bulk by means of all-atomic molecular dynamics (MD) simulations. One of the most studied GQs, Oxytricha nova telomeric G-quadruplex (OxyGQ), is taken as the representative GQ. Subsequently, umbrella sampling MD simulations were performed to elucidate the energetics of ion translocation from one end to the other end of the GQ central core. Our study highlights the importance of ion hydration for the uptake and correct positioning of the cations in the core. The free-energy landscape of ion transport has shown favorable in-plane binding of Na+ ions with GQ quartets, which matches very well with the crystal structure. The binding of K+ ions, on the other hand, was out-of-plane and its translocation required a larger barrier to cross.
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Affiliation(s)
- Sangeetha Balasubramanian
- Department of Biotechnology, BJM School of Biosciences, Indian Institute of Technology Madras, Chennai 600 036, India
| | - Sanjib Senapati
- Department of Biotechnology, BJM School of Biosciences, Indian Institute of Technology Madras, Chennai 600 036, India
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11
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Cao Y, Yang L, Ding P, Li W, Pei R. Ligand Selectivity by Inserting GCGC‐Tetrads into G‐Quadruplex Structures. Chemistry 2020; 26:14730-14737. [DOI: 10.1002/chem.202003004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/22/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Yanwei Cao
- CAS Key Laboratory of Nano-Bio Interface Division of Nanobiomedicine Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 P. R. China
| | - Luyan Yang
- CAS Key Laboratory of Nano-Bio Interface Division of Nanobiomedicine Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 P. R. China
| | - Pi Ding
- CAS Key Laboratory of Nano-Bio Interface Division of Nanobiomedicine Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 P. R. China
| | - Wenjing Li
- CAS Key Laboratory of Nano-Bio Interface Division of Nanobiomedicine Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 P. R. China
| | - Renjun Pei
- CAS Key Laboratory of Nano-Bio Interface Division of Nanobiomedicine Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 P. R. China
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Ranjan N, Andreasen KF, Arora Y, Xue L, Arya DP. Surface Dependent Dual Recognition of a G-quadruplex DNA With Neomycin-Intercalator Conjugates. Front Chem 2020; 8:60. [PMID: 32117884 PMCID: PMC7028757 DOI: 10.3389/fchem.2020.00060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 01/20/2020] [Indexed: 01/17/2023] Open
Abstract
G-quadruplexes have been characterized as structures of vital importance in the cellular functioning of several life forms. They have subsequently been established to serve as a therapeutic target of several diseases including cancer, HIV, tuberculosis and malaria. In this paper, we report the binding of aminosugar-intercalator conjugates with a well-studied anti-parallel G-quadruplex derived from Oxytricha Nova G-quadruplex DNA. Of the four neomycin-intercalator conjugates studied with varying surface areas, BQQ-neomycin conjugate displayed the best binding to this DNA G-quadruplex structure with an association constant of Ka = (1.01 ±0.03) × 107 M−1 which is nearly 100-fold higher than the binding of neomycin to this quadruplex. The binding of BQQ-neomycin displays a binding stoichiometry of 1:1 indicating the presence of a single and unique binding site for this G-quadruplex. In contrast, the BQQ-neomycin displays very weak binding to the bacterial A-site rRNA sequence showing that BQQ-does not enhance the neomycin binding to its natural target, the bacterial rRNA A-site. The BQQ-neomycin conjugate is prone to aggregation even at low micromolar concentrations (4 μM) leading to some ambiguities in the analysis of thermal denaturation profiles. Circular dichroism experiments showed that binding of BQQ-neomycin conjugate causes some structural changes in the quadruplex while still maintaining the overall anti-parallel structure. Finally, the molecular docking experiments suggest that molecular surface plays an important role in the recognition of a second site on the G-quadruplex. Overall, these results show that molecules with more than one binding moieties can be made to specifically recognize G-quadruplexes with high affinities. The dual binding molecules comprise of quadruplex groove binding and intercalator units, and the molecular surface of the intercalator plays an important part in enhancing binding interaction to the G-quadruplex structure.
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Affiliation(s)
- Nihar Ranjan
- Laboratory for Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, SC, United States.,Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Raebareli, India
| | - Katrine F Andreasen
- Laboratory for Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, SC, United States
| | - Yashaswina Arora
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Raebareli, India
| | - Liang Xue
- Laboratory for Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, SC, United States
| | - Dev P Arya
- Laboratory for Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, SC, United States
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13
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Chan MS, Leung HM, Wong SW, Lin Z, Gao Q, Chang TJH, Lai KWC, Lo PK. Reversible reconfiguration of high-order DNA nanostructures by employing G-quartet toeholds as adhesive units. NANOSCALE 2020; 12:2464-2471. [PMID: 31915778 DOI: 10.1039/c9nr08070h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
G-quadruplex structures are becoming useful alternative interaction modules for the assembly of DNA nanomaterials because of their unique inducibility by cations. In this study, we demonstrated a new strategy for the assembly of polymeric DNA nanoarchitectures in the presence of cations, such as K+ and Na+, by employing G-quartet toeholds at the edges of discrete mini-square DNA building blocks as adhesive units. In comparison with the Watson-Crick base-paired duplex linkers, G-quadruplex arrays embedded in the self-assembled DNA system exhibit higher thermal stability. The morphology of these doughnut-shaped or spherical-shaped DNA nanostructures is highly regulated by the orientation of the folded G-quadruplexes either in parallel or antiparallel orientation in response to different cations. Furthermore, this G-quadruplex-mediated assembly strategy is able to manipulate the cycling of DNA assemblies between discrete and polymeric states by means of introducing cations and chelating agents sequentially. This property enables the reversible manipulation of the DNA-based nanosystems for at least 4 cycles. The G-quadruplex array embedded in this self-assembled DNA system can become a scaffold for functional molecules, as a number of organic molecules and proteins exhibit specific binding to these G-quadruplex structures. Besides, embedded G-quadruplexes are also considered as functional components of nanoscale electronic materials due to their electron transport through the stacked orientation of the G-quartet. Therefore, this work is an important step towards obtaining reversible, responsive G-quadruplex-induced DNA-based nanomaterials with versatile functionalities which will be highly useful in further electronic, biomedical and drug-delivery applications.
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Affiliation(s)
- Miu Shan Chan
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Hoi Man Leung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Sze Wing Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Zihong Lin
- Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Qi Gao
- Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Tristan Juin Han Chang
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - King Wai Chiu Lai
- Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Pik Kwan Lo
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China and Key Laboratory of Biochip Technology, Biotech and Health Care, Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518057, China.
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14
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Yett A, Lin LY, Beseiso D, Miao J, Yatsunyk LA. N-methyl mesoporphyrin IX as a highly selective light-up probe for G-quadruplex DNA. J PORPHYR PHTHALOCYA 2019; 23:1195-1215. [PMID: 34385812 PMCID: PMC8356643 DOI: 10.1142/s1088424619300179] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
N-methyl mesoporphyrin IX (NMM) is a water-soluble, non-symmetric porphyrin with excellent optical properties and unparalleled selectivity for G-quadruplex (GQ) DNA. G-quadruplexes are non-canonical DNA structures formed by guanine-rich sequences. They are implicated in genomic stability, longevity, and cancer. The ability of NMM to selectively recognize GQ structures makes it a valuable scaffold for designing novel GQ binders. In this review, we survey the literature describing the GQ-binding properties of NMM as well as its wide utility in chemistry and biology. We start with the discovery of the GQ-binding properties of NMM and the development of NMM-binding aptamers. We then discuss the optical properties of NMM, focusing on the light-switch effect - high fluorescence of NMM induced upon its binding to GQ DNA. Additionally, we examine the affinity and selectivity of NMM for GQs, as well as its ability to stabilize GQ structures and favor parallel GQ conformations. Furthermore, a portion of the review is dedicated to the applications of NMM-GQ complexes as biosensors for heavy metals, small molecules (e.g. ATP and pesticides), DNA, and proteins. Finally and importantly, we discuss the utility of NMM as a probe to investigate the roles of GQs in biological processes.
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Affiliation(s)
- Ariana Yett
- Swarthmore College, Department of Chemistry and Biochemistry, 500 College Ave, Swarthmore, PA 19081, USA
| | - Linda Yingqi Lin
- Swarthmore College, Department of Chemistry and Biochemistry, 500 College Ave, Swarthmore, PA 19081, USA
| | - Dana Beseiso
- Swarthmore College, Department of Chemistry and Biochemistry, 500 College Ave, Swarthmore, PA 19081, USA
| | - Joanne Miao
- Swarthmore College, Department of Chemistry and Biochemistry, 500 College Ave, Swarthmore, PA 19081, USA
| | - Liliya A. Yatsunyk
- Correspondence to: Liliya A. Yatsunyk, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA. tel.: 610-328-8558,
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15
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Zheng J, Du Y, Wang H, Peng P, Shi L, Li T. Ultrastable Bimolecular G-Quadruplexes Programmed DNA Nanoassemblies for Reconfigurable Biomimetic DNAzymes. ACS NANO 2019; 13:11947-11954. [PMID: 31589020 DOI: 10.1021/acsnano.9b06029] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The relatively low stability and polymorphism of bimolecular G-quadruplexes (bi-G4s) are big difficulties that are faced in employing them to guide DNA assembly, as they are usually subject to a transformation into more stable tetramolecular or G-wire structures favored by K+ or Mg2+. Although bi-G4s benefit by additional duplex handles, a challenge remains in tailoring their intrinsic properties to resolve the above difficulties. Toward this challenge, here we engineer several ultrastable bi-G4s via replacing their nucleotide loops with special mini-hairpins, which consist of a GAA loop and a short GC-paired stem. Such a structural alteration favors the formation of G:C:G:C tetrads in the head-to-head folding topologies of bi-G4s and improves their thermal stability, with an increase in the melting temperature by up to 25 °C. It dramatically reduces their structural conversion into G-wires, verified by atomic force microscopy. These features enable the utilization of two well-chosen bi-G4s to shape a DNA nanotriangle into the desired framework nucleic acid (FNA) architectures such as "bowknot" and "butterfly" that are reversibly switched by the bi-G4s. On this basis, we further build a reconfigurable DNAzyme device to mimic the activation of human telomerase that is modulated by the G4 dimerization. Our designed ultrastable bi-G4s will offer a promising tool for dynamically manipulating intracellular DNA nanoassemblies with endogenous K+ and exploring the relationship between dimerization and function in some physiological processes.
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Affiliation(s)
- Jiao Zheng
- Department of Chemistry , University of Science and Technology of China , 96 Jinzhai Road , Hefei , Anhui 230026 , China
| | - Yi Du
- Department of Chemistry , University of Science and Technology of China , 96 Jinzhai Road , Hefei , Anhui 230026 , China
| | - Huihui Wang
- Department of Chemistry , University of Science and Technology of China , 96 Jinzhai Road , Hefei , Anhui 230026 , China
| | - Pai Peng
- Department of Chemistry , University of Science and Technology of China , 96 Jinzhai Road , Hefei , Anhui 230026 , China
| | - Lili Shi
- Department of Chemistry , University of Science and Technology of China , 96 Jinzhai Road , Hefei , Anhui 230026 , China
| | - Tao Li
- Department of Chemistry , University of Science and Technology of China , 96 Jinzhai Road , Hefei , Anhui 230026 , China
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16
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Wan C, Fu W, Jing H, Zhang N. NMR solution structure of an asymmetric intermolecular leaped V-shape G-quadruplex: selective recognition of the d(G2NG3NG4) sequence motif by a short linear G-rich DNA probe. Nucleic Acids Res 2019; 47:1544-1556. [PMID: 30445650 PMCID: PMC6379650 DOI: 10.1093/nar/gky1167] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/01/2018] [Accepted: 11/04/2018] [Indexed: 02/07/2023] Open
Abstract
Aside from classical loops among G-quadruplexes, the unique leaped V-shape scaffold spans over three G-tetrads, without any intervening residues. This scaffold enables a sharp reversal of two adjacent strand directions and simultaneously participates in forming the G-tetrad core. These features make this scaffold itself distinctive and thus an essentially more accessible target. As an alternative to the conventional antisense method using a complementary chain, forming an intermolecular G-quadruplex from two different oligomers, in which the longer one as the target is captured by a short G-rich fragment, could be helpful for recognizing G-rich sequences and structural motifs. However, such an intermolecular leaped V-shape G-quadruplex consisting of DNA oligomers of quite different lengths has not been evaluated. Here, we present the first nuclear magnetic resonance (NMR) study of an asymmetric intermolecular leaped V-shape G-quadruplex assembled between an Oxytricha nova telomeric sequence d(G2T4G4T4G4) and a single G-tract fragment d(TG4A). Furthermore, we explored the selectivity of this short fragment as a potential probe, examined the kinetic discrimination for probing a specific mutant, and proposed the key sequence motif d(G2NG3NG4) essential for building the leaped V-shape G-quadruplexes.
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Affiliation(s)
- Chanjuan Wan
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Wenqiang Fu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Haitao Jing
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Na Zhang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.,Key Laboratory of Anhui Province for High Field Magnetic Resonance Imaging, Hefei 230031, China
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17
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Parasitic Protozoa: Unusual Roles for G-Quadruplexes in Early-Diverging Eukaryotes. Molecules 2019; 24:molecules24071339. [PMID: 30959737 PMCID: PMC6480360 DOI: 10.3390/molecules24071339] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 12/17/2022] Open
Abstract
Guanine-quadruplex (G4) motifs, at both the DNA and RNA levels, have assumed an important place in our understanding of the biology of eukaryotes, bacteria and viruses. However, it is generally little known that their very first description, as well as the foundational work on G4s, was performed on protozoans: unicellular life forms that are often parasitic. In this review, we provide a historical perspective on the discovery of G4s, intertwined with their biological significance across the protozoan kingdom. This is a history in three parts: first, a period of discovery including the first characterisation of a G4 motif at the DNA level in ciliates (environmental protozoa); second, a period less dense in publications concerning protozoa, during which DNA G4s were discovered in both humans and viruses; and third, a period of renewed interest in protozoa, including more mechanistic work in ciliates but also in pathogenic protozoa. This last period has opened an exciting prospect of finding new anti-parasitic drugs to interfere with parasite biology, thus adding new compounds to the therapeutic arsenal.
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18
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Ramos CIV, Almeida SP, Lourenço LMO, Pereira PMR, Fernandes R, Faustino MAF, Tomé JPC, Carvalho J, Cruz C, Neves MGPMS. Multicharged Phthalocyanines as Selective Ligands for G-Quadruplex DNA Structures. Molecules 2019; 24:E733. [PMID: 30781675 PMCID: PMC6412362 DOI: 10.3390/molecules24040733] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 02/12/2019] [Accepted: 02/13/2019] [Indexed: 01/21/2023] Open
Abstract
The stabilization of G-Quadruplex DNA structures by ligands is a promising strategy for telomerase inhibition in cancer therapy since this enzyme is responsible for the unlimited proliferation of cancer cells. To assess the potential of a compound as a telomerase inhibitor, selectivity for quadruplex over duplex DNA is a fundamental attribute, as the drug must be able to recognize quadruplex DNA in the presence of a large amount of duplex DNA, in the cellular nucleus. By using different spectroscopic techniques, such as ultraviolet-visible, fluorescence and circular dichroism, this work evaluates the potential of a series of multicharged phthalocyanines, bearing four or eight positive charges, as G-Quadruplex stabilizing ligands. This work led us to conclude that the existence of a balance between the number and position of the positive charges in the phthalocyanine structure is a fundamental attribute for its selectivity for G-Quadruplex structures over duplex DNA structures. Two of the studied phthalocyanines, one with four peripheral positive charges (ZnPc1) and the other with less exposed eight positive charges (ZnPc4) showed high selectivity and affinity for G-Quadruplex over duplex DNA structures and were able to accumulate in the nucleus of UM-UC-3 bladder cancer cells.
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Affiliation(s)
- Catarina I V Ramos
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Susana P Almeida
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Leandro M O Lourenço
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Patrícia M R Pereira
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal.
- CNC.IBILI Consortium, University of Coimbra, 3000-548 Coimbra, Portugal.
| | - Rosa Fernandes
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal.
- CNC.IBILI Consortium, University of Coimbra, 3000-548 Coimbra, Portugal.
| | - M Amparo F Faustino
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - João P C Tomé
- CQE & Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, n1, 1049-001 Lisboa, Portugal.
| | - Josué Carvalho
- CICS-UBI-Centro de Investigação em Ciências da Saúde, Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal.
| | - Carla Cruz
- CICS-UBI-Centro de Investigação em Ciências da Saúde, Universidade da Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal.
| | - M Graça P M S Neves
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
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19
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Giambasu GM, Case DA, York DM. Predicting Site-Binding Modes of Ions and Water to Nucleic Acids Using Molecular Solvation Theory. J Am Chem Soc 2019; 141:2435-2445. [PMID: 30632365 PMCID: PMC6574206 DOI: 10.1021/jacs.8b11474] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Site binding of ions and water shapes nucleic acids folding, dynamics, and biological function, complementing the more diffuse, nonspecific "territorial" ion binding. Unlike territorial binding, prediction of site-specific binding to nucleic acids remains an unsolved challenge in computational biophysics. This work presents a new toolset based on the 3D-RISM molecular solvation theory and topological analysis that predicts cation and water site binding to nucleic acids. 3D-RISM is shown to accurately capture alkali cations and water binding to the central channel, transversal loops, and grooves of the Oxytricha nova's telomeres' G-quadruplex ( Oxy-GQ), in agreement with high-resolution crystallographic data. To improve the computed cation occupancy along the Oxy-GQ central channel, it was necessary to refine and validate new cation-oxygen parameters using structural and thermodynamic data available for crown ethers and ion channels. This single set of parameters that describes both localized and delocalized binding to various biological systems is used to gain insight into cation occupancy along the Oxy-GQ channel under various salt conditions. The paper concludes with prospects for extending the method to predict divalent cation binding to nucleic acids. This work advances the forefront of theoretical methods able to provide predictive insight into ion atmosphere effects on nucleic acids function.
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Affiliation(s)
- George M. Giambasu
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - David A. Case
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Darrin M. York
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
- Laboratory for Biomolecular Simulation Research, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
- Center for Integrative Proteomics Research, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
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20
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Lu C, Smith-Carpenter JE, Taylor JSA. Evidence for Reverse Hoogsteen Hairpin Intermediates in the Photocrosslinking of Human Telomeric DNA Sequences. Photochem Photobiol 2018; 94:685-697. [PMID: 29418001 DOI: 10.1111/php.12898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 01/04/2018] [Indexed: 12/28/2022]
Abstract
UVB irradiation of human telomeric d(GGGTTA)3 GGG sequences in potassium ion solution crosslinks the first and third TTA segments through anti cyclobutane pyrimidine dimer (CPD) formation. The photocrosslinking reaction was first proposed to occur through a form 3 two-tetrad G-quadruplex in which the lateral four-nucleotide GTTA loop can interact with an adjacent TTA loop. Curiously, the reaction does not occur with sodium ion, which was explained by the formation of a basket structure which only has three-nucleotide TTA loops that cannot interact. Sequences known or expected to favor the two-tetrad basket did not show enhanced photocrosslinking, suggesting that some other structure was the reactive intermediate. Herein, we report that anti CPDs form in human telomeric DNA sequences with lithium ion that is known to disfavor G-quadruplex formation, as well as with potassium ion when the bases are modified to interfere with G-quartet formation. We also show that anti CPDs form in sequences containing A's in place of G's that cannot form Hoogsteen hairpins, but can form reverse Hoogsteen hairpins. These results suggest that reverse Hoogsteen hairpins may play a hitherto unrecognized role in the biology and photoreactivity of DNA in telomeres, and possibly in other purine-rich sequences found in regulatory regions.
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Affiliation(s)
- Chen Lu
- Department of Chemistry, Washington University, St. Louis, MO
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21
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Sagi J. In What Ways Do Synthetic Nucleotides and Natural Base Lesions Alter the Structural Stability of G-Quadruplex Nucleic Acids? J Nucleic Acids 2017; 2017:1641845. [PMID: 29181193 PMCID: PMC5664352 DOI: 10.1155/2017/1641845] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/15/2017] [Indexed: 01/03/2023] Open
Abstract
Synthetic analogs of natural nucleotides have long been utilized for structural studies of canonical and noncanonical nucleic acids, including the extensively investigated polymorphic G-quadruplexes (GQs). Dependence on the sequence and nucleotide modifications of the folding landscape of GQs has been reviewed by several recent studies. Here, an overview is compiled on the thermodynamic stability of the modified GQ folds and on how the stereochemical preferences of more than 70 synthetic and natural derivatives of nucleotides substituting for natural ones determine the stability as well as the conformation. Groups of nucleotide analogs only stabilize or only destabilize the GQ, while the majority of analogs alter the GQ stability in both ways. This depends on the preferred syn or anti N-glycosidic linkage of the modified building blocks, the position of substitution, and the folding architecture of the native GQ. Natural base lesions and epigenetic modifications of GQs explored so far also stabilize or destabilize the GQ assemblies. Learning the effect of synthetic nucleotide analogs on the stability of GQs can assist in engineering a required stable GQ topology, and exploring the in vitro action of the single and clustered natural base damage on GQ architectures may provide indications for the cellular events.
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Affiliation(s)
- Janos Sagi
- Rimstone Laboratory, RLI, Carlsbad, CA 92010, USA
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22
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Lecours MJ, Marchand A, Anwar A, Guetta C, Hopkins WS, Gabelica V. What stoichiometries determined by mass spectrometry reveal about the ligand binding mode to G-quadruplex nucleic acids. Biochim Biophys Acta Gen Subj 2017; 1861:1353-1361. [PMID: 28087374 DOI: 10.1016/j.bbagen.2017.01.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Revised: 01/06/2017] [Accepted: 01/09/2017] [Indexed: 11/27/2022]
Abstract
G-quadruplexes (G4s) have become important drug targets to regulate gene expression and telomere maintenance. Many studies on G4 ligand binding focus on determining the ligand binding affinities and selectivities. Ligands, however, can also affect the G4 conformation. Here we explain how to use electrospray ionization mass spectrometry (ESI-MS) to monitor simultaneously ligand binding and cation binding stoichiometries. The changes in potassium binding stoichiometry upon ligand binding hint at ligand-induced conformational changes involving a modification of the number of G-quartets. We investigated the interaction of three quadruplex ligands (PhenDC3, 360A and Pyridostatin) with a variety of G4s. Electrospray mass spectrometry makes it easy to detect K+ displacement (interpreted as quartet disruption) upon ligand binding, and to determine how many ligand molecules must be bound for the quartet opening to occur. The reasons for ligand-induced conversion to antiparallel structures with fewer quartets are discussed. Conversely, K+ intake (hence quartet formation) was detected upon ligand binding to G-rich sequences that did not form quadruplexes in 1mM K+ alone. This demonstrates the value of mass spectrometry for assessing not only ligand binding, but also ligand-induced rearrangements in the target sequence. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio.
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Affiliation(s)
- Michael J Lecours
- Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Adrien Marchand
- INSERM, CNRS, Université de Bordeaux, Laboratoire Acides Nucléiques: Régulations Naturelle et Artificielle (ARNA, U1212, UMR5320), IECB, 2 rue Robert Escarpit, 33607 Pessac, France
| | - Ahdia Anwar
- Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Corinne Guetta
- Institut Curie, CNRS, INSERM, Univ. Paris Sud, Laboratoire de Chimie, modélisation et imagerie pour la biologie (CMIB, U1196, UMR9187), Orsay, France
| | - W Scott Hopkins
- Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Valérie Gabelica
- INSERM, CNRS, Université de Bordeaux, Laboratoire Acides Nucléiques: Régulations Naturelle et Artificielle (ARNA, U1212, UMR5320), IECB, 2 rue Robert Escarpit, 33607 Pessac, France.
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23
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Ruan TL, Davis SJ, Powell BM, Harbeck CP, Habdas J, Habdas P, Yatsunyk LA. Lowering the overall charge on TMPyP4 improves its selectivity for G-quadruplex DNA. Biochimie 2017; 132:121-130. [DOI: 10.1016/j.biochi.2016.11.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Accepted: 11/07/2016] [Indexed: 12/24/2022]
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24
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Mandal PK, Baptiste B, Langlois d'Estaintot B, Kauffmann B, Huc I. Multivalent Interactions between an Aromatic Helical Foldamer and a DNA G-Quadruplex in the Solid State. Chembiochem 2016; 17:1911-1914. [DOI: 10.1002/cbic.201600281] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Indexed: 01/20/2023]
Affiliation(s)
- Pradeep K. Mandal
- University of Bordeaux; CBMN; UMR 5248); Institut Européen de Chimie et Biologie; 2 rue Escarpit 33600 Pessac France
- CNRS; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
- Bordeaux Institut National Polytechnique; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
| | - Benoît Baptiste
- University of Bordeaux; CBMN; UMR 5248); Institut Européen de Chimie et Biologie; 2 rue Escarpit 33600 Pessac France
- CNRS; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
- Bordeaux Institut National Polytechnique; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
| | - Béatrice Langlois d'Estaintot
- University of Bordeaux; CBMN; UMR 5248); Institut Européen de Chimie et Biologie; 2 rue Escarpit 33600 Pessac France
- CNRS; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
- Bordeaux Institut National Polytechnique; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
| | - Brice Kauffmann
- University of Bordeaux; IECB; UMS 3033); Institut Européen de Chimie et Biologie; 2 rue Escarpit 33600 Pessac France
- CNRS; IECB; UMS 3033); 2 rue Escarpit 33600 Pessac France
- INSERM; IECB; US001); 2 rue Escarpit 33600 Pessac France
| | - Ivan Huc
- University of Bordeaux; CBMN; UMR 5248); Institut Européen de Chimie et Biologie; 2 rue Escarpit 33600 Pessac France
- CNRS; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
- Bordeaux Institut National Polytechnique; CBMN; UMR 5248); 2 rue Escarpit 33600 Pessac France
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25
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Marchand A, Strzelecka D, Gabelica V. Selective and Cooperative Ligand Binding to Antiparallel Human Telomeric DNA G-Quadruplexes. Chemistry 2016; 22:9551-5. [PMID: 27168452 DOI: 10.1002/chem.201601937] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Indexed: 01/16/2023]
Abstract
The quest for ligands that specifically bind to particular G-quadruplex nucleic acid structures is particularly important to conceive molecules with specific effects on gene expression or telomere maintenance, or conceive structure-specific molecular probes. Using electrospray mass spectrometry in native conditions, we reveal a highly cooperative and selective 2:1 binding of Cu(II) -tolylterpyridine complexes to human telomeric G-quadruplexes. Circular dichroism and comparisons of affinities for different sequences reveal a marked preference for antiparallel structures with diagonal loops and/or wide-medium-narrow-medium groove-width order. The cooperativity is attributed to conformational changes in the polymorphic telomeric G-quadruplex sequences, which convert preferably into an antiparallel three-quartet topology upon binding of two ligands.
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Affiliation(s)
- Adrien Marchand
- Université de Bordeaux, IECB, ARNA Laboratory, 33600, Pessac, France.,Inserm, U1212, ARNA Laboratory, 33000, Bordeaux, France.,CNRS, UMR 5320, ARNA Laboratory, 33400, Talence, France
| | - Dominika Strzelecka
- Université de Bordeaux, IECB, ARNA Laboratory, 33600, Pessac, France.,Inserm, U1212, ARNA Laboratory, 33000, Bordeaux, France.,Division of Biophysics, Institute of Experimental Physics, University of Warsaw, Warsaw, Poland
| | - Valerie Gabelica
- Université de Bordeaux, IECB, ARNA Laboratory, 33600, Pessac, France. .,Inserm, U1212, ARNA Laboratory, 33000, Bordeaux, France. .,CNRS, UMR 5320, ARNA Laboratory, 33400, Talence, France.
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Largy E, Mergny JL, Gabelica V. Role of Alkali Metal Ions in G-Quadruplex Nucleic Acid Structure and Stability. Met Ions Life Sci 2016; 16:203-58. [PMID: 26860303 DOI: 10.1007/978-3-319-21756-7_7] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
G-quadruplexes are guanine-rich nucleic acids that fold by forming successive quartets of guanines (the G-tetrads), stabilized by intra-quartet hydrogen bonds, inter-quartet stacking, and cation coordination. This specific although highly polymorphic type of secondary structure deviates significantly from the classical B-DNA duplex. G-quadruplexes are detectable in human cells and are strongly suspected to be involved in a number of biological processes at the DNA and RNA levels. The vast structural polymorphism exhibited by G-quadruplexes, together with their putative biological relevance, makes them attractive therapeutic targets compared to canonical duplex DNA. This chapter focuses on the essential and specific coordination of alkali metal cations by G-quadruplex nucleic acids, and most notably on studies highlighting cation-dependent dissimilarities in their stability, structure, formation, and interconversion. Section 1 surveys G-quadruplex structures and their interactions with alkali metal ions while Section 2 presents analytical methods used to study G-quadruplexes. The influence of alkali cations on the stability, structure, and kinetics of formation of G-quadruplex structures of quadruplexes will be discussed in Sections 3 and 4. Section 5 focuses on the cation-induced interconversion of G-quadruplex structures. In Sections 3 to 5, we will particularly emphasize the comparisons between cations, most often K(+) and Na(+) because of their prevalence in the literature and in cells.
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Affiliation(s)
- Eric Largy
- ARNA Laboratory, Université Bordeaux, IECB, 2, rue Robert Escarpit, F-33600, Pessac, France.,ARNA Laboratory, INSERM, U869, F-33000, Bordeaux, France
| | - Jean-Louis Mergny
- ARNA Laboratory, Université Bordeaux, IECB, 2, rue Robert Escarpit, F-33600, Pessac, France. .,ARNA Laboratory, INSERM, U869, F-33000, Bordeaux, France.
| | - Valérie Gabelica
- ARNA Laboratory, Université Bordeaux, IECB, 2, rue Robert Escarpit, F-33600, Pessac, France. .,ARNA Laboratory, INSERM, U869, F-33000, Bordeaux, France.
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Ang DL, Harper BWJ, Cubo L, Mendoza O, Vilar R, Aldrich-Wright J. Quadruplex DNA-Stabilising Dinuclear Platinum(II) Terpyridine Complexes with Flexible Linkers. Chemistry 2015; 22:2317-25. [PMID: 26670391 DOI: 10.1002/chem.201503663] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Indexed: 12/19/2022]
Abstract
Four dinuclear terpyridineplatinum(II) (Pt-terpy) complexes were investigated for interactions with G-quadruplex DNA (QDNA) and duplex DNA (dsDNA) by synchrotron radiation circular dichroism (SRCD), fluorescent intercalator displacement (FID) assays and fluorescence resonance energy transfer (FRET) melting studies. Additionally, computational docking studies were undertaken to provide insight into potential binding modes for these complexes. The complexes demonstrated the ability to increase the melting temperature of various QDNA motifs by up to 17 °C and maintain this in up to a 600-fold excess of dsDNA. This study demonstrates that dinuclear Pt-terpy complexes stabilise QDNA and have a high degree of selectivity for QDNA over dsDNA.
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Affiliation(s)
- Dale L Ang
- Nanoscale Organisation and Dynamics Group, School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia
| | - Benjamin W J Harper
- Nanoscale Organisation and Dynamics Group, School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia
| | - Leticia Cubo
- Department of Chemistry, Imperial College London, London, SW7 2AZ, UK
| | - Oscar Mendoza
- Department of Chemistry, Imperial College London, London, SW7 2AZ, UK
| | - Ramon Vilar
- Department of Chemistry, Imperial College London, London, SW7 2AZ, UK.,Institute of Chemical Biology, Imperial College London, London, SW7 2AZ, UK
| | - Janice Aldrich-Wright
- Nanoscale Organisation and Dynamics Group, School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia.
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Brčić J, Plavec J. Solution structure of a DNA quadruplex containing ALS and FTD related GGGGCC repeat stabilized by 8-bromodeoxyguanosine substitution. Nucleic Acids Res 2015; 43:8590-600. [PMID: 26253741 PMCID: PMC4787828 DOI: 10.1093/nar/gkv815] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 07/30/2015] [Indexed: 12/13/2022] Open
Abstract
A prolonged expansion of GGGGCC repeat within non-coding region of C9orf72 gene has been identified as the most common cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), which are devastating neurodegenerative disorders. Formation of unusual secondary structures within expanded GGGGCC repeat, including DNA and RNA G-quadruplexes and R-loops was proposed to drive ALS and FTD pathogenesis. Initial NMR investigation on DNA oligonucleotides with four repeat units as the shortest model with the ability to form an unimolecular G-quadruplex indicated their folding into multiple G-quadruplex structures in the presence of K+ ions. Single dG to 8Br-dG substitution at position 21 in oligonucleotide d[(G4C2)3G4] and careful optimization of folding conditions enabled formation of mostly a single G-quadruplex species, which enabled determination of a high-resolution structure with NMR. G-quadruplex structure adopted by d[(G4C2)3GGBrGG] is composed of four G-quartets, which are connected by three edgewise C-C loops. All four strands adopt antiparallel orientation to one another and have alternating syn-anti progression of glycosidic conformation of guanine residues. One of the cytosines in every loop is stacked upon the G-quartet contributing to a very compact and stable structure.
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Affiliation(s)
- Jasna Brčić
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000, Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000, Ljubljana, Slovenia Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia EN-FIST Center of Excellence, Ljubljana, Slovenia
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Zhu H, Xiao S, Wang L, Liang H. Communication: Asymmetrical cation movements through G-quadruplex DNA. J Chem Phys 2014; 141:041103. [DOI: 10.1063/1.4891218] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Hong Zhu
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Shiyan Xiao
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Lei Wang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Haojun Liang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Hefei National Laboratory for Physical Sciences at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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Sabharwal NC, Savikhin V, Turek-Herman JR, Nicoludis JM, Szalai VA, Yatsunyk LA. N-methylmesoporphyrin IX fluorescence as a reporter of strand orientation in guanine quadruplexes. FEBS J 2014; 281:1726-37. [PMID: 24494857 PMCID: PMC4163640 DOI: 10.1111/febs.12734] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 12/24/2013] [Accepted: 01/30/2014] [Indexed: 11/30/2022]
Abstract
Guanine quadruplexes (GQ) are four-stranded DNA structures formed by guanine-rich DNA sequences. The formation of GQs inhibits cancer cell growth, although the detection of GQs in vivo has proven difficult, in part because of their structural diversity. The development of GQ-selective fluorescent reporters would enhance our ability to quantify the number and location of GQs, ultimately advancing biological studies of quadruplex relevance and function. N-methylmesoporphyrin IX (NMM) interacts selectively with parallel-stranded GQs; in addition, its fluorescence is sensitive to the presence of DNA, making this ligand a possible candidate for a quadruplex probe. In the present study, we investigated the effect of DNA secondary structure on NMM fluorescence. We found that NMM fluorescence increases by about 60-fold in the presence of parallel-stranded GQs and by about 40-fold in the presence of hybrid GQs. Antiparallel GQs lead to lower than 10-fold increases in NMM fluorescence. Single-stranded DNA, duplex, or i-motif, induce no change in NMM fluorescence. We conclude that NMM shows promise as a 'turn-on' fluorescent probe for detecting quadruplex structures, as well as for differentiating them on the basis of strand orientation.
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Affiliation(s)
- Navin C Sabharwal
- Department of Chemistry and Biochemistry, Swarthmore College, PA, USA
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Chen C, Zhou L, Geng J, Ren J, Qu X. Photosensitizer-incorporated quadruplex DNA-gated nanovechicles for light-triggered, targeted dual drug delivery to cancer cells. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:2793-2653. [PMID: 23341257 DOI: 10.1002/smll.201201916] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 11/25/2012] [Indexed: 06/01/2023]
Abstract
A novel light-operated vehicle for targeted intracellular drug delivery is constructed using photosensitizer-incorporated G-quadruplex DNA-capped mesoporous silica nanoparticles. Upon light irradiation, the photosensitizer generates ROS, causing the DNA capping to be cleaved and allowing cargo to be released. Importantly, this platform makes it possible to develop a drug-carrier system for the synergistic combination of chemotherapy and PDT for cancer treatment with spatial/temporal control. Furthermore, the introducing of targeting ligands further improves tumor targeting efficiency. The excellent biocompatibility, cell-specific intracellular drug delivery, and cellular uptake properties set up the basis for future biomedical application that require in vivo controlled, targeted drug delivery.
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Affiliation(s)
- Cuie Chen
- State Key Laboratory of Rare, Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China
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Čech P, Kukal J, Černý J, Schneider B, Svozil D. Automatic workflow for the classification of local DNA conformations. BMC Bioinformatics 2013; 14:205. [PMID: 23800225 PMCID: PMC3694522 DOI: 10.1186/1471-2105-14-205] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 05/28/2013] [Indexed: 12/03/2022] Open
Abstract
Background A growing number of crystal and NMR structures reveals a considerable structural polymorphism of DNA architecture going well beyond the usual image of a double helical molecule. DNA is highly variable with dinucleotide steps exhibiting a substantial flexibility in a sequence-dependent manner. An analysis of the conformational space of the DNA backbone and the enhancement of our understanding of the conformational dependencies in DNA are therefore important for full comprehension of DNA structural polymorphism. Results A detailed classification of local DNA conformations based on the technique of Fourier averaging was published in our previous work. However, this procedure requires a considerable amount of manual work. To overcome this limitation we developed an automatic classification method consisting of the combination of supervised and unsupervised approaches. A proposed workflow is composed of k-NN method followed by a non-hierarchical single-pass clustering algorithm. We applied this workflow to analyze 816 X-ray and 664 NMR DNA structures released till February 2013. We identified and annotated six new conformers, and we assigned four of these conformers to two structurally important DNA families: guanine quadruplexes and Holliday (four-way) junctions. We also compared populations of the assigned conformers in the dataset of X-ray and NMR structures. Conclusions In the present work we developed a machine learning workflow for the automatic classification of dinucleotide conformations. Dinucleotides with unassigned conformations can be either classified into one of already known 24 classes or they can be flagged as unclassifiable. The proposed machine learning workflow permits identification of new classes among so far unclassifiable data, and we identified and annotated six new conformations in the X-ray structures released since our previous analysis. The results illustrate the utility of machine learning approaches in the classification of local DNA conformations.
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Affiliation(s)
- Petr Čech
- Laboratory of Informatics and Chemistry, ICT Prague, Technická 5, Prague 6, 166 28, Czech Republic
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Abstract
The folding of various intra- and intermolecular i-motif DNAs is systematically studied to expand the toolbox for the control of mechanical operations in DNA nanoarchitectures. We analyzed i-motif DNAs with two C-tracts under acidic conditions by gel electrophoresis, circular dichroism, and thermal denaturation and show that their intra- versus intermolecular folding primarily depends on the length of the C-tracts. Two stretches of six or fewer C-residues favor the intermolecular folding of i-motifs, whereas longer C-tracts promote the formation of intramolecular i-motif structures with unusually high thermal stability. We then introduced intra- and intermolecular i-motifs formed by DNAs containing two C-tracts into single-stranded regions within otherwise double-stranded DNA nanocircles. By adjusting the length of C-tracts we can control the intra- and intermolecular folding of i-motif DNAs and achieve programmable functionalization of dsDNA nanocircles. Single-stranded gaps in the nanocircle that are functionalized with an intramolecular i-motif enable the reversible contraction and extension of the DNA circle, as monitored by fluorescence quenching. Thereby, the nanocircle behaves as a proton-fueled DNA prototype machine. In contrast, nanorings containing intermolecular i-motifs induce the assembly of defined multicomponent DNA architectures in response to proton-triggered predicted structural changes, such as dimerization, "kiss", and cyclization. The resulting DNA nanostructures are verified by gel electrophoresis and visualized by atomic force microscopy, including different folding topologies of an intermolecular i-motif. The i-motif-functionalized DNA nanocircles may serve as a versatile tool for the formation of larger interlocked dsDNA nanostructures, like rotaxanes and catenanes, to achieve diverse mechanical operations.
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Affiliation(s)
- Tao Li
- Life and Medical Science (LIMES) Institute, Program Unit Chemical Biology and Medicinal Chemistry, University of Bonn, 53121 Bonn, Germany
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Abstract
G-quadruplexes constitute a class of nucleic acid structures defined by stacked guanine tetrads (or G-tetrads) with guanine bases from neighboring tetrads stacking with one another within the G-tetrad core. Individual G-quadruplexes can also stack with one another at their G-tetrad interface leading to higher-order structures as observed in telomeric repeat-containing DNA and RNA. In this study, we investigate how guanine base stacking influences the stability of G-quadruplexes and their stacked higher-order structures. A structural survey of the Protein Data Bank is conducted to characterize experimentally observed guanine base stacking geometries within the core of G-quadruplexes and at the interface between stacked G-quadruplex structures. We couple this survey with a systematic computational examination of stacked G-tetrad energy landscapes using quantum mechanical computations. Energy calculations of stacked G-tetrads reveal large energy differences of up to 12 kcal/mol between experimentally observed geometries at the interface of stacked G-quadruplexes. Energy landscapes are also computed using an AMBER molecular mechanics description of stacking energy and are shown to agree quite well with quantum mechanical calculated landscapes. Molecular dynamics simulations provide a structural explanation for the experimentally observed preference of parallel G-quadruplexes to stack in a 5′–5′ manner based on different accessible tetrad stacking modes at the stacking interfaces of 5′–5′ and 3′–3′ stacked G-quadruplexes.
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Affiliation(s)
- Christopher Jacques Lech
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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Benda L, Straka M, Sychrovský V, Bouř P, Tanaka Y. Detection of mercury-TpT dinucleotide binding by Raman spectra: a computational study. J Phys Chem A 2012; 116:8313-20. [PMID: 22803635 DOI: 10.1021/jp3045077] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Hg(2+) ion stabilizes the thymine-thymine mismatched base pair and provides new ways of creating various DNA structures. Recently, such T-Hg-T binding was detected by the Raman spectroscopy. In this work, detailed differences in vibrational frequencies and Raman intensity patterns in the free TpT dinucleotide and its metal-mediated complex (TpT·Hg)(2) are interpreted on the basis of quantum chemical modeling. The computations verified specific marker Raman bands indicating the effect of mercury binding to DNA. Although the B3LYP functional well-describes the Raman frequencies, a dispersion correction had to be added for all atoms including mercury to obtain realistic geometry of the (TpT·Hg)(2) dimer. Only then, the DFT complex structure agreed with those obtained with the wave function-based MP2 method. The aqueous solvent modeled as a polarizable continuum had a minor effect on the dispersion interaction, but it stabilized conformations of the sugar and phosphate parts. A generalized definition of internal coordinate force field was introduced to monitor covalent bond mechanical strengthening and weakening upon the Hg(2+) binding. Induced vibrational frequency shifts were rationalized in terms of changes in electronic structure. The simulations thus also provided reliable insight into the complex structure and stability.
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Affiliation(s)
- Ladislav Benda
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Praha 6, Czech Republic
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Abstract
G-quartets are square planar arrangements of four guanine bases, which can form extraordinarily stable stacks when present in nucleic acid sequences. Such G-quadruplex structures were long regarded as an in vitro phenomenon, but the widespread presence of suitable sequences in genomes and the identification of proteins that stabilize, modify or resolve these nucleic acid structures have provided circumstantial evidence for their physiological relevance. The therapeutic potential of small molecules that can stabilize or disrupt G-quadruplex structures has invigorated the field in recent years. Here we review some of the key observations that support biological functions for G-quadruplex DNA as well as the techniques and tools that have enabled researchers to probe these structures and their interactions with proteins and small molecules.
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Affiliation(s)
- Tracy M Bryan
- Children's Medical Research Institute, University of Sydney, 214 Hawkesbury Road, Westmead, Sydney, NSW 2145, Australia.
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Abstract
Metal ions stabilize quadruplex nucleic acids by coordinating the O6 guanine atoms from G-quartets. These quartets form the basic motif of quadruplex structures. This article systematically surveys the available crystallographic data on native quadruplexes, their ligand complexes and (in one instance) a protein complex. Three categories of quadruplex are examined, tetramolecular, bimolecular, and intramolecular: all are formed by telomeric nucleic acid sequences from human or ciliate organisms.
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Affiliation(s)
- Nancy H Campbell
- The School of Pharmacy, University of London, London, WC1N 1AX, UK
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Molecular dynamic and quantum mechanics study of drug recognition for the extremity of DNA G-quadruplex groove. Med Chem Res 2011. [DOI: 10.1007/s00044-011-9927-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Dailidonis VV, Danilov VI, Früchtl HA, van Mourik T. The nature of base stacking: a Monte Carlo study. Theor Chem Acc 2011. [DOI: 10.1007/s00214-011-1046-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Andrushchenko V, Tsankov D, Krasteva M, Wieser H, Bour P. Spectroscopic detection of DNA quadruplexes by vibrational circular dichroism. J Am Chem Soc 2011; 133:15055-64. [PMID: 21823674 DOI: 10.1021/ja204630k] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The four-stranded G-quadruplex motif is a conformation frequently adopted by guanine-rich nucleic acids that plays an important role in biology, medicine, and nanotechnology. Although vibrational spectroscopy has been widely used to investigate nucleic acid structure, association of particular spectral features with the quadruplex structure has to date been ambiguous. In this work, experimental IR absorption and vibrational circular dichroism (VCD) spectra of the model quadruplex systems d(G)(8) and deoxyguanosine-5'-monophosphate (5'-dGMP) were analyzed using molecular dynamics (MD) and quantum-chemical modeling. The experimental spectra were unambiguously assigned to the quadruplex DNA arrangement, and several IR and VCD bands related to this structural motif were determined. Involvement of MD in the modeling was essential for realistic simulation of the spectra. The VCD signal was found to be more sensitive to dynamical structural variations than the IR signal. The combination of the spectroscopic techniques with multiscale simulations provides extended information about nucleic acid conformations and their dynamics.
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Affiliation(s)
- Valery Andrushchenko
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
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Cang X, Šponer J, Cheatham TE. Insight into G-DNA structural polymorphism and folding from sequence and loop connectivity through free energy analysis. J Am Chem Soc 2011; 133:14270-9. [PMID: 21761922 PMCID: PMC3168932 DOI: 10.1021/ja107805r] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
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The lengths of G-tracts and their connecting loop sequences determine G-quadruplex folding and stability. Complete understanding of the sequence–structure relationships remains elusive. Here, single-loop G-quadruplexes were investigated using explicit solvent molecular dynamics (MD) simulations to characterize the effect of loop length, loop sequence, and G-tract length on the folding topologies and stability of G-quadruplexes. Eight loop types, including different variants of lateral, diagonal, and propeller loops, and six different loop sequences [d0 (i.e., no intervening residues in the loop), dT, dT2, dT3, dTTA, and dT4] were considered through MD simulation and free energy analysis. In most cases the free energetic estimates agree well with the experimental observations. The work also provides new insight into G-quadruplex folding and stability. This includes reporting the observed instability of the left propeller loop, which extends the rules for G-quadruplex folding. We also suggest a plausible explanation why human telomere sequences predominantly form hybrid-I and hybrid-II type structures in K+ solution. Overall, our calculation results indicate that short loops generally are less stable than longer loops, and we hypothesize that the extreme stability of sequences with very short loops could possibly derive from the formation of parallel multimers. The results suggest that free energy differences, estimated from MD and free energy analysis with current force fields and simulation protocols, are able to complement experiment and to help dissect and explain loop sequence, loop length, and G-tract length and orientation influences on G-quadruplex structure.
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Affiliation(s)
- Xiaohui Cang
- Department of Medicinal Chemistry, College of Pharmacy, Skaggs Hall 201, University of Utah, Salt Lake City, Utah 84112, USA
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Singh V, Benz A, Hartig JS. G Quadruplexes Stabilised by 8-Oxo-2′-deoxyguanosine. Chemistry 2011; 17:10838-43. [DOI: 10.1002/chem.201100284] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 06/16/2011] [Indexed: 01/19/2023]
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Cang X, Šponer J, Cheatham TE. Explaining the varied glycosidic conformational, G-tract length and sequence preferences for anti-parallel G-quadruplexes. Nucleic Acids Res 2011; 39:4499-512. [PMID: 21296760 PMCID: PMC3105399 DOI: 10.1093/nar/gkr031] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Revised: 01/12/2011] [Accepted: 01/13/2011] [Indexed: 01/08/2023] Open
Abstract
Guanine-rich DNA sequences tend to form four-stranded G-quadruplex structures. Characteristic glycosidic conformational patterns along the G-strands, such as the 5'-syn-anti-syn-anti pattern observed with the Oxytricha nova telomeric G-quadruplexes, have been well documented. However, an explanation for these featured glycosidic patterns has not emerged. This work presents MD simulation and free energetic analyses for simplified two-quartet [d(GG)](4) models and suggests that the four base pair step patterns show quite different relative stabilities: syn-anti > anti-anti > anti-syn > syn-syn. This suggests the following rule: when folding, anti-parallel G-quadruplexes tend to maximize the number of syn-anti steps and avoid the unfavorable anti-syn and syn-syn steps. This rule is consistent with most of the anti-parallel G-quadruplex structures in the Protein Databank (PDB). Structural polymorphisms of G-quadruplexes relate to these glycosidic conformational patterns and the lengths of the G-tracts. The folding topologies of G2- and G4-tracts are not very polymorphic because each strand tends to populate the stable syn-anti repeat. G3-tracts, on the other hand, cannot present this repeating pattern on each G-tract. This leads to smaller energy differences between different geometries and helps explain the extreme structural polymorphism of the human telomeric G-quadruplexes.
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Affiliation(s)
- Xiaohui Cang
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, Utah, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, Brno, Czech Republic and Department of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, University of Utah, Salt Lake City, Utah
| | - Jiří Šponer
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, Utah, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, Brno, Czech Republic and Department of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, University of Utah, Salt Lake City, Utah
| | - Thomas E. Cheatham
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, Utah, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, Brno, Czech Republic and Department of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, University of Utah, Salt Lake City, Utah
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Ranjan N, Andreasen KF, Kumar S, Hyde-Volpe D, Arya DP. Aminoglycoside binding to Oxytricha nova telomeric DNA. Biochemistry 2010; 49:9891-903. [PMID: 20886815 DOI: 10.1021/bi101517e] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Telomeric DNA sequences have been at the center stage of drug design for cancer treatment in recent years. The ability of these DNA structures to form four-stranded nucleic acid structures, called G-quadruplexes, has been perceived as target for inhibiting telomerase activity vital for the longevity of cancer cells. Being highly diverse in structural forms, these G-quadruplexes are subjects of detailed studies of ligand-DNA interactions of different classes, which will pave the way for logical design of more potent ligands in future. The binding of aminoglycosides was investigated with Oxytricha nova quadruplex forming DNA sequence (GGGGTTTTGGGG)(2). Isothermal titration calorimetry (ITC) determined ligand to quadruplex binding ratio shows 1:1 neomycin:quadruplex binding with association constants (K(a)) ∼ 10(5) M(-1) while paromomycin was found to have a 2-fold weaker affinity than neomycin. The CD titration experiments with neomycin resulted in minimal changes in the CD signal. FID assays, performed to determine the minimum concentration required to displace half of the fluorescent probe bound, showed neomycin as the best of the all aminoglycosides studied for quadruplex binding. Initial NMR footprint suggests that ligand-DNA interactions occur in the wide groove of the quadruplex. Computational docking studies also indicate that aminoglycosides bind in the wide groove of the quadruplex.
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Affiliation(s)
- Nihar Ranjan
- Laboratories of Medicinal Chemistry, Clemson University, Clemson, South Carolina 29634, United States
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45
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Dutta K, Fujimoto T, Inoue M, Miyoshi D, Sugimoto N. Development of new functional nanostructures consisting of both DNA duplex and quadruplex. Chem Commun (Camb) 2010; 46:7772-4. [PMID: 20820501 DOI: 10.1039/c0cc00710b] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The sequence specificity of a duplex and the cation dependent self-assembly of a G-quadruplex were combined to design rationally DNA G-quadruplex arrays connected by duplexes.
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Affiliation(s)
- Kakoli Dutta
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
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46
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Holm AIS, Nielsen LM, Hoffmann SV, Nielsen SB. Vacuum-ultraviolet circular dichroism spectroscopy of DNA: a valuable tool to elucidate topology and electronic coupling in DNA. Phys Chem Chem Phys 2010; 12:9581-96. [PMID: 20607185 DOI: 10.1039/c003446k] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Circular dichroism (CD) is a powerful technique to obtain information on electronic transitions and has been used extensively for studies on DNA. Most experiments are done in the UV region but new information is often revealed from extending the wavelength region down into the vacuum ultraviolet (VUV) region. Such experiments are most easily carried out with synchrotron radiation (SR) light sources that provide large photon fluxes. Here we provide a summary of the SRCD data taken on different DNA strands with emphasis on results from our own laboratory within the last five years.(1-3) Signal intensities in the VUV are often significantly larger than those in the UV, and the electronic coupling between bases may increase with excitation energy. CD spectroscopy is particularly useful for investigating the extent of electronic coupling within a strand, i.e., the degree of delocalisation of the excited-state electronic wavefunction. The spatial extent of the wavefunction may be limited to just one base or it extends over two or more bases in a stack or between bases on different strands.(4,5) The actual character of the electronically excited state is linked to base composition and sequence as well as DNA folding motif (A-, B-, Z-DNA, triplexes, quadruplexes, etc.). The latter depends on experimental conditions such as solution acidity, temperature, ionic strength, and solvent.
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Affiliation(s)
- Anne Ivalu Sander Holm
- Department of Physics, Stockholm University, AlbaNova University Center, S-10691 Stockholm, Sweden.
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47
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Toward a full structural characterization of G-quadruplex DNA in aqueous solution: Molecular dynamics simulations of four G-quadruplex molecules. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.theochem.2010.04.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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48
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Holm AIS, Kohler B, Hoffmann SV, Brøndsted Nielsen S. Synchrotron radiation circular dichroism of various G-quadruplex structures. Biopolymers 2010; 93:429-33. [PMID: 19937757 DOI: 10.1002/bip.21354] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Here we report synchrotron radiation circular dichroism spectra of various G-quadruplexes from 179 to 350 nm, and a number of bands in the vacuum ultraviolet (VUV) are reported for the first time. For a tetramolecular parallel structure, the strongest band in the spectrum is a negative band in the VUV at 182 nm; for a bimolecular antiparallel structure with diagonal loops, a new strong positive band is found at 190 nm; for a bimolecular parallel structure with edgewise loops, a strong positive band at 189 nm is observed; and for a self-folded chair-type structure, the strongest band in the spectrum is a positive band at 187 nm. For the tetramolecular parallel structure, the CD signals at all wavelengths are dominated by contributions from quartets of G bases, and the signal strength is approximately proportional to the number of quartets. Our experiments on well-characterized G-quadruplex structures lead us to question past attributions of CD signals to helix handedness and G quartet polarity. Although differences can be observed in the VUV region for the various quadruplex types, there do not appear to be clear-cut spectral features that can be used to identify specific topological features. It is suggested that this is because a dominant positive band in the VUV seen near 190 nm in all quadruplex structures is due to intrastrand guanine-guanine base stacking. However, our spectra can serve as reference spectra for the G-quadruplex structures investigated and, not least, to benchmark theoretical calculations and empirical models.
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Affiliation(s)
- Anne I S Holm
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark.
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Haider S, Neidle S. Molecular modeling and simulation of G-quadruplexes and quadruplex-ligand complexes. Methods Mol Biol 2010; 608:17-37. [PMID: 20012413 DOI: 10.1007/978-1-59745-363-9_2] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Methods for the molecular modeling and simulation of G-quadruplex structures and their drug/ligand complexes are discussed, and a range of protocols is presented for undertaking a variety of tasks including model-building, ligand docking, dynamics simulation, continuum solvent modeling, energetic calculations, principal component analysis, and quantum chemical computations. The scope and limitations of these approaches are discussed.
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Affiliation(s)
- Shozeb Haider
- The Cancer Research UK Biomolecular Structure Group, The School of Pharmacy, University of London, London, UK
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50
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Abstract
G-quartets are square planar arrangements of four guanine bases, which can form extraordinarily stable stacks when present in nucleic acid sequences. Such G-quadruplex structures were long regarded as an in vitro phenomenon, but the widespread presence of suitable sequences in genomes and the identification of proteins that stabilize, modify, or resolve these nucleic acid structures have provided circumstantial evidence for their physiological relevance. The therapeutic potential of small molecules that can stabilize or disrupt G-quadruplex structures has invigorated the field in recent years. Here we review some of the key observations that support biological functions for G-quadruplex DNA as well as the techniques and tools that have enabled researchers to probe these structures and their interactions with proteins and small molecules.
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Affiliation(s)
- Tracy M Bryan
- Children's Medical Research Institute and the University of Sydney, Sydney, Australia
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