1
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Zhao L, Cheng L, Yang Y, Wang P, Tian P, Yang T, Nian H, Cao L. Biomimetic Hydrogen-Bonded G ⋅ C ⋅ G ⋅ C Quadruplex within a Tetraphenylethene-Based Octacationic Spirobicycle in Water. Angew Chem Int Ed Engl 2024; 63:e202405150. [PMID: 38591857 DOI: 10.1002/anie.202405150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/01/2024] [Accepted: 04/09/2024] [Indexed: 04/10/2024]
Abstract
In biological systems, nucleotide quadruplexes (such as G-quadruplexes) in DNA and RNA that are held together by multiple hydrogen bonds play a crucial functional role. The biomimetic formation of these hydrogen-bonded quadruplexes captured by artificial systems in water poses a significant challenge but can offer valuable insights into these complex functional structures. Herein, we report the formation of biomimetic hydrogen-bonded G ⋅ C ⋅ G ⋅ C quadruplex captured by a tetraphenylethene (TPE) based octacationic spirobicycle (1). The spirobicyclic compound possesses a three-dimensional (3D) crossing dual-cavity structure, which enables the encapsulation of four d(GpC) dinucleotide molecules, thereby realizing 1 : 4 host-guest complexation in water. The X-ray structure reveals that four d(GpC) molecules further form a two-layer G ⋅ C ⋅ G ⋅ C quadruplex with Watson-Crick hydrogen bonds, which are stabilized within the dual hydrophobic cavities of 1 through the cooperative non-covalent interactions of hydrogen bonds, CH⋅⋅⋅π interactions, and hydrophobic effect. Due to the dynamically-rotational propeller chirality of TPE units, 1 with adaptive chirality can further serve as a chiroptical sensor to exhibit opposite Cotton effects with mirror-image CD spectra for the pH-dependent hydrogen-bonded assemblies of d(GpC) including the Watson-Crick G ⋅ C ⋅ G ⋅ C (pH 9.22) and Hoogsteen G ⋅ C+ ⋅ G ⋅ C+ (pH 5.74) quartets through the host-guest chirality transfer in water.
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Affiliation(s)
- Lingyu Zhao
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
| | - Lin Cheng
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
| | - Yanxia Yang
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
| | - Pingxia Wang
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
| | - Ping Tian
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
| | - Ting Yang
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
| | - Hao Nian
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
| | - Liping Cao
- College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China)
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2
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Wu H, Zhang T, Qin Y, Xia X, Bai T, Gu H, Wei B. Expanding DNA Origami Design Freedom with De Novo Synthesized Scaffolds. J Am Chem Soc 2024; 146:16076-16084. [PMID: 38803270 DOI: 10.1021/jacs.4c03148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
The construction of DNA origami nanostructures is heavily dependent on the folding of the scaffold strand, which is typically a single-stranded DNA genome extracted from a bacteriophage (M13). Custom scaffolds can be prepared in a number of methods, but they are not widely accessible to a broad user base in the DNA nanotechnology community. Here, we explored new design and construction possibilities with custom scaffolds prepared in our cost- and time-efficient production pipeline. According to the pipeline, we de novo produced a variety of scaffolds of specified local and global sequence characteristics and consequent origami constructs of modular arrangement in morphologies and functionalities. Taking advantage of this strategy of template-free scaffold production, we also designed and produced three-letter-coded scaffolds that can fold into designated morphologies rapidly at room temperature. The expanded design and construction freedom immediately brings in many new research opportunities and invites many more on the horizon.
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Affiliation(s)
- Hongrui Wu
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
| | - Tianqing Zhang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
| | - Yan Qin
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
| | - Xinwei Xia
- Department of Chemical Biology, School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai 201108 ,China
| | - Tanxi Bai
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
| | - Hongzhou Gu
- Department of Chemical Biology, School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai 201108 ,China
| | - Bryan Wei
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
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3
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Gajarsky M, Stadlbauer P, Sponer J, Cucchiarini A, Dobrovolna M, Brazda V, Mergny JL, Trantirek L, Lenarcic Zivkovic M. DNA Quadruplex Structure with a Unique Cation Dependency. Angew Chem Int Ed Engl 2024; 63:e202313226. [PMID: 38143239 DOI: 10.1002/anie.202313226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 12/11/2023] [Accepted: 12/22/2023] [Indexed: 12/26/2023]
Abstract
DNA quadruplex structures provide an additional layer of regulatory control in genome maintenance and gene expression and are widely used in nanotechnology. We report the discovery of an unprecedented tetrastranded structure formed from a native G-rich DNA sequence originating from the telomeric region of Caenorhabditis elegans. The structure is defined by multiple properties that distinguish it from all other known DNA quadruplexes. Most notably, the formation of a stable so-called KNa-quadruplex (KNaQ) requires concurrent coordination of K+ and Na+ ions at two distinct binding sites. This structure provides novel insight into G-rich DNA folding under ionic conditions relevant to eukaryotic cell physiology and the structural evolution of telomeric DNA. It highlights the differences between the structural organization of human and nematode telomeric DNA, which should be considered when using C. elegans as a model in telomere biology, particularly in drug screening applications. Additionally, the absence/presence of KNaQ motifs in the host/parasite introduces an intriguing possibility of exploiting the KNaQ fold as a plausible antiparasitic drug target. The structure's unique shape and ion dependency and the possibility of controlling its folding by using low-molecular-weight ligands can be used for the design or discovery of novel recognition DNA elements and sensors.
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Affiliation(s)
- Martin Gajarsky
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 753/5, 62500, Brno, Czech Republic
- Current address: Center for Molecular Medicine Cologne, University of Cologne, 50931, Cologne, Germany
| | - Petr Stadlbauer
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
| | - Jiri Sponer
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
| | - Anne Cucchiarini
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 753/5, 62500, Brno, Czech Republic
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91120, Palaiseau, France
| | - Michaela Dobrovolna
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
- Faculty of Chemistry, Brno University of Technology, Purkynova 464, 61200, Brno, Czech Republic
| | - Vaclav Brazda
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
- Faculty of Chemistry, Brno University of Technology, Purkynova 464, 61200, Brno, Czech Republic
| | - Jean-Louis Mergny
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91120, Palaiseau, France
| | - Lukas Trantirek
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 753/5, 62500, Brno, Czech Republic
| | - Martina Lenarcic Zivkovic
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 753/5, 62500, Brno, Czech Republic
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
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4
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Luo Y, Živković ML, Wang J, Ryneš J, Foldynová-Trantírková S, Trantírek L, Verga D, Mergny JL. A sodium/potassium switch for G4-prone G/C-rich sequences. Nucleic Acids Res 2024; 52:448-461. [PMID: 37986223 PMCID: PMC10783510 DOI: 10.1093/nar/gkad1073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 10/19/2023] [Accepted: 11/03/2023] [Indexed: 11/22/2023] Open
Abstract
Metal ions are essential components for the survival of living organisms. For most species, intracellular and extracellular ionic conditions differ significantly. As G-quadruplexes (G4s) are ion-dependent structures, changes in the [Na+]/[K+] ratio may affect the folding of genomic G4s. More than 11000 putative G4 sequences in the human genome (hg19) contain at least two runs of three continuous cytosines, and these mixed G/C-rich sequences may form a quadruplex or a competing hairpin structure based on G-C base pairing. In this study, we examine how the [Na+]/[K+] ratio influences the structures of G/C-rich sequences. The natural G4 structure with a 9-nt long central loop, CEBwt, was chosen as a model sequence, and the loop bases were gradually replaced by cytosines. The series of CEB mutations revealed that the presence of cytosines in G4 loops does not prevent G4 folding or decrease G4 stability but increases the probability of forming a competing structure, either a hairpin or an intermolecular duplex. Slow conversion to the quadruplex in vitro (in a potassium-rich buffer) and cells was demonstrated by NMR. 'Shape-shifting' sequences may respond to [Na+]/[K+] changes with delayed kinetics.
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Affiliation(s)
- Yu Luo
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91128 Palaiseau, France
- CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France
| | - Martina Lenarčič Živković
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
- Slovenian NMR Centre, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia
| | - Jiawei Wang
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91128 Palaiseau, France
| | - Jan Ryneš
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | | | - Lukáš Trantírek
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | - Daniela Verga
- CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, F-91405 Orsay, France
| | - Jean-Louis Mergny
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91128 Palaiseau, France
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5
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Zalar M, Wang B, Plavec J, Šket P. Insight into Tetramolecular DNA G-Quadruplexes Associated with ALS and FTLD: Cation Interactions and Formation of Higher-Ordered Structure. Int J Mol Sci 2023; 24:13437. [PMID: 37686239 PMCID: PMC10487854 DOI: 10.3390/ijms241713437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/24/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
The G4C2 hexanucleotide repeat expansion in the c9orf72 gene is a major genetic cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), with the formation of G-quadruplexes directly linked to the development of these diseases. Cations play a crucial role in the formation and structure of G-quadruplexes. In this study, we investigated the impact of biologically relevant potassium ions on G-quadruplex structures and utilized 15N-labeled ammonium cations as a substitute for K+ ions to gain further insights into cation binding and exchange dynamics. Through nuclear magnetic resonance spectroscopy and molecular dynamics simulations, we demonstrate that the single d(G4C2) repeat, in the presence of 15NH4+ ions, adopts a tetramolecular G-quadruplex with an all-syn quartet at the 5'-end. The movement of 15NH4+ ions through the central channel of the G-quadruplex, as well as to the bulk solution, is governed by the vacant cation binding site, in addition to the all-syn quartet at the 5'-end. Furthermore, the addition of K+ ions to G-quadruplexes folded in the presence of 15NH4+ ions induces stacking of G-quadruplexes via their 5'-end G-quartets, leading to the formation of stable higher-ordered species.
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Affiliation(s)
- Matja Zalar
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
| | - Baifan Wang
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
- EN-FIST Center of Excellence, Trg OF 13, SI-1000 Ljubljana, Slovenia
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Primož Šket
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
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6
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Trizna L, Osif B, Víglaský V. G-QINDER Tool: Bioinformatically Predicted Formation of Different Four-Stranded DNA Motifs from (GT) n and (GA) n Repeats. Int J Mol Sci 2023; 24:ijms24087565. [PMID: 37108727 DOI: 10.3390/ijms24087565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/10/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
The recently introduced semi-orthogonal system of nucleic acid imaging offers a greatly improved method of identifying DNA sequences that are capable of adopting noncanonical structures. This paper uses our newly developed G-QINDER tool to identify specific repeat sequences that adopt unique structural motifs in DNA: TG and AG repeats. The structures were found to adopt a left-handed G-quadruplex form under extreme crowding conditions and a unique tetrahelical motif under certain other conditions. The tetrahelical structure likely consists of stacked AGAG-tetrads but, unlike G-quadruplexes, their stability does not appear to be dependent on the type of monovalent cation present. The occurrence of TG and AG repeats in genomes is not rare, and they are also found frequently in the regulatory regions of nucleic acids, so it is reasonable to assume that putative structural motifs, like other noncanonical forms, could play an important regulatory role in cells. This hypothesis is supported by the structural stability of the AGAG motif; its unfolding can occur even at physiological temperatures since the melting temperature is primarily dependent on the number of AG repeats in the sequence.
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Affiliation(s)
- Lukáš Trizna
- Department of Biochemistry, Institute of Chemistry, Faculty of Sciences, Pavol Jozef Šafárik University, 04001 Košice, Slovakia
| | - Branislav Osif
- Department of Biochemistry, Institute of Chemistry, Faculty of Sciences, Pavol Jozef Šafárik University, 04001 Košice, Slovakia
| | - Viktor Víglaský
- Department of Biochemistry, Institute of Chemistry, Faculty of Sciences, Pavol Jozef Šafárik University, 04001 Košice, Slovakia
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7
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Ye M, Chen EV, Pfeil SH, Martin KN, Atrafi T, Yun S, Martinez Z, Yatsunyk LA. Homopurine guanine-rich sequences in complex with N-methyl mesoporphyrin IX form parallel G-quadruplex dimers and display a unique symmetry tetrad. Bioorg Med Chem 2023; 77:117112. [PMID: 36508994 PMCID: PMC9812923 DOI: 10.1016/j.bmc.2022.117112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/24/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022]
Abstract
DNA can fold into G-quadruplexes (GQs), non-canonical secondary structures formed by π-π stacking of G-tetrads. GQs are important in many biological processes, which makes them promising therapeutic targets. We identified a 42-nucleotide long, purine-only G-rich sequence from human genome, which contains eight G-stretches connected by A and AAAA loops. We divided this sequence into five unique segments, four guanine stretches each, named GA1-5. In order to investigate the role of adenines in GQ structure formation, we performed biophysical and X-ray crystallographic studies of GA1-5 and their complexes with a highly selective GQ ligand, N-methyl mesoporphyrin IX (NMM). Our data indicate that all variants form parallel GQs whose stability depends on the number of flexible AAAA loops. GA1-3 bind NMM with 1:1 stoichiometry. The Ka for GA1 and GA3 is modest, ∼0.3 μM -1, and that for GA2 is significantly higher, ∼1.2 μM -1. NMM stabilizes GA1-3 by 14.6, 13.1, and 7.0 °C, respectively, at 2 equivalents. We determined X-ray crystal structures of GA1-NMM (1.98 Å resolution) and GA3-NMM (2.01 Å). The structures confirm the parallel topology of GQs with all adenines forming loops and display NMM binding at the 3' G-tetrad. Both complexes dimerize through the 5' interface. We observe two novel structural features: 1) a 'symmetry tetrad' at the dimer interface, which is formed by two guanines from each GQ monomer and 2) a NMM dimer in GA1-NMM. Our structural work confirms great flexibility of adenines as structural elements in GQ formation and contributes greatly to our understanding of the structural diversity of GQs and their modes of interaction with small molecule ligands.
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Affiliation(s)
- Ming Ye
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, United States
| | - Erin V Chen
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, United States
| | - Shawn H Pfeil
- Department of Physics, West Chester University, West Chester, PA 19383, United States
| | - Kailey N Martin
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, United States
| | - Tamanaa Atrafi
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, United States
| | - Sara Yun
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, United States
| | - Zahara Martinez
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, United States
| | - Liliya A Yatsunyk
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, United States.
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8
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Oblak D, Hadži S, Podlipnik Č, Lah J. Binding-Induced Diversity of a Human Telomeric G-Quadruplex Stability Phase Space. Pharmaceuticals (Basel) 2022; 15:ph15091150. [PMID: 36145371 PMCID: PMC9501445 DOI: 10.3390/ph15091150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/06/2022] [Accepted: 09/11/2022] [Indexed: 11/25/2022] Open
Abstract
The structural polymorphism of G-quadruplex nucleic acids is an important factor in their recognition by proteins and small-molecule ligands. However, it is not clear why the binding of several ligands alters G-quadruplex topology. We addressed this question by following the (un)folding and binding of the human telomeric fragment 5′-(GGGTTA)3GGGT-3′ (22GT) by calorimetry (DSC, ITC) and spectroscopy (CD). A thermodynamic analysis of the obtained data led to a detailed description of the topological phase space of stability (phase diagram) of 22GT and shows how it changes in the presence of a specific bisquinolinium ligand (360A). Various 1:1 and 2:1 ligand–quadruplex complexes were observed. With increasing temperature, the 1:1 complexes transformed into 2:1 complexes, which is attributed to the preferential binding of the ligand to the folding intermediates. Overall, the dissection of the thermodynamic parameters in combination with molecular modelling clarified the driving forces of the topological quadruplex transformations in a wide range of ligand concentrations and temperatures.
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9
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Non-G Base Tetrads. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27165287. [PMID: 36014524 PMCID: PMC9414646 DOI: 10.3390/molecules27165287] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/03/2022] [Accepted: 08/11/2022] [Indexed: 11/17/2022]
Abstract
Tetrads (or quartets) are arrangements of four nucleobases commonly involved in the stability of four-stranded nucleic acids structures. Four-stranded or quadruplex structures have attracted enormous attention in the last few years, being the most extensively studied guanine quadruplex (G-quadruplex). Consequently, the G-tetrad is the most common and well-known tetrad. However, this is not the only possible arrangement of four nucleobases. A number of tetrads formed by the different nucleobases have been observed in experimental structures. In most cases, these tetrads occur in the context of G-quadruplex structures, either inserted between G-quartets, or as capping elements at the sides of the G-quadruplex core. In other cases, however, non-G tetrads are found in more unusual four stranded structures, such as i-motifs, or different types of peculiar fold-back structures. In this report, we review the diversity of these non-canonical tetrads, and the structural context in which they have been found.
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10
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Hertel S, Spinney RE, Xu SY, Ouldridge TE, Morris RG, Lee LK. The stability and number of nucleating interactions determine DNA hybridization rates in the absence of secondary structure. Nucleic Acids Res 2022; 50:7829-7841. [PMID: 35880577 PMCID: PMC9371923 DOI: 10.1093/nar/gkac590] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 06/23/2022] [Accepted: 07/25/2022] [Indexed: 11/12/2022] Open
Abstract
The kinetics of DNA hybridization are fundamental to biological processes and DNA-based technologies. However, the precise physical mechanisms that determine why different DNA sequences hybridize at different rates are not well understood. Secondary structure is one predictable factor that influences hybridization rates but is not sufficient on its own to fully explain the observed sequence-dependent variance. In this context, we measured hybridization rates of 43 different DNA sequences that are not predicted to form secondary structure and present a parsimonious physically justified model to quantify our observations. Accounting only for the combinatorics of complementary nucleating interactions and their sequence-dependent stability, the model achieves good correlation with experiment with only two free parameters. Our results indicate that greater repetition of Watson-Crick pairs increases the number of initial states able to proceed to full hybridization, with the stability of those pairings dictating the likelihood of such progression, thus providing new insight into the physical factors underpinning DNA hybridization rates.
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Affiliation(s)
- Sophie Hertel
- EMBL Australia Node for Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney 2052, Australia
| | - Richard E Spinney
- EMBL Australia Node for Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney 2052, Australia.,School of Physics, University of New South Wales, Sydney 2052, Australia
| | - Stephanie Y Xu
- EMBL Australia Node for Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney 2052, Australia
| | - Thomas E Ouldridge
- Department of Bioengineering and Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK
| | - Richard G Morris
- EMBL Australia Node for Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney 2052, Australia.,School of Physics, University of New South Wales, Sydney 2052, Australia
| | - Lawrence K Lee
- EMBL Australia Node for Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney 2052, Australia.,ARC Centre of Excellence in Synthetic Biology, University of New South Wales, Sydney, Australia
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11
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Ruggiero E, Lavezzo E, Grazioli M, Zanin I, Marušič M, Plavec J, Richter SN, Toppo S. Human Virus Genomes Are Enriched in Conserved Adenine/Thymine/Uracil Multiple Tracts That Pause Polymerase Progression. Front Microbiol 2022; 13:915069. [PMID: 35722311 PMCID: PMC9198555 DOI: 10.3389/fmicb.2022.915069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
The DNA secondary structures that deviate from the classic Watson and Crick base pairing are increasingly being reported to form transiently in the cell and regulate specific cellular mechanisms. Human viruses are cell parasites that have evolved mechanisms shared with the host cell to support their own replication and spreading. Contrary to human host cells, viruses display a diverse array of nucleic acid types, which include DNA or RNA in single-stranded or double-stranded conformations. This heterogeneity improves the possible occurrence of non-canonical nucleic acid structures. We have previously shown that human virus genomes are enriched in G-rich sequences that fold in four-stranded nucleic acid secondary structures, the G-quadruplexes.Here, by extensive bioinformatics analysis on all available genomes, we showed that human viruses are enriched in highly conserved multiple A (and T or U) tracts, with such an array that they could in principle form quadruplex structures. By circular dichroism, NMR, and Taq polymerase stop assays, we proved that, while A/T/U-quadruplexes do not form, these tracts still display biological significance, as they invariably trigger polymerase pausing within two bases from the A/T/U tract. “A” bases display the strongest effect. Most of the identified A-tracts are in the coding strand, both at the DNA and RNA levels, suggesting their possible relevance during viral translation. This study expands on the presence and mechanism of nucleic acid secondary structures in human viruses and provides a new direction for antiviral research.
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Affiliation(s)
| | - Enrico Lavezzo
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Marco Grazioli
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Irene Zanin
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Maja Marušič
- Slovenian NMR Centre, National Institute of Chemistry, Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Ljubljana, Slovenia
| | - Sara N Richter
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, University of Padua, Padua, Italy.,CRIBI Biotechnology Center, University of Padua, Padua, Italy
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12
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Shokri E, Hosseini M, Boldaji MN, Shahsavar K, amiri-Sadeghan A, Nasiri N, Bahmani A, Ganjali MR, Saboury AA. A novel DNA/hemin complex with enzyme-like activity selected from a hairpin DNAs library at zero H2O2 concentration. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2022.112156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Grün JT, Schwalbe H. Folding dynamics of polymorphic G-quadruplex structures. Biopolymers 2021; 113:e23477. [PMID: 34664713 DOI: 10.1002/bip.23477] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 12/14/2022]
Abstract
G-quadruplexes (G4), found in numerous places within the human genome, are involved in essential processes of cell regulation. Chromosomal DNA G4s are involved for example, in replication and transcription as first steps of gene expression. Hence, they influence a plethora of downstream processes. G4s possess an intricate structure that differs from canonical B-form DNA. Identical DNA G4 sequences can adopt multiple long-lived conformations, a phenomenon known as G4 polymorphism. A detailed understanding of the molecular mechanisms that drive G4 folding is essential to understand their ambivalent regulatory roles. Disentangling the inherent dynamic and polymorphic nature of G4 structures thus is key to unravel their biological functions and make them amenable as molecular targets in novel therapeutic approaches. We here review recent experimental approaches to monitor G4 folding and discuss structural aspects for possible folding pathways. Substantial progress in the understanding of G4 folding within the recent years now allows drawing comprehensive models of the complex folding energy landscape of G4s that we herein evaluate based on computational and experimental evidence.
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Affiliation(s)
- J Tassilo Grün
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology, Johann Wolfgang Goethe-University, Frankfurt/M, Germany.,Center for Biomolecular Magnetic Resonance (BMRZ), Johann Wolfgang Goethe-University Frankfurt, Frankfurt/M, Germany
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14
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Liu L, Wang K, Liu W, Zeng Y, Hou M, Yang J, Mao Z. Spatial Matching Selectivity and Solution Structure of Organic–Metal Hybrid to Quadruplex–Duplex Hybrid. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Liu‐Yi Liu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry, State Key Laboratory of Oncology in South China Sun Yat-Sen University Guangzhou 510275 P. R. China
| | - Kang‐Nan Wang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry, State Key Laboratory of Oncology in South China Sun Yat-Sen University Guangzhou 510275 P. R. China
| | - Wenting Liu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry, State Key Laboratory of Oncology in South China Sun Yat-Sen University Guangzhou 510275 P. R. China
| | - You‐Liang Zeng
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry, State Key Laboratory of Oncology in South China Sun Yat-Sen University Guangzhou 510275 P. R. China
| | - Ming‐Xuan Hou
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry, State Key Laboratory of Oncology in South China Sun Yat-Sen University Guangzhou 510275 P. R. China
| | - Jing Yang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry, State Key Laboratory of Oncology in South China Sun Yat-Sen University Guangzhou 510275 P. R. China
| | - Zong‐Wan Mao
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry, State Key Laboratory of Oncology in South China Sun Yat-Sen University Guangzhou 510275 P. R. China
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15
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Serrano-Chacón I, Mir B, Escaja N, González C. Structure of i-Motif/Duplex Junctions at Neutral pH. J Am Chem Soc 2021; 143:12919-12923. [PMID: 34370473 PMCID: PMC8397320 DOI: 10.1021/jacs.1c04679] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We report here the three-dimensional structure of an i-motif/duplex junction, determined by NMR methods at neutral pH. By including a minor groove tetrad at one side of the C:C+ stack of a monomeric i-motif, and a stem/loop hairpin at the other side, we have designed stable DNA constructs in which i-DNA and B-DNA regions coexist in a wide range of experimental conditions. This study demonstrates that i- and B-DNA are structurally compatible, giving rise to a distinctive fold with peculiar groove shapes. The effect of different residues at the i-motif/duplex interface has been explored. We also show that these constructs can be adapted to sequences of biological relevance, like that found in the promoter region of the KRAS oncogene.
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Affiliation(s)
| | - Bartomeu Mir
- Inorganic and Organic Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Núria Escaja
- Inorganic and Organic Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain.,BIOESTRAN associated unit UB-CSIC, 08028 Barcelona, Spain
| | - Carlos González
- Instituto de Química Física 'Rocasolano', CSIC, Serrano 119, 28006 Madrid, Spain.,BIOESTRAN associated unit UB-CSIC, 08028 Barcelona, Spain
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16
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Liu LY, Wang KN, Liu W, Zeng YL, Hou MX, Yang J, Mao ZW. Spatial Matching Selectivity and Solution Structure of Organic-Metal Hybrid to Quadruplex-Duplex Hybrid. Angew Chem Int Ed Engl 2021; 60:20833-20839. [PMID: 34288320 DOI: 10.1002/anie.202106256] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 06/27/2021] [Indexed: 12/16/2022]
Abstract
The sequence-dependent DNA secondary structures possess structure polymorphism. To date, studies on regulated ligands mainly focus on individual DNA secondary topologies, while lack focus on quadruplex-duplex hybrids (QDHs). Here, we design an organic-metal hybrid ligand L1 Pt(dien), which matches and selectively binds one type of QDHs with lateral duplex stem-loop (QLDH) with high affinity, while shows poor affinity for other QDHs and individual G4 or duplex DNA. The solution structure of QLDH MYT1L-L1 Pt(dien) complex was determined by NMR. The structure reveals that L1 Pt(dien) presents a chair-type conformation, whose large aromatic "chair surface" intercalates into the G-quadruplex-duplex interface via π-π stacking and "backrest" platinum unit interacts with duplex region through hydrogen bonding and electrostatic interactions, showing a highly matched lock-key binding mode. Our work provided guidance for spatial matching design of selectively targeting ligands to QDH structures.
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Affiliation(s)
- Liu-Yi Liu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, State Key Laboratory of Oncology in South China, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Kang-Nan Wang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, State Key Laboratory of Oncology in South China, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Wenting Liu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, State Key Laboratory of Oncology in South China, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - You-Liang Zeng
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, State Key Laboratory of Oncology in South China, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Ming-Xuan Hou
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, State Key Laboratory of Oncology in South China, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Jing Yang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, State Key Laboratory of Oncology in South China, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Zong-Wan Mao
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, State Key Laboratory of Oncology in South China, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
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17
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Tomaszewska M, Szabat M, Zielińska K, Kierzek R. Identification and Structural Aspects of G-Quadruplex-Forming Sequences from the Influenza A Virus Genome. Int J Mol Sci 2021; 22:6031. [PMID: 34199658 PMCID: PMC8199785 DOI: 10.3390/ijms22116031] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/26/2021] [Accepted: 05/31/2021] [Indexed: 12/19/2022] Open
Abstract
Influenza A virus (IAV) causes seasonal epidemics and sporadic pandemics, therefore is an important research subject for scientists around the world. Despite the high variability of its genome, the structure of viral RNA (vRNA) possesses features that remain constant between strains and are biologically important for virus replication. Therefore, conserved structural motifs of vRNA can represent a novel therapeutic target. Here, we focused on the presence of G-rich sequences within the influenza A/California/07/2009(H1N1) genome and their ability to form RNA G-quadruplex structures (G4s). We identified 12 potential quadruplex-forming sequences (PQS) and determined their conservation among the IAV strains using bioinformatics tools. Then we examined the propensity of PQS to fold into G4s by various biophysical methods. Our results revealed that six PQS oligomers could form RNA G-quadruplexes. However, three of them were confirmed to adopt G4 structures by all utilized methods. Moreover, we showed that these PQS motifs are present within segments encoding polymerase complex proteins indicating their possible role in the virus biology.
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Affiliation(s)
- Maria Tomaszewska
- Department of Structural Chemistry and Biology of Nucleic Acids, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland;
| | - Marta Szabat
- Department of Structural Chemistry and Biology of Nucleic Acids, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland;
| | - Karolina Zielińska
- Department of Biomolecular NMR, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland;
| | - Ryszard Kierzek
- Department of Structural Chemistry and Biology of Nucleic Acids, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland;
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18
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Grün JT, Blümler A, Burkhart I, Wirmer-Bartoschek J, Heckel A, Schwalbe H. Unraveling the Kinetics of Spare-Tire DNA G-Quadruplex Folding. J Am Chem Soc 2021; 143:6185-6193. [PMID: 33872503 DOI: 10.1021/jacs.1c01089] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The folding of DNA G-quadruplexes (G4) is essential to regulate expression of oncogenes and involves polymorphic long-lived intermediate states. G4 formation requires four G-tracts, but human gene-promoters often contain multiple G-tracts that act as spare-tires. These additional G-tracts are highly conserved and add multiple layers of functional complexity, as they are crucial to maintain G4 function after oxidative damage. Herein, we unravel the folding dynamics of the G4 sequence containing five G-tracts from cMYC, the major proliferation-driving oncogene. We devise a general method to induce folding at constant experimental conditions using a photochemical trapping strategy. Our data dissect the individual kinetics and thermodynamics of the spare-tire mechanism of cMYC-G4.
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Affiliation(s)
- J Tassilo Grün
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Anja Blümler
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Ines Burkhart
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Julia Wirmer-Bartoschek
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Alexander Heckel
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
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19
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Xiang X, Bao Y, Sun L, Zhang Y, Guo X. A stable uncompleted tetramolecular G-quadruplex formed by d(AG nA) under acidic condition. Int J Biol Macromol 2021; 176:66-71. [PMID: 33577823 DOI: 10.1016/j.ijbiomac.2021.02.059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 02/06/2021] [Accepted: 02/07/2021] [Indexed: 01/12/2023]
Abstract
In this work, the effects of terminal adenines on the formation and stability of tetramolecular G-quadruplexes (G4s) have been studied by electrospray ionization mass spectrometry (ESI-MS), UV, CD and NMR spectroscopy. Several evidences suggested that the sequences d(AGnA) (n = 4 or 5) form stable uncompleted tetramolecular G4 at acidic condition which is different from the canonical one in the neutral condition. In addition, hydrolysis of guanine has also been observed in acidic condition that may occur for unpaired strands rather than in complete G4. Thus, a new G4 topology containing incomplete G-quartet is proposed that is very stable and particularly presents in acidic ammonium ions solution. The information presented in this study provides the new insight on the polymorphism of G4s in acidic environment, which may help understand of the special role of adenines on the formation of G4s.
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Affiliation(s)
- Xiaoxuan Xiang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
| | - Ying Bao
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
| | - Likang Sun
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
| | - Yujing Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
| | - Xinhua Guo
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China; Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, College of Life Science, Jilin University, Changchun 130012, China.
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20
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Zuffo M, Gandolfini A, Heddi B, Granzhan A. Harnessing intrinsic fluorescence for typing of secondary structures of DNA. Nucleic Acids Res 2020; 48:e61. [PMID: 32313962 PMCID: PMC7293009 DOI: 10.1093/nar/gkaa257] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/28/2020] [Accepted: 04/03/2020] [Indexed: 12/15/2022] Open
Abstract
High-throughput investigation of structural diversity of nucleic acids is hampered by the lack of suitable label-free methods, combining fast and cheap experimental workflow with high information content. Here, we explore the use of intrinsic fluorescence emitted by nucleic acids for this scope. After a preliminary assessment of suitability of this phenomenon for tracking conformational changes of DNA, we examined steady-state emission spectra of an 89-membered set of oligonucleotides with reported conformation (G-quadruplexes (G4s), i-motifs, single- and double-strands) by means of multivariate analysis. Principal component analysis of emission spectra resulted in successful clustering of oligonucleotides into three corresponding conformational groups, without discrimination between single- and double-stranded structures. Linear discriminant analysis was exploited for the assessment of novel sequences, allowing the evaluation of their G4-forming propensity. Our method does not require any labeling agent or dye, avoiding the related bias, and can be utilized to screen novel sequences of interest in a high-throughput and cost-effective manner. In addition, we observed that left-handed (Z-) G4 structures were systematically more fluorescent than most other G4 structures, almost reaching the quantum yield of 5'-d[(G3T)3G3]-3' (G3T, the most fluorescent G4 structure reported to date).
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Affiliation(s)
- Michela Zuffo
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, F-91405 Orsay, France.,CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France
| | - Aurélie Gandolfini
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, F-91405 Orsay, France.,CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France
| | - Brahim Heddi
- Laboratoire de Biologie et de Pharmacologie Appliquée, CNRS UMR8113, École Normale Supérieure Paris-Saclay, F-94235 Cachan, France
| | - Anton Granzhan
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, F-91405 Orsay, France.,CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France
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21
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Bartas M, Brázda V, Bohálová N, Cantara A, Volná A, Stachurová T, Malachová K, Jagelská EB, Porubiaková O, Červeň J, Pečinka P. In-Depth Bioinformatic Analyses of Nidovirales Including Human SARS-CoV-2, SARS-CoV, MERS-CoV Viruses Suggest Important Roles of Non-canonical Nucleic Acid Structures in Their Lifecycles. Front Microbiol 2020; 11:1583. [PMID: 32719673 PMCID: PMC7347907 DOI: 10.3389/fmicb.2020.01583] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 06/17/2020] [Indexed: 12/15/2022] Open
Abstract
Non-canonical nucleic acid structures play important roles in the regulation of molecular processes. Considering the importance of the ongoing coronavirus crisis, we decided to evaluate genomes of all coronaviruses sequenced to date (stated more broadly, the order Nidovirales) to determine if they contain non-canonical nucleic acid structures. We discovered much evidence of putative G-quadruplex sites and even much more of inverted repeats (IRs) loci, which in fact are ubiquitous along the whole genomic sequence and indicate a possible mechanism for genomic RNA packaging. The most notable enrichment of IRs was found inside 5'UTR for IRs of size 12+ nucleotides, and the most notable enrichment of putative quadruplex sites (PQSs) was located before 3'UTR, inside 5'UTR, and before mRNA. This indicates crucial regulatory roles for both IRs and PQSs. Moreover, we found multiple G-quadruplex binding motifs in human proteins having potential for binding of SARS-CoV-2 RNA. Non-canonical nucleic acids structures in Nidovirales and in novel SARS-CoV-2 are therefore promising druggable structures that can be targeted and utilized in the future.
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Affiliation(s)
- Martin Bartas
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czechia
| | - Václav Brázda
- Department of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czechia
- Faculty of Chemistry, Brno University of Technology, Brno, Czechia
| | - Natália Bohálová
- Department of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czechia
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Alessio Cantara
- Department of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czechia
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Adriana Volná
- Department of Physics, Faculty of Science, University of Ostrava, Ostrava, Czechia
| | - Tereza Stachurová
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czechia
| | - Kateřina Malachová
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czechia
| | - Eva B. Jagelská
- Department of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czechia
| | - Otília Porubiaková
- Department of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czechia
- Faculty of Chemistry, Brno University of Technology, Brno, Czechia
| | - Jiří Červeň
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czechia
| | - Petr Pečinka
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czechia
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22
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Abramov G, Velyvis A, Rennella E, Wong LE, Kay LE. A methyl-TROSY approach for NMR studies of high-molecular-weight DNA with application to the nucleosome core particle. Proc Natl Acad Sci U S A 2020; 117:12836-12846. [PMID: 32457157 PMCID: PMC7293644 DOI: 10.1073/pnas.2004317117] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The development of methyl-transverse relaxation-optimized spectroscopy (methyl-TROSY)-based NMR methods, in concert with robust strategies for incorporation of methyl-group probes of structure and dynamics into the protein of interest, has facilitated quantitative studies of high-molecular-weight protein complexes. Here we develop a one-pot in vitro reaction for producing NMR quantities of methyl-labeled DNA at the C5 and N6 positions of cytosine (5mC) and adenine (6mA) nucleobases, respectively, enabling the study of high-molecular-weight DNA molecules using TROSY approaches originally developed for protein applications. Our biosynthetic strategy exploits the large number of naturally available methyltransferases to specifically methylate DNA at a desired number of sites that serve as probes of structure and dynamics. We illustrate the methodology with studies of the 153-base pair Widom DNA molecule that is simultaneously methyl-labeled at five sites, showing that high-quality 13C-1H spectra can be recorded on 100 μM samples in a few minutes. NMR spin relaxation studies of labeled methyl groups in both DNA and the H2B histone protein component of the 200-kDa nucleosome core particle (NCP) establish that methyl groups at 5mC and 6mA positions are, in general, more rigid than Ile, Leu, and Val methyl probes in protein side chains. Studies focusing on histone H2B of NCPs wrapped with either wild-type DNA or DNA methylated at all 26 CpG sites highlight the utility of NMR in investigating the structural dynamics of the NCP and how its histone core is affected through DNA methylation, an important regulator of transcription.
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Affiliation(s)
- Gili Abramov
- Department of Molecular Genetics, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Chemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Algirdas Velyvis
- Department of Molecular Genetics, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Chemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Bioscience Department, Syngenta, Jealott's Hill Research Centre, Bracknell RG42 6EY, United Kingdom
| | - Enrico Rennella
- Department of Molecular Genetics, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Chemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Leo E Wong
- Department of Molecular Genetics, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Chemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Lewis E Kay
- Department of Molecular Genetics, The University of Toronto, Toronto, ON M5S 1A8, Canada;
- Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Chemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
- Program in Molecular Medicine, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
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23
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Chu B, Zhang D, Paukstelis PJ. A DNA G-quadruplex/i-motif hybrid. Nucleic Acids Res 2020; 47:11921-11930. [PMID: 31724696 PMCID: PMC7145706 DOI: 10.1093/nar/gkz1008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/08/2019] [Accepted: 11/08/2019] [Indexed: 01/23/2023] Open
Abstract
DNA can form many structures beyond the canonical Watson–Crick double helix. It is now clear that noncanonical structures are present in genomic DNA and have biological functions. G-rich G-quadruplexes and C-rich i-motifs are the most well-characterized noncanonical DNA motifs that have been detected in vivo with either proscribed or postulated biological roles. Because of their independent sequence requirements, these structures have largely been considered distinct types of quadruplexes. Here, we describe the crystal structure of the DNA oligonucleotide, d(CCAGGCTGCAA), that self-associates to form a quadruplex structure containing two central antiparallel G-tetrads and six i-motif C–C+ base pairs. Solution studies suggest a robust structural motif capable of assembling as a tetramer of individual strands or as a dimer when composed of tandem repeats. This hybrid structure highlights the growing structural diversity of DNA and suggests that biological systems may harbor many functionally important non-duplex structures.
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Affiliation(s)
- Betty Chu
- Department of Chemistry and Biochemistry, Center for Biomolecular Structure and Organization, University of Maryland, College Park, MD 20742, USA
| | - Daoning Zhang
- Department of Chemistry and Biochemistry, Center for Biomolecular Structure and Organization, University of Maryland, College Park, MD 20742, USA
| | - Paul J Paukstelis
- Department of Chemistry and Biochemistry, Center for Biomolecular Structure and Organization, University of Maryland, College Park, MD 20742, USA
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24
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Maity A, Winnerdy FR, Chang WD, Chen G, Phan AT. Intra-locked G-quadruplex structures formed by irregular DNA G-rich motifs. Nucleic Acids Res 2020; 48:3315-3327. [PMID: 32100003 PMCID: PMC7102960 DOI: 10.1093/nar/gkaa008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 12/30/2019] [Accepted: 02/24/2020] [Indexed: 12/14/2022] Open
Abstract
G-rich DNA sequences with tracts of three or more continuous guanines (G≥3) are known to have high propensity to adopt stable G-quadruplex (G4) structures. Bioinformatic analyses suggest high prevalence of G-rich sequences with short G-tracts (G≤2) in the human genome. However, due to limited structural studies, the folding principles of such sequences remain largely unexplored and hence poorly understood. Here, we present the solution NMR structure of a sequence named AT26 consisting of irregularly spaced G2 tracts and two isolated single guanines. The structure is a four-layered G4 featuring two bi-layered blocks, locked between themselves in an unprecedented fashion making it a stable scaffold. In addition to edgewise and propeller-type loops, AT26 also harbors two V-shaped loops: a 2-nt V-shaped loop spanning two G-tetrad layers and a 0-nt V-shaped loop spanning three G-tetrad layers, which are named as VS- and VR-loop respectively, based on their distinct structural features. The intra-lock motif can be a basis for extending the G-tetrad core and a very stable intra-locked G4 can be formed by a sequence with G-tracts of various lengths including several G2 tracts. Findings from this study will aid in understanding the folding of G4 topologies from sequences containing irregularly spaced multiple short G-tracts.
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Affiliation(s)
- Arijit Maity
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Weili Denyse Chang
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Gang Chen
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
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25
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Pavc D, Wang B, Spindler L, Drevenšek-Olenik I, Plavec J, Šket P. GC ends control topology of DNA G-quadruplexes and their cation-dependent assembly. Nucleic Acids Res 2020; 48:2749-2761. [PMID: 31996902 PMCID: PMC7049726 DOI: 10.1093/nar/gkaa058] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 01/17/2020] [Accepted: 01/21/2020] [Indexed: 01/22/2023] Open
Abstract
GCn and GCnCG, where n = (G2AG4AG2), fold into well-defined, dimeric G-quadruplexes with unprecedented folding topologies in the presence of Na+ ions as revealed by nuclear magnetic resonance spectroscopy. Both G-quadruplexes exhibit unique combination of structural elements among which are two G-quartets, A(GGGG)A hexad and GCGC-quartet. Detailed structural characterization uncovered the crucial role of 5'-GC ends in formation of GCn and GCnCG G-quadruplexes. Folding in the presence of 15NH4+ and K+ ions leads to 3'-3' stacking of terminal G-quartets of GCn G-quadruplexes, while 3'-GC overhangs in GCnCG prevent dimerization. Results of the present study expand repertoire of possible G-quadruplex structures. This knowledge will be useful in DNA sequence design for nanotechnological applications that may require specific folding topology and multimerization properties.
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Affiliation(s)
- Daša Pavc
- Slovenian NMR Center, National Institute of Chemistry, 1000 Ljubljana, Slovenia
- University of Ljubljana, Faculty of Chemistry and Chemical Technology, 1000 Ljubljana, Slovenia
| | - Baifan Wang
- Slovenian NMR Center, National Institute of Chemistry, 1000 Ljubljana, Slovenia
| | - Lea Spindler
- University of Maribor, Faculty of Mechanical Engineering, 2000 Maribor, Slovenia
- Department of Complex Matter, Jozef Stefan Institute, 1000 Ljubljana, Slovenia
| | - Irena Drevenšek-Olenik
- Department of Complex Matter, Jozef Stefan Institute, 1000 Ljubljana, Slovenia
- University of Ljubljana, Faculty of Mathematics and Physics, 1000 Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, 1000 Ljubljana, Slovenia
- University of Ljubljana, Faculty of Chemistry and Chemical Technology, 1000 Ljubljana, Slovenia
- EN-FIST Center of Excellence, 1000 Ljubljana, Slovenia
| | - Primož Šket
- Slovenian NMR Center, National Institute of Chemistry, 1000 Ljubljana, Slovenia
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26
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Kotar A, Kocman V, Plavec J. Intercalation of a Heterocyclic Ligand between Quartets in a G-Rich Tetrahelical Structure. Chemistry 2020; 26:814-817. [PMID: 31750579 PMCID: PMC7004031 DOI: 10.1002/chem.201904923] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/20/2019] [Indexed: 11/20/2022]
Abstract
YES G‐rich oligonucleotide VK2 folds into an AGCGA‐quadruplex tetrahelical structure distinct and significantly different from G‐quadruplexes, even though it contains four G3 tracts. Herein, a bis‐quinolinium ligand 360A with high affinity for G‐quadruplex structures and selective telomerase inhibition is shown to strongly bind to VK2. Upon binding, 360A does not induce a conformational switch from VK2 to an expected G‐quadruplex. In contrast, NMR structural study revealed formation of a well‐defined VK2–360A complex with a 1:1 binding stoichiometry, in which 360A intercalates between GAGA‐ and GCGC‐quartets in the central cavity of VK2. This is the first high‐resolution structure of a G‐quadruplex ligand intercalating into a G‐rich tetrahelical fold. This unique mode of ligand binding into tetrahelical DNA architecture offers insights into the stabilization of an AGCGA‐quadruplex by a heterocyclic ligand and provides guidelines for rational design of novel VK2 binding molecules with selectivity for different DNA secondary structures.
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Affiliation(s)
- Anita Kotar
- National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Vojč Kocman
- National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Janez Plavec
- National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia.,EN-FIST Center of Excellence, Trg Osvobodilne fronte 13, 1000, Ljubljana, Slovenia
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27
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Grün JT, Hennecker C, Klötzner DP, Harkness RW, Bessi I, Heckel A, Mittermaier AK, Schwalbe H. Conformational Dynamics of Strand Register Shifts in DNA G-Quadruplexes. J Am Chem Soc 2019; 142:264-273. [PMID: 31815451 DOI: 10.1021/jacs.9b10367] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The complex folding energy landscape of DNA G-quadruplexes leads to numerous conformations for this functionally important class of noncanonical DNA structures. A new layer of conformational heterogeneity comes from sequences with different numbers of G-nucleotides in each of the DNA G-strands that form the four-stranded G-quartet core. The mechanisms by which G-quadruplexes transition from one folded conformation to another are currently unknown. To address this question, we studied two different G-quadruplexes, selecting a single conformation by blocking hydrogen bonding with photolabile protection groups. Upon irradiation, the block can be released and the kinetics of re-equilibration to the native conformational equilibrium can be determined by time-resolved NMR. We compared the NMR-derived refolding kinetics with data derived from thermal hysteresis folding kinetic experiments and found excellent agreement. The outlined methodological approach allows separation of K+-induced G-quadruplex formation and subsequent refolding and provides key insight into rate-limiting steps of G-quadruplex conformational dynamics.
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Affiliation(s)
- J Tassilo Grün
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany.,Center of Biomolecular Magnetic Resonance (BMRZ) , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
| | | | - Dean-Paulos Klötzner
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
| | - Robert W Harkness
- Department of Chemistry , McGill University , Montreal H3A 2K6 , Quebec , Canada
| | - Irene Bessi
- Institute of Organic Chemistry , Julius-Maximilians-University Würzburg , Würzburg 97074 , Germany
| | - Alexander Heckel
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
| | | | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany.,Center of Biomolecular Magnetic Resonance (BMRZ) , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
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28
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Winnerdy FR, Das P, Heddi B, Phan AT. Solution Structures of a G-Quadruplex Bound to Linear- and Cyclic-Dinucleotides. J Am Chem Soc 2019; 141:18038-18047. [PMID: 31661272 DOI: 10.1021/jacs.9b05642] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cyclic dinucleotides have emerged as important secondary messengers and cell signaling molecules that regulate several cell responses. A guanine-deficit G-quadruplex structure formation by a sequence containing (4n - 1) guanines, n denoting the number of G-tetrad layers, was previously reported. Here, a (4n - 1) G-quadruplex structure is shown to be capable of binding guanine-containing dinucleotides in micromolar affinity. The guanine base of the dinucleotides interacts with a vacant G-triad, forming four additional Hoogsteen hydrogen bonds to complete a G-tetrad. Solution structures of two complexes, both comprised of a (4n - 1) G-quadruplex structure, one bound to a linear dinucleotide (d(AG)) and the other to a cyclic dinucleotide (cGAMP), are solved using NMR spectroscopy. The latter suggests sufficiently strong interaction between the guanine base of the dinucleotide and the vacant G-triad, which acts as an anchor point of binding. The binding interfaces from the two solution structures provide useful information for specific ligand design. The results also infer that other guanine-containing metabolites of a similar size have the capability of binding G-quadruplexes, potentially affecting the expression of the metabolites and functionality of the bound G-quadruplexes.
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Affiliation(s)
- Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371 , Singapore
| | - Poulomi Das
- School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371 , Singapore
| | - Brahim Heddi
- School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371 , Singapore.,Laboratoire de Biologie et de Pharmacologie Appliquée , CNRS UMR 8113 , Ecole Normale Supérieure Paris-Saclay , Cachan 94235 , France
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371 , Singapore.,NTU Institute of Structural Biology , Nanyang Technological University , Singapore 636921 , Singapore
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29
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Kotar A, Rigo R, Sissi C, Plavec J. Two-quartet kit* G-quadruplex is formed via double-stranded pre-folded structure. Nucleic Acids Res 2019; 47:2641-2653. [PMID: 30590801 PMCID: PMC6411839 DOI: 10.1093/nar/gky1269] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 11/16/2018] [Accepted: 12/10/2018] [Indexed: 01/13/2023] Open
Abstract
In the promoter of c-KIT proto-oncogene, whose deregulation has been implicated in many cancers, three G-rich regions (kit1, kit* and kit2) are able to fold into G-quadruplexes. While kit1 and kit2 have been studied in depth, little information is available on kit* folding behavior despite its key role in regulation of c-KIT transcription. Notably, kit* contains consensus sites for SP1 and AP2 transcription factors. Herein, a set of complementary spectroscopic and biophysical methods reveals that kit*, d[GGCGAGGAGGGGCGTGGCCGGC], adopts a chair type antiparallel G-quadruplex with two G-quartets at physiological relevant concentrations of KCl. Heterogeneous ensemble of structures is observed in the presence of Na+ and NH4+ ions, which however stabilize pre-folded structure. In the presence of K+ ions stacking interactions of adenine and thymine residues on the top G-quartet contribute to structural stability together with a G10•C18 base pair and a fold-back motif of the five residues at the 3′-terminal under the bottom G-quartet. The 3′-tail enables formation of a bimolecular pre-folded structure that drives folding of kit* into a single G-quadruplex. Intriguingly, kinetics of kit* G-quadruplex formation matches timescale of transcriptional processes and might demonstrate interplay of kinetic and thermodynamic factors for understanding regulation of c-KIT proto-oncogene expression.
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Affiliation(s)
- Anita Kotar
- Slovenian NMR Center, National Institute of Chemistry, 1000 Ljubljana, Slovenia
| | - Riccardo Rigo
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, 35131 Padova, Italy
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, 35131 Padova, Italy
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, 1000 Ljubljana, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia.,EN-FIST Center of Excellence, 1000 Ljubljana, Slovenia
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30
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Truong THA, Winnerdy FR, Phan AT. An Unprecedented Knot‐like G‐Quadruplex Peripheral Motif. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201907740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Thi Hong Anh Truong
- School of Physical and Mathematical SciencesNanyang Technological University Singapore 637371 Singapore
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical SciencesNanyang Technological University Singapore 637371 Singapore
| | - Anh Tuân Phan
- School of Physical and Mathematical SciencesNanyang Technological University Singapore 637371 Singapore
- NTU Institute of Structural BiologyNanyang Technological University Singapore 636921 Singapore
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31
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Truong THA, Winnerdy FR, Phan AT. An Unprecedented Knot‐like G‐Quadruplex Peripheral Motif. Angew Chem Int Ed Engl 2019; 58:13834-13839. [DOI: 10.1002/anie.201907740] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Thi Hong Anh Truong
- School of Physical and Mathematical SciencesNanyang Technological University Singapore 637371 Singapore
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical SciencesNanyang Technological University Singapore 637371 Singapore
| | - Anh Tuân Phan
- School of Physical and Mathematical SciencesNanyang Technological University Singapore 637371 Singapore
- NTU Institute of Structural BiologyNanyang Technological University Singapore 636921 Singapore
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32
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Liu H, Wang R, Yu X, Shen F, Lan W, Haruehanroengra P, Yao Q, Zhang J, Chen Y, Li S, Wu B, Zheng L, Ma J, Lin J, Cao C, Li J, Sheng J, Gan J. High-resolution DNA quadruplex structure containing all the A-, G-, C-, T-tetrads. Nucleic Acids Res 2019; 46:11627-11638. [PMID: 30285239 PMCID: PMC6265469 DOI: 10.1093/nar/gky902] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 09/24/2018] [Indexed: 12/18/2022] Open
Abstract
DNA can form diverse structures, which predefine their physiological functions. Besides duplexes that carry the genetic information, quadruplexes are the most well-studied DNA structures. In addition to their important roles in recombination, replication, transcription and translation, DNA quadruplexes have also been applied as diagnostic aptamers and antidisease therapeutics. Herein we further expand the sequence and structure complexity of DNA quadruplex by presenting a high-resolution crystal structure of DNA1 (5′-AGAGAGATGGGTGCGTT-3′). This is the first quadruplex structure that contains all the internal A-, G-, C-, T-tetrads, A:T:A:T tetrads and bulged nucleotides in one single structure; as revealed by site-specific mutagenesis and biophysical studies, the central ATGGG motif plays important role in the quadruplex formation. Interestingly, our structure also provides great new insights into cation recognition, including the first-time reported Pb2+, by tetrad structures.
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Affiliation(s)
- Hehua Liu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200433, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Rui Wang
- Department of Chemistry and The RNA Institute, University at Albany, State University of New York, Albany, NY 12222, USA
| | - Xiang Yu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200433, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Fusheng Shen
- Department of Chemistry and The RNA Institute, University at Albany, State University of New York, Albany, NY 12222, USA
| | - Wenxian Lan
- State Key Laboratory of Bioorganic and Natural Product Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Shanghai 200032, China
| | - Phensinee Haruehanroengra
- Department of Chemistry and The RNA Institute, University at Albany, State University of New York, Albany, NY 12222, USA
| | - Qingqing Yao
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Jing Zhang
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Yiqing Chen
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Suhua Li
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Baixing Wu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Lina Zheng
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Jinbiao Ma
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Jinzhong Lin
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Chunyang Cao
- State Key Laboratory of Bioorganic and Natural Product Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Shanghai 200032, China
| | - Jixi Li
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200433, China.,Department of Neurology, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Jia Sheng
- Department of Chemistry and The RNA Institute, University at Albany, State University of New York, Albany, NY 12222, USA
| | - Jianhua Gan
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200433, China
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33
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Sengar A, Vandana J, Chambers VS, Di Antonio M, Winnerdy F, Balasubramanian S, Phan AT. Structure of a (3+1) hybrid G-quadruplex in the PARP1 promoter. Nucleic Acids Res 2019; 47:1564-1572. [PMID: 30551210 PMCID: PMC6379715 DOI: 10.1093/nar/gky1179] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/02/2018] [Accepted: 12/12/2018] [Indexed: 01/08/2023] Open
Abstract
Poly (ADP-ribose) polymerase 1 (PARP1) has emerged as an attractive target for cancer therapy due to its key role in DNA repair processes. Inhibition of PARP1 in BRCA-mutated cancers has been observed to be clinically beneficial. Recent genome-mapping experiments have identified a non-canonical G-quadruplex-forming sequence containing bulges within the PARP1 promoter. Structural features, like bulges, provide opportunities for selective chemical targeting of the non-canonical G-quadruplex structure within the PARP1 promoter, which could serve as an alternative therapeutic approach for the regulation of PARP1 expression. Here we report the G-quadruplex structure formed by a 23-nucleotide G-rich sequence in the PARP1 promoter. Our study revealed a three-layered intramolecular (3+1) hybrid G-quadruplex scaffold, in which three strands are oriented in one direction and the fourth in the opposite direction. This structure exhibits unique structural features such as an adenine bulge and a G·G·T base triple capping structure formed between the central edgewise loop, propeller loop and 5' flanking terminal. Given the highly important role of PARP1 in DNA repair and cancer intervention, this structure presents an attractive opportunity to explore the therapeutic potential of PARP1 inhibition via G-quadruplex DNA targeting.
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Affiliation(s)
- Anjali Sengar
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - J Jeya Vandana
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Vicki S Chambers
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Marco Di Antonio
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Shankar Balasubramanian
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge CB2 0RE, UK
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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34
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Hadži S, Kocman V, Oblak D, Plavec J, Lah J. Energetic Basis of AGCGA-Rich DNA Folding into a Tetrahelical Structure. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201813502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- San Hadži
- Faculty of Chemistry and Chemical Technology; University of Ljubljana; Večna pot 113 Ljubljana Slovenia
| | - Vojč Kocman
- National Institute of Chemistry; Hajdrihova 19 Slovenia
| | - Domen Oblak
- Faculty of Chemistry and Chemical Technology; University of Ljubljana; Večna pot 113 Ljubljana Slovenia
| | - Janez Plavec
- Faculty of Chemistry and Chemical Technology; University of Ljubljana; Večna pot 113 Ljubljana Slovenia
- National Institute of Chemistry; Hajdrihova 19 Slovenia
| | - Jurij Lah
- Faculty of Chemistry and Chemical Technology; University of Ljubljana; Večna pot 113 Ljubljana Slovenia
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35
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Hadži S, Kocman V, Oblak D, Plavec J, Lah J. Energetic Basis of AGCGA‐Rich DNA Folding into a Tetrahelical Structure. Angew Chem Int Ed Engl 2019; 58:2387-2391. [DOI: 10.1002/anie.201813502] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Indexed: 11/09/2022]
Affiliation(s)
- San Hadži
- Faculty of Chemistry and Chemical TechnologyUniversity of Ljubljana Večna pot 113 Ljubljana Slovenia
| | - Vojč Kocman
- National Institute of Chemistry Hajdrihova 19 Slovenia
| | - Domen Oblak
- Faculty of Chemistry and Chemical TechnologyUniversity of Ljubljana Večna pot 113 Ljubljana Slovenia
| | - Janez Plavec
- Faculty of Chemistry and Chemical TechnologyUniversity of Ljubljana Večna pot 113 Ljubljana Slovenia
- National Institute of Chemistry Hajdrihova 19 Slovenia
| | - Jurij Lah
- Faculty of Chemistry and Chemical TechnologyUniversity of Ljubljana Večna pot 113 Ljubljana Slovenia
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36
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Bakalar B, Heddi B, Schmitt E, Mechulam Y, Phan AT. A Minimal Sequence for Left-Handed G-Quadruplex Formation. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201812628] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Blaž Bakalar
- School of Physical and Mathematical Sciences; Nanyang Technological University; Singapore 637371 Singapore
- School of Biological Sciences; Nanyang Technological University; Singapore 637551 Singapore
| | - Brahim Heddi
- School of Physical and Mathematical Sciences; Nanyang Technological University; Singapore 637371 Singapore
- Laboratoire de Biologie et Pharmacologie Appliquée, CNRS; Ecole Normale Supérieure Paris-Saclay; 94235 Cachan France
| | - Emmanuelle Schmitt
- Laboratoire de Biochimie, UMR 7654, CNRS; Ecole Polytechnique; 91128 Palaiseau France
| | - Yves Mechulam
- Laboratoire de Biochimie, UMR 7654, CNRS; Ecole Polytechnique; 91128 Palaiseau France
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences; Nanyang Technological University; Singapore 637371 Singapore
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37
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Bakalar B, Heddi B, Schmitt E, Mechulam Y, Phan AT. A Minimal Sequence for Left-Handed G-Quadruplex Formation. Angew Chem Int Ed Engl 2019; 58:2331-2335. [PMID: 30481397 DOI: 10.1002/anie.201812628] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Indexed: 12/20/2022]
Abstract
Recently, we observed the first example of a left-handed G-quadruplex structure formed by natural DNA, named Z-G4. We analysed the Z-G4 structure and inspected its primary 28-nt sequence in order to identify motifs that convey the unique left-handed twist. Using circular dichroism spectroscopy, NMR spectroscopy, and X-ray crystallography, we revealed a minimal sequence motif of 12 nt (GTGGTGGTGGTG) for formation of the left-handed DNA G-quadruplex, which is found to be highly abundant in the human genome. A systematic analysis of thymine loop mutations revealed a moderate sequence tolerance, which would further broaden the space of sequences prone to left-handed G-quadruplex formation.
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Affiliation(s)
- Blaž Bakalar
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Brahim Heddi
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.,Laboratoire de Biologie et Pharmacologie Appliquée, CNRS, Ecole Normale Supérieure Paris-Saclay, 94235, Cachan, France
| | - Emmanuelle Schmitt
- Laboratoire de Biochimie, UMR 7654, CNRS, Ecole Polytechnique, 91128, Palaiseau, France
| | - Yves Mechulam
- Laboratoire de Biochimie, UMR 7654, CNRS, Ecole Polytechnique, 91128, Palaiseau, France
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
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38
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Genome-wide Identification of Structure-Forming Repeats as Principal Sites of Fork Collapse upon ATR Inhibition. Mol Cell 2018; 72:222-238.e11. [PMID: 30293786 DOI: 10.1016/j.molcel.2018.08.047] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 07/11/2018] [Accepted: 08/30/2018] [Indexed: 01/22/2023]
Abstract
DNA polymerase stalling activates the ATR checkpoint kinase, which in turn suppresses fork collapse and breakage. Herein, we describe use of ATR inhibition (ATRi) as a means to identify genomic sites of problematic DNA replication in murine and human cells. Over 500 high-resolution ATR-dependent sites were ascertained using two distinct methods: replication protein A (RPA)-chromatin immunoprecipitation (ChIP) and breaks identified by TdT labeling (BrITL). The genomic feature most strongly associated with ATR dependence was repetitive DNA that exhibited high structure-forming potential. Repeats most reliant on ATR for stability included structure-forming microsatellites, inverted retroelement repeats, and quasi-palindromic AT-rich repeats. Notably, these distinct categories of repeats differed in the structures they formed and their ability to stimulate RPA accumulation and breakage, implying that the causes and character of replication fork collapse under ATR inhibition can vary in a DNA-structure-specific manner. Collectively, these studies identify key sources of endogenous replication stress that rely on ATR for stability.
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39
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Zhu L, Zhou J, Xu G, Li C, Ling P, Liu B, Ju H, Lei J. DNA quadruplexes as molecular scaffolds for controlled assembly of fluorogens with aggregation-induced emission. Chem Sci 2018; 9:2559-2566. [PMID: 29732135 PMCID: PMC5911820 DOI: 10.1039/c8sc00001h] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 01/28/2018] [Indexed: 01/07/2023] Open
Abstract
Aggregation-induced emission (AIE) can be generated due to the restriction of intramolecular motions. The controllable assembly of fluorogens with AIE properties (AIEgens) is able to provide a new opportunity for precise manipulation of fluorescent signal transduction. Here, a tetrapod DNA quadruplex (TP-G4) was designed as a molecular scaffold for assembly and precise modulation of light emission of an oligonucleotide-grafted fluorogen with aggregation-induced emission (Oligo-AIEgen). The Oligo-AIEgen was synthesized by attaching the AIEgen to the 3'-terminus of the oligonucleotide through a dibenzylcyclooctyne mediated coupling reaction. The AIEgen emitted no detectable fluorescence in the context of a double-stranded structure. When hybridized to the parallel-stranded TP-G4, several AIEgens were located in close proximity to generate fluorescence. The fluorescence intensity has been precisely regulated by manipulation of the spacer length between the core structure of the scaffold and AIEgen, as well as by altering the quartet number of the G-quadruplex. Similar control of fluorescence was also demonstrated using tetramolecular and bimolecular i-motif quadruplex structures as the scaffolds. These scaffolds provide a proof of concept on the manipulation of molecular interactions, which forms a universal molecular tool for the design of new biosensing strategies.
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Affiliation(s)
- Longyi Zhu
- State Key Laboratory of Analytical Chemistry for Life Science , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China . ;
| | - Jun Zhou
- State Key Laboratory of Analytical Chemistry for Life Science , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China . ;
| | - Guohua Xu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics , Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , China
| | - Conggang Li
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics , Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , China
| | - Pinghua Ling
- State Key Laboratory of Analytical Chemistry for Life Science , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China . ;
| | - Bin Liu
- Department of Chemical and Biomolecular Engineering , National University of Singapore , 4 Science Drive 4 , Singapore 117585 , Singapore .
| | - Huangxian Ju
- State Key Laboratory of Analytical Chemistry for Life Science , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China . ;
| | - Jianping Lei
- State Key Laboratory of Analytical Chemistry for Life Science , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China . ;
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40
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O'Hagan MP, Mergny JL, Waller ZAE. G-quadruplexes in Prague: A Bohemian Rhapsody. Biochimie 2018; 147:170-180. [PMID: 29452278 DOI: 10.1016/j.biochi.2018.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 02/07/2018] [Indexed: 12/26/2022]
Abstract
The Sixth International Meeting on Quadruplex Nucleic Acids was held at the Hotel Internationale in Prague, Czech Republic from 31 May - 3 June 2017. A vibrant interdisciplinary community of over 300 scientists gathered to share their newest results in this exciting field and exchange ideas for further investigations.
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Affiliation(s)
- Michael Paul O'Hagan
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS1 1TS, UK.
| | - Jean-Louis Mergny
- Univ. Bordeaux, ARNA Laboratory, Inserm U1212, CNRS UMR 5320, IECB, F-33600, France; Institute of Biophysics, AS CR, v.v.i., Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Zoë Ann Ella Waller
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK; Centre for Molecular and Structural Biochemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
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41
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Greco ML, Kotar A, Rigo R, Cristofari C, Plavec J, Sissi C. Coexistence of two main folded G-quadruplexes within a single G-rich domain in the EGFR promoter. Nucleic Acids Res 2017; 45:10132-10142. [PMID: 28973461 PMCID: PMC5737278 DOI: 10.1093/nar/gkx678] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 07/22/2017] [Indexed: 12/15/2022] Open
Abstract
EGFR is an oncogene which codifies for a tyrosine kinase receptor that represents an important target for anticancer therapy. Indeed, several human cancers showed an upregulation of the activity of this protein. The promoter of this gene contains some G-rich domains, thus representing a yet unexplored point of intervention to potentially silence this gene. Here, we explore the conformational equilibria of a 30-nt long sequence located at position −272 (EGFR-272). By merging spectroscopic and electrophoretic analysis performed on the wild-type sequence as well as on a wide panel of related mutants, we were able to prove that in potassium ion containing solution this sequence folds into two main G-quadruplex structures, one parallel and one hybrid. They show comparable thermal stabilities and affinities for the metal ion and, indeed, they are always co-present in solution. The folding process is driven by a hairpin occurring in the domain corresponding to the terminal loop which works as an important stabilizing element for both the identified G-quadruplex arrangements.
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Affiliation(s)
- Maria L Greco
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, v. Marzolo 5, Padova 35131, Italy
| | - Anita Kotar
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Riccardo Rigo
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, v. Marzolo 5, Padova 35131, Italy
| | - Camilla Cristofari
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, v. Marzolo 5, Padova 35131, Italy
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.,EN-FIST Center of Excellence, Trg OF 13, 1000 Ljubljana, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, v. Marzolo 5, Padova 35131, Italy
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42
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Mir B, Serrano I, Buitrago D, Orozco M, Escaja N, González C. Prevalent Sequences in the Human Genome Can Form Mini i-Motif Structures at Physiological pH. J Am Chem Soc 2017; 139:13985-13988. [DOI: 10.1021/jacs.7b07383] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bartomeu Mir
- Inorganic and Organic
Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
- BIOESTRAN associated unit UB-CSIC, 08028 Barcelona, Spain
| | - Israel Serrano
- Instituto de Química Física ‘Rocasolano’, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Diana Buitrago
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
- Departament de Bioquímica
i Biomedicina, Facultat de Biologia, Universitat de Barcelona, Spain
| | - Núria Escaja
- Inorganic and Organic
Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
- BIOESTRAN associated unit UB-CSIC, 08028 Barcelona, Spain
| | - Carlos González
- Instituto de Química Física ‘Rocasolano’, CSIC, Serrano 119, 28006 Madrid, Spain
- BIOESTRAN associated unit UB-CSIC, 08028 Barcelona, Spain
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43
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Rigo R, Sissi C. Characterization of G4-G4 Crosstalk in the c-KIT Promoter Region. Biochemistry 2017; 56:4309-4312. [PMID: 28763217 DOI: 10.1021/acs.biochem.7b00660] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The proximal promoter of c-KIT contains a peculiar domain that consists of three short G-rich sequences that are close together and can fold into noncanonical DNA secondary structures called G-quadruplexes (G4). Here, we focused on a sequence containing two consecutive G4 (kit2 and kit*). By electrophoretic, surface plasmon resonance, and spectroscopic techniques, we demonstrated that they retain the ability to fold into G4 upon being inserted into the extended sequence. Here, we highlighted the occurrence of crosstalk between the two forming units. This previously unexplored G4-G4 interaction modulates both the conformation and the stability of the overall arrangement of the c-KIT promoter. It is not supported by stacking of single nucleotides but refers to a G4-G4 interaction surface surrounded by a two-nucleotides loop that might represent a reliable unprecedented target for anticancer therapy.
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Affiliation(s)
- Riccardo Rigo
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova , Via Marzolo 5, 35131 Padova, Italy
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova , Via Marzolo 5, 35131 Padova, Italy
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