1
|
Libera V, Fasolato C, Ripanti F, Catalini S, Bertini L, Petrillo C, Schirò G, D'Amico F, Rossi B, Paciaroni A, Comez L. Molecular mechanisms behind BRACO19 and human telomeric G-quadruplex interaction. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 322:124684. [PMID: 38981290 DOI: 10.1016/j.saa.2024.124684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 06/12/2024] [Accepted: 06/18/2024] [Indexed: 07/11/2024]
Abstract
Human telomeres (HTs) can form DNA G-quadruplex (G4), an attractive target for anticancer and antiviral drugs. HT-G4s exhibit inherent structural polymorphism, posing challenges for understanding their specific recognition by ligands. Here, we aim to explore the impact of different topologies within a small segment of the HT (Tel22) on its interaction with BRACO19, a rationally designed G4 ligand with high quadruplex affinity, already employed in in-vivo treatments. Our multi-technique approach is based on the combined use of a set of contactless spectroscopic tools. Circular dichroism and UV resonance Raman spectroscopy probe ligand-induced conformational changes in the G4 sequence, while UV-visible absorption, coupled with steady-state fluorescence spectroscopy, provides further insights into the electronic features of the complex, exploiting the photoresponsive properties of BRACO19. Overall, we find that modifying the topology of the unbound Tel22 through cations (K+ or Na+), serves as a critical determinant for ligand interactions and binding modes, thus influencing the HT-G4's assembly capabilities. Furthermore, we show how fluorescence serves as a valuable probe for recognizing cation-driven multimeric structures, which may be present in living organisms, giving rise to pathological forms.
Collapse
Affiliation(s)
- Valeria Libera
- Department of Physics and Geology, University of Perugia, via Alessandro Pascoli, 06123, Perugia, Italy.
| | - Claudia Fasolato
- Institute for Complex System, National Research Council (ISC-CNR), Piazzale Aldo Moro, 5, 00185, Roma, Italy
| | - Francesca Ripanti
- Department of Physics and Geology, University of Perugia, via Alessandro Pascoli, 06123, Perugia, Italy
| | - Sara Catalini
- Department of Physics and Geology, University of Perugia, via Alessandro Pascoli, 06123, Perugia, Italy; European Laboratory for Non-Linear Spectroscopy (LENS), via Nello Carrara 1, 50019, Sesto Fiorentino (FI), Italy; National Research Council-National Institute of Optics (CNR-INO), Largo Fermi 6, 50125, Florence, Italy
| | - Luca Bertini
- Department of Physics and Geology, University of Perugia, via Alessandro Pascoli, 06123, Perugia, Italy
| | - Caterina Petrillo
- Department of Physics and Geology, University of Perugia, via Alessandro Pascoli, 06123, Perugia, Italy
| | - Giorgio Schirò
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, F-38044, Grenoble, France
| | - Francesco D'Amico
- Elettra - Sincrotrone Trieste S.C.p.A, s.s. 14 km 163, 500 in Area Science Park, 34149, Trieste, Italy
| | - Barbara Rossi
- Elettra - Sincrotrone Trieste S.C.p.A, s.s. 14 km 163, 500 in Area Science Park, 34149, Trieste, Italy
| | - Alessandro Paciaroni
- Department of Physics and Geology, University of Perugia, via Alessandro Pascoli, 06123, Perugia, Italy
| | - Lucia Comez
- CNR-IOM - Istituto Officina dei Materiali, Via Alessandro Pascoli, 06123, Perugia, Italy.
| |
Collapse
|
2
|
Vianney YM, Dierks D, Weisz K. Structural Differences at Quadruplex-Duplex Interfaces Enable Ligand-Induced Topological Transitions. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2309891. [PMID: 38477454 PMCID: PMC11200018 DOI: 10.1002/advs.202309891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 02/13/2024] [Indexed: 03/14/2024]
Abstract
Quadruplex-duplex (QD) junctions, which represent unique structural motifs of both biological and technological significance, have been shown to constitute high-affinity binding sites for various ligands. A QD hybrid construct based on a human telomeric sequence, which harbors a duplex stem-loop in place of a short lateral loop, is structurally characterized by NMR. It folds into two major species with a (3+1) hybrid and a chair-type (2+2) antiparallel quadruplex domain coexisting in a K+ buffer solution. The antiparallel species is stabilized by an unusual capping structure involving a thymine and protonated adenine base AH+ of the lateral loop facing the hairpin duplex to form a T·AH+·G·C quartet with the interfacial G·C base pair at neutral pH. Addition and binding of Phen-DC3 to the QD hybrid mixture by its partial intercalation at corresponding QD junctions leads to a topological transition with exclusive formation of the (3+1) hybrid fold. In agreement with the available experimental data, such an unprecedented discrimination of QD junctions by a ligand can be rationalized following an induced fit mechanism.
Collapse
Affiliation(s)
- Yoanes Maria Vianney
- Institut für BiochemieUniversität GreifswaldFelix‐Hausdorff‐Str. 4D‐17489GreifswaldGermany
| | - Dorothea Dierks
- Institut für BiochemieUniversität GreifswaldFelix‐Hausdorff‐Str. 4D‐17489GreifswaldGermany
| | - Klaus Weisz
- Institut für BiochemieUniversität GreifswaldFelix‐Hausdorff‐Str. 4D‐17489GreifswaldGermany
| |
Collapse
|
3
|
Vianney YM, Jana J, Weisz K. A pH-Responsive Topological Switch Based on a DNA Quadruplex-Duplex Hybrid. Chemistry 2024; 30:e202400722. [PMID: 38497675 DOI: 10.1002/chem.202400722] [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: 02/22/2024] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 03/19/2024]
Abstract
A guanine-rich oligonucleotide based on a human telomeric sequence but with the first three-nucleotide intervening stretch replaced by a putative 15-nucleotide hairpin-forming sequence shows a pH-dependent folding into different quadruplex-duplex hybrids in a potassium containing buffer. At slightly acidic pH, the quadruplex domain adopts a chair-type conformation. Upon increasing the pH, a transition with a midpoint close to neutral pH to a major and minor (3+1) hybrid topology with either a coaxially stacked or orthogonally oriented duplex stem-loop occurs. NMR-derived high-resolution structures reveal that an adenine protonation is prerequisite for the formation of a non-canonical base quartet, capping the outer G-tetrad at the quadruplex-duplex interface and stabilizing the antiparallel chair conformation in an acidic environment. Being directly associated with interactions at the quadruplex-duplex interface, this unique pH-dependent topological transition is fully reversible. Coupled with a conformation-sensitive optical readout demonstrated as a proof of concept using the fluorescent dye thiazole orange, the present quadruplex-duplex hybrid architecture represents a potentially valuable pH-sensing system responsive in a physiological pH range of 7±1.
Collapse
Affiliation(s)
- Yoanes Maria Vianney
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489, Greifswald, Germany
| | - Jagannath Jana
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489, Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489, Greifswald, Germany
| |
Collapse
|
4
|
Zhang Z, Mlýnský V, Krepl M, Šponer J, Stadlbauer P. Mechanical Stability and Unfolding Pathways of Parallel Tetrameric G-Quadruplexes Probed by Pulling Simulations. J Chem Inf Model 2024; 64:3896-3911. [PMID: 38630447 PMCID: PMC11094737 DOI: 10.1021/acs.jcim.4c00227] [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: 02/08/2024] [Revised: 04/02/2024] [Accepted: 04/02/2024] [Indexed: 05/14/2024]
Abstract
Guanine quadruplex (GQ) is a noncanonical nucleic acid structure formed by guanine-rich DNA and RNA sequences. Folding of GQs is a complex process, where several aspects remain elusive, despite being important for understanding structure formation and biological functions of GQs. Pulling experiments are a common tool for acquiring insights into the folding landscape of GQs. Herein, we applied a computational pulling strategy─steered molecular dynamics (SMD) simulations─in combination with standard molecular dynamics (MD) simulations to explore the unfolding landscapes of tetrameric parallel GQs. We identified anisotropic properties of elastic conformational changes, unfolding transitions, and GQ mechanical stabilities. Using a special set of structural parameters, we found that the vertical component of pulling force (perpendicular to the average G-quartet plane) plays a significant role in disrupting GQ structures and weakening their mechanical stabilities. We demonstrated that the magnitude of the vertical force component depends on the pulling anchor positions and the number of G-quartets. Typical unfolding transitions for tetrameric parallel GQs involve base unzipping, opening of the G-stem, strand slippage, and rotation to cross-like structures. The unzipping was detected as the first and dominant unfolding event, and it usually started at the 3'-end. Furthermore, results from both SMD and standard MD simulations indicate that partial spiral conformations serve as a transient ensemble during the (un)folding of GQs.
Collapse
Affiliation(s)
- Zhengyue Zhang
- Institute
of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
- CEITEC−Central
European Institute of Technology, Masaryk
University, Kamenice
5, Brno 625 00, Czech Republic
- National
Center for Biomolecular Research,
Faculty of Science, Masaryk University, Kamenice 5, Brno 625 00, Czech Republic
| | - Vojtěch Mlýnský
- Institute
of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
| | - Miroslav Krepl
- Institute
of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
| | - Jiří Šponer
- Institute
of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
| | - Petr Stadlbauer
- Institute
of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
| |
Collapse
|
5
|
Attanayake K, Mahmud S, Banerjee C, Sharif D, Rahman M, Majuta S, DeBastiani A, Sultana MN, Foroushani SH, Li C, Li P, Valentine SJ. Examining DNA Structures with In-droplet Hydrogen/Deuterium Exchange Mass Spectrometry. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2024; 499:117231. [PMID: 38854816 PMCID: PMC11156224 DOI: 10.1016/j.ijms.2024.117231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Capillary vibrating sharp-edge spray ionization (cVSSI) combined with hydrogen/deuterium exchange-mass spectrometry (HDX-MS) has been utilized to characterize different solution-phase DNA conformers including DNA G-quadruplex topologies as well as triplex DNA and duplex DNA. In general, G-quadruplex DNA shows a wide range of protection of hydrogens extending from ~12% to ~21% deuterium incorporation. Additionally, the DNA sequences selected to represent parallel, antiparallel, and hybrid G-quadruplex topologies exhibit slight differences in deuterium uptake levels which appear to loosely relate to overall conformer stability. Notably, the exchange level for one of the hybrid sequence sub topologies of G-quadruplex DNA (24 TTG) is significantly different (compared with the others studied here) despite the DNA sequences being highly comparable. For the quadruplex-forming sequences, correlation analysis suggests protection of base hydrogens involved in tetrad hydrogen bonding. For duplex DNA ~19% deuterium incorporation is observed while only ~16% is observed for triplex DNA. This increased protection of hydrogens may be due to the added backbone scaffolding and Hoogsteen base pairing of the latter species. These experiments lay the groundwork for future studies aimed at determining the structural source of this protection as well as the applicability of the approach for ascertaining different oligonucleotide folds, co-existing conformations, and/or overall conformer flexibility.
Collapse
Affiliation(s)
- Kushani Attanayake
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Sultan Mahmud
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Chandrima Banerjee
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Daud Sharif
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Mohammad Rahman
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Sandra Majuta
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Anthony DeBastiani
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Mst Nigar Sultana
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | | | - Chong Li
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Peng Li
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Stephen J Valentine
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| |
Collapse
|
6
|
Farag M, Mouawad L. Comprehensive analysis of intramolecular G-quadruplex structures: furthering the understanding of their formalism. Nucleic Acids Res 2024; 52:3522-3546. [PMID: 38512075 DOI: 10.1093/nar/gkae182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 02/16/2024] [Accepted: 03/01/2024] [Indexed: 03/22/2024] Open
Abstract
G-quadruplexes (G4) are helical structures found in guanine-rich DNA or RNA sequences. Generally, their formalism is based on a few dozen structures, which can produce some inconsistencies or incompleteness. Using the website ASC-G4, we analyzed the structures of 333 intramolecular G4s, of all types, which allowed us to clarify some key concepts and present new information. To each of the eight distinguishable topologies corresponds a groove-width signature and a predominant glycosidic configuration (gc) pattern governed by the directions of the strands. The relative orientations of the stacking guanines within the strands, which we quantified and related to their vertical gc successions, determine the twist and tilt of the helices. The latter impact the minimum groove widths, which represent the space available for lateral ligand binding. The G4 four helices have similar twists, even when these twists are irregular, meaning that they have various angles along the strands. Despite its importance, the vertical gc succession has no strict one-to-one relationship with the topology, which explains the discrepancy between some topologies and their corresponding circular dichroism spectra. This study allowed us to introduce the new concept of platypus G4s, which are structures with properties corresponding to several topologies.
Collapse
Affiliation(s)
- Marc Farag
- Chemistry and Modeling for the Biology of Cancer, CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, Université Paris-Saclay, CS 90030, 91401 ORSAYCedex, France
| | - Liliane Mouawad
- Chemistry and Modeling for the Biology of Cancer, CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, Université Paris-Saclay, CS 90030, 91401 ORSAYCedex, France
| |
Collapse
|
7
|
Jurkowski M, Kogut M, Sappati S, Czub J. Why Are Left-Handed G-Quadruplexes Scarce? J Phys Chem Lett 2024; 15:3142-3148. [PMID: 38477716 PMCID: PMC10961827 DOI: 10.1021/acs.jpclett.3c03589] [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: 12/23/2023] [Revised: 02/27/2024] [Accepted: 03/08/2024] [Indexed: 03/14/2024]
Abstract
G-quadruplexes (G4s) are nucleic acid structures crucial for the regulation of gene expression and genome maintenance. While they hold promise as nanodevice components, achieving desired G4 folds requires understanding the interplay between stability and structural properties, like helicity. Although right-handed G4 structures dominate the experimental data, the molecular basis for this preference over left-handed helicity is unclear. To address this, we employ all-atom molecular dynamics simulations and quantum chemical methods. Our results reveal that right-handed G4s exhibit greater thermodynamic and kinetic stability as a result of favorable sugar-phosphate backbone conformations in guanine tracts. Moreover, while hydrogen-bonding patterns influence helicity-specific G4 loop conformations, they minimally affect stability differences. We also elucidate the strong correlation between helicity and the strand progression direction, essential for G4 structures. These findings deepen our understanding of G4s, providing molecular-level insights into their structural and energetic preferences, which could inform the design of novel nanodevices.
Collapse
Affiliation(s)
- Michał Jurkowski
- Department
of Physical Chemistry, Gdańsk University
of Technology, Narutowicza Street 11/12, 80-233 Gdańsk, Poland
| | - Mateusz Kogut
- Department
of Physical Chemistry, Gdańsk University
of Technology, Narutowicza Street 11/12, 80-233 Gdańsk, Poland
| | - Subrahmanyam Sappati
- Department
of Physical Chemistry, Gdańsk University
of Technology, Narutowicza Street 11/12, 80-233 Gdańsk, Poland
- BioTechMed
Center, Gdańsk University of Technology, Narutowicza Street 11/12, 80-233 Gdańsk, Poland
| | - Jacek Czub
- Department
of Physical Chemistry, Gdańsk University
of Technology, Narutowicza Street 11/12, 80-233 Gdańsk, Poland
- BioTechMed
Center, Gdańsk University of Technology, Narutowicza Street 11/12, 80-233 Gdańsk, Poland
| |
Collapse
|
8
|
Pokorná P, Mlýnský V, Bussi G, Šponer J, Stadlbauer P. Molecular dynamics simulations reveal the parallel stranded d(GGGA) 3GGG DNA quadruplex folds via multiple paths from a coil-like ensemble. Int J Biol Macromol 2024; 261:129712. [PMID: 38286387 DOI: 10.1016/j.ijbiomac.2024.129712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/10/2024] [Accepted: 01/16/2024] [Indexed: 01/31/2024]
Abstract
G-quadruplexes (G4s) are non-canonical nucleic acid structures that fold through complex processes. Characterization of the G4 folding landscape may help to elucidate biological roles of G4s but is challenging both experimentally and computationally. Here, we achieved complete folding of a three-quartet parallel DNA G4 with (GGGA)3GGG sequence using all-atom explicit-solvent enhanced-sampling molecular dynamics (MD) simulations. The simulations suggested early formation of guanine stacks in the G-tracts, which behave as semi-rigid blocks in the folding process. The folding continues via the formation of a collapsed compact coil-like ensemble. Structuring of the G4 from the coil then proceeds via various cross-like, hairpin, slip-stranded and two-quartet ensembles and can bypass the G-triplex structure. Folding of the parallel G4 does not appear to involve any salient intermediates and is a multi-pathway process. We also carried out an extended set of simulations of parallel G-hairpins. While parallel G-hairpins are extremely unstable when isolated, they are more stable inside the coil structure. On the methodology side, we show that the AMBER DNA force field predicts the folded G4 to be less stable than the unfolded ensemble, uncovering substantial force-field issues. Overall, we provide unique atomistic insights into the folding landscape of parallel-stranded G4 but also reveal limitations of current state-of-the-art MD techniques.
Collapse
Affiliation(s)
- Pavlína Pokorná
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
| | - Vojtěch Mlýnský
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), via Bonomea 265, Trieste 34136, Italy
| | - Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic
| | - Petr Stadlbauer
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 61200, Czech Republic.
| |
Collapse
|
9
|
Wang C, Xu G, Liu X, Jiang L, Zhou X, Liu M, Li C. 19F Nuclear Magnetic Resonance Fingerprinting Technique for Identifying and Quantifying G-Quadruplex Topology in Human Telomeric Overhangs. J Am Chem Soc 2024; 146:4741-4751. [PMID: 38346932 DOI: 10.1021/jacs.3c12247] [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: 02/22/2024]
Abstract
G-quadruplexes (G4s) are noncanonical nucleic acid secondary structures with diverse topological features and biological roles. Human telomeric (Htelo) overhangs consisting of TTAGGG repeats can fold into G4s that adopt different topologies under physiological conditions. These G4s are potential targets for anticancer drugs. Despite intensive research, the existence and topology of G4s at Htelo overhangs in vivo are still unclear because there is no method to distinguish and quantify the topology of Htelo overhangs with native lengths that can form more than three tandem G4s in living cells. Herein, we present a novel 19F chemical shift fingerprinting technique to identify and quantify the topology of the Htelo overhangs up to five G-quadruplexes (G4s) and 120 nucleotides long both in vitro and in living cells. Our results show that longer overhang sequences tend to form stable G4s at the 5'- and 3'-ends, while the interior G4s are dynamic and "sliding" along the sequence, with TTA or 1-3 TTAGGG repeats as a linker. Each G4 in the longer overhang is conformationally heterogeneous, but the predominant ones are hybrid-2, two- or three-tetrad antiparallel, and hybrid-1 at the 5'-terminal, interior, and 3'-terminal, respectively. Additionally, we observed a distinct behavior of different lengths of telomeric sequences in living cells, suggesting that the overhang length and protein accessibility are related to its function. This technique provides a powerful tool for quickly identifying the folding topology and relative population of long Htelo overhangs, which may provide valuable insights into telomere functionality and be beneficial for structure-based anticancer drug development targeting G4s.
Collapse
Affiliation(s)
- Chen Wang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guohua Xu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Xiaoli Liu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Ling Jiang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Xin Zhou
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Maili Liu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Conggang Li
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| |
Collapse
|
10
|
Jana J, Vianney YM, Weisz K. Impact of loop length and duplex extensions on the design of hybrid-type G-quadruplexes. Chem Commun (Camb) 2024; 60:854-857. [PMID: 38131370 DOI: 10.1039/d3cc05625b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
A G-rich core sequence G3-TCA-G3-T1,2-G3-T1,2-G3 can be designed to fold into a parallel or into two different (3+1) hybrid-type G-quadruplexes, among them an elusive topology with one lateral followed by two propeller loops. Favored folds can be rationalized based on the number of intervening thymidines and on additional complementary flanking sequences.
Collapse
Affiliation(s)
- Jagannath Jana
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff Str. 4, Greifswald D-17489, Germany.
| | - Yoanes Maria Vianney
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff Str. 4, Greifswald D-17489, Germany.
| | - Klaus Weisz
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff Str. 4, Greifswald D-17489, Germany.
| |
Collapse
|
11
|
Zareie AR, Dabral P, Verma SC. G-Quadruplexes in the Regulation of Viral Gene Expressions and Their Impacts on Controlling Infection. Pathogens 2024; 13:60. [PMID: 38251367 PMCID: PMC10819198 DOI: 10.3390/pathogens13010060] [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: 11/15/2023] [Revised: 01/05/2024] [Accepted: 01/05/2024] [Indexed: 01/23/2024] Open
Abstract
G-quadruplexes (G4s) are noncanonical nucleic acid structures that play significant roles in regulating various biological processes, including replication, transcription, translation, and recombination. Recent studies have identified G4s in the genomes of several viruses, such as herpes viruses, hepatitis viruses, and human coronaviruses. These structures are implicated in regulating viral transcription, replication, and virion production, influencing viral infectivity and pathogenesis. G4-stabilizing ligands, like TMPyP4, PhenDC3, and BRACO19, show potential antiviral properties by targeting and stabilizing G4 structures, inhibiting essential viral life-cycle processes. This review delves into the existing literature on G4's involvement in viral regulation, emphasizing specific G4-stabilizing ligands. While progress has been made in understanding how these ligands regulate viruses, further research is needed to elucidate the mechanisms through which G4s impact viral processes. More research is necessary to develop G4-stabilizing ligands as novel antiviral agents. The increasing body of literature underscores the importance of G4s in viral biology and the development of innovative therapeutic strategies against viral infections. Despite some ligands' known regulatory effects on viruses, a deeper comprehension of the multifaceted impact of G4s on viral processes is essential. This review advocates for intensified research to unravel the intricate relationship between G4s and viral processes, paving the way for novel antiviral treatments.
Collapse
Affiliation(s)
| | | | - Subhash C. Verma
- Department of Microbiology and Immunology, University of Nevada, Reno School of Medicine, 1664 N Virginia Street, Reno, NV 89557, USA; (A.R.Z.); (P.D.)
| |
Collapse
|
12
|
Lopina OD, Sidorenko SV, Fedorov DA, Klimanova EA. G-Quadruplexes as Sensors of Intracellular Na+/K + Ratio: Potential Role in Regulation of Transcription and Translation. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:S262-S277. [PMID: 38621755 DOI: 10.1134/s0006297924140153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/06/2023] [Accepted: 11/11/2023] [Indexed: 04/17/2024]
Abstract
Data on the structure of G-quadruplexes, noncanonical nucleic acid forms, supporting an idea of their potential participation in regulation of gene expression in response to the change in intracellular Na+i/K+i ratio are considered in the review. Structural variety of G-quadruplexes, role of monovalent cations in formation of this structure, and thermodynamic stability of G-quadruplexes are described. Data on the methods of their identification in the cells and biological functions of these structures are presented. Analysis of information about specific interactions of G-quadruplexes with some proteins was conducted, and their potential participation in the development of some pathological conditions, in particular, cancer and neurodegenerative diseases, is considered. Special attention is given to the plausible role of G-quadruplexes as sensors of intracellular Na+i/K+i ratio, because alteration of this parameter affects folding of G-quadruplexes changing their stability and, thereby, organization of the regulatory elements of nucleic acids. The data presented in the conclusion section demonstrate significant change in the expression of some early response genes under certain physiological conditions of cells and tissues depending on the intracellular Na+i/K+i ratio.
Collapse
Affiliation(s)
- Olga D Lopina
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia.
| | | | - Dmitry A Fedorov
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | | |
Collapse
|
13
|
Vianney YM, Schröder N, Jana J, Chojetzki G, Weisz K. Showcasing Different G-Quadruplex Folds of a G-Rich Sequence: Between Rule-Based Prediction and Butterfly Effect. J Am Chem Soc 2023; 145:22194-22205. [PMID: 37751488 DOI: 10.1021/jacs.3c08336] [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: 09/28/2023]
Abstract
In better understanding the interactions of G-quadruplexes in a cellular or noncellular environment, a reliable sequence-based prediction of their three-dimensional fold would be extremely useful, yet is often limited by their remarkable structural diversity. A G-rich sequence related to a promoter sequence of the PDGFR-β nuclease hypersensitivity element (NHE) comprises a G3-G3-G2-G4-G3 pattern of five G-runs with two to four G residues. Although the predominant formation of three-layered canonical G-quadruplexes with uninterrupted G-columns can be expected, minimal base substitutions in a non-G-tract domain were shown to guide folding into either a basket-type antiparallel quadruplex, a parallel-stranded quadruplex with an interrupted G-column, a quadruplex with a V-shaped loop, or a (3+1) hybrid quadruplex. A 3D NMR structure for each of the different folds was determined. Supported by thermodynamic profiling on additional sequence variants, formed topologies were rationalized by the identification and assessment of specific critical interactions of loop and overhang residues, giving valuable insights into their contribution to favor a particular conformer. The variability of such tertiary interactions, together with only small differences in quadruplex free energies, emphasizes current limits for a reliable sequence-dependent prediction of favored topologies from sequences with multiple irregularly positioned G-tracts.
Collapse
Affiliation(s)
- Yoanes Maria Vianney
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff Str. 4, D-17489 Greifswald, Germany
| | - Nina Schröder
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff Str. 4, D-17489 Greifswald, Germany
| | - Jagannath Jana
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff Str. 4, D-17489 Greifswald, Germany
| | - Gregor Chojetzki
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff Str. 4, D-17489 Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff Str. 4, D-17489 Greifswald, Germany
| |
Collapse
|
14
|
Stitch M, Avagliano D, Graczyk D, Clark IP, González L, Towrie M, Quinn SJ. Good Vibrations Report on the DNA Quadruplex Binding of an Excited State Amplified Ruthenium Polypyridyl IR Probe. J Am Chem Soc 2023; 145:21344-21360. [PMID: 37736878 PMCID: PMC10557146 DOI: 10.1021/jacs.3c06099] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Indexed: 09/23/2023]
Abstract
The nitrile containing Ru(II)polypyridyl complex [Ru(phen)2(11,12-dCN-dppz)]2+ (1) is shown to act as a sensitive infrared probe of G-quadruplex (G4) structures. UV-visible absorption spectroscopy reveals enantiomer sensitive binding for the hybrid htel(K) and antiparallel htel(Na) G4s formed by the human telomer sequence d[AG3(TTAG3)3]. Time-resolved infrared (TRIR) of 1 upon 400 nm excitation indicates dominant interactions with the guanine bases in the case of Λ-1/htel(K), Δ-1/htel(K), and Λ-1/htel(Na) binding, whereas Δ-1/htel(Na) binding is associated with interactions with thymine and adenine bases in the loop. The intense nitrile transient at 2232 cm-1 undergoes a linear shift to lower frequency as the solution hydrogen bonding environment decreases in DMSO/water mixtures. This shift is used as a sensitive reporter of the nitrile environment within the binding pocket. The lifetime of 1 in D2O (ca. 100 ps) is found to increase upon DNA binding, and monitoring of the nitrile and ligand transients as well as the diagnostic DNA bleach bands shows that this increase is related to greater protection from the solvent environment. Molecular dynamics simulations together with binding energy calculations identify the most favorable binding site for each system, which are in excellent agreement with the observed TRIR solution study. This study shows the power of combining the environmental sensitivity of an infrared (IR) probe in its excited state with the TRIR DNA "site effect" to gain important information about the binding site of photoactive agents and points to the potential of such amplified IR probes as sensitive reporters of biological environments.
Collapse
Affiliation(s)
- Mark Stitch
- School
of Chemistry, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Davide Avagliano
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währingerstr. 19, 1090 Vienna, Austria
- Department
of Chemistry, Chemical Physics Theory Group, University of Toronto, 80 St. George St., Toronto, Ontario M5S 3H6, Canada
| | - Daniel Graczyk
- School
of Chemistry, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Ian P. Clark
- Central
Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, U.K.
| | - Leticia González
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währingerstr. 19, 1090 Vienna, Austria
- Vienna
Research Platform on Accelerating Photoreaction Discovery, University of Vienna, Währingerstr. 19, 1090 Vienna, Austria
| | - Michael Towrie
- Central
Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, U.K.
| | - Susan J Quinn
- School
of Chemistry, University College Dublin, Dublin, D04 V1W8, Ireland
| |
Collapse
|
15
|
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.
Collapse
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.)
| |
Collapse
|
16
|
Stadlbauer P, Mlýnský V, Krepl M, Šponer J. Complexity of Guanine Quadruplex Unfolding Pathways Revealed by Atomistic Pulling Simulations. J Chem Inf Model 2023; 63:4716-4731. [PMID: 37458574 PMCID: PMC10428220 DOI: 10.1021/acs.jcim.3c00171] [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: 02/02/2023] [Indexed: 08/15/2023]
Abstract
Guanine quadruplexes (GQs) are non-canonical nucleic acid structures involved in many biological processes. GQs formed in single-stranded regions often need to be unwound by cellular machinery, so their mechanochemical properties are important. Here, we performed steered molecular dynamics simulations of human telomeric GQs to study their unfolding. We examined four pulling regimes, including a very slow setup with pulling velocity and force load accessible to high-speed atomic force microscopy. We identified multiple factors affecting the unfolding mechanism, i.e.,: (i) the more the direction of force was perpendicular to the GQ channel axis (determined by GQ topology), the more the base unzipping mechanism happened, (ii) the more parallel the direction of force was, GQ opening and cross-like GQs were more likely to occur, (iii) strand slippage mechanism was possible for GQs with an all-anti pattern in a strand, and (iv) slower pulling velocity led to richer structural dynamics with sampling of more intermediates and partial refolding events. We also identified that a GQ may eventually unfold after a force drop under forces smaller than those that the GQ withstood before the drop. Finally, we found out that different unfolding intermediates could have very similar chain end-to-end distances, which reveals some limitations of structural interpretations of single-molecule spectroscopic data.
Collapse
Affiliation(s)
- Petr Stadlbauer
- Institute of Biophysics of the Czech
Academy of Sciences, Královopolská 135, Brno 612 00, Czech Republic
| | - Vojtěch Mlýnský
- Institute of Biophysics of the Czech
Academy of Sciences, Královopolská 135, Brno 612 00, Czech Republic
| | - Miroslav Krepl
- Institute of Biophysics of the Czech
Academy of Sciences, Královopolská 135, Brno 612 00, Czech Republic
| | - Jiří Šponer
- Institute of Biophysics of the Czech
Academy of Sciences, Královopolská 135, Brno 612 00, Czech Republic
| |
Collapse
|
17
|
Libera V, Ripanti F, Petrillo C, Sacchetti F, Ramos-Soriano J, Galan MC, Schirò G, Paciaroni A, Comez L. Stability of Human Telomeric G-Quadruplexes Complexed with Photosensitive Ligands and Irradiated with Visible Light. Int J Mol Sci 2023; 24:ijms24109090. [PMID: 37240437 DOI: 10.3390/ijms24109090] [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: 04/26/2023] [Revised: 05/16/2023] [Accepted: 05/19/2023] [Indexed: 05/28/2023] Open
Abstract
Guanine-rich DNA sequences can fold into non-canonical nucleic acid structures called G-quadruplexes (G4s). These nanostructures have strong implications in many fields, from medical science to bottom-up nanotechnologies. As a result, ligands interacting with G4s have attracted great attention as candidates in medical therapies, molecular probe applications, and biosensing. In recent years, the use of G4-ligand complexes as photopharmacological targets has shown significant promise for developing novel therapeutic strategies and nanodevices. Here, we studied the possibility of manipulating the secondary structure of a human telomeric G4 sequence through the interaction with two photosensitive ligands, DTE and TMPyP4, whose response to visible light is different. The effect of these two ligands on G4 thermal unfolding was also considered, revealing the occurrence of peculiar multi-step melting pathways and the different attitudes of the two molecules on the quadruplex stabilization.
Collapse
Affiliation(s)
- Valeria Libera
- Department of Physics and Geology, University of Perugia, Via Alessandro Pascoli, 06123 Perugia, Italy
- Istituto Officina dei Materiali-IOM, National Research Council-CNR, Via Alessandro Pascoli, 06123 Perugia, Italy
| | - Francesca Ripanti
- Department of Physics and Geology, University of Perugia, Via Alessandro Pascoli, 06123 Perugia, Italy
| | - Caterina Petrillo
- Department of Physics and Geology, University of Perugia, Via Alessandro Pascoli, 06123 Perugia, Italy
| | - Francesco Sacchetti
- Department of Physics and Geology, University of Perugia, Via Alessandro Pascoli, 06123 Perugia, Italy
| | - Javier Ramos-Soriano
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
| | - Maria Carmen Galan
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
| | - Giorgio Schirò
- CNRS, CEA, IBS, c/o University Grenoble Alpes, 38400 Grenoble, France
| | - Alessandro Paciaroni
- Department of Physics and Geology, University of Perugia, Via Alessandro Pascoli, 06123 Perugia, Italy
| | - Lucia Comez
- Istituto Officina dei Materiali-IOM, National Research Council-CNR, Via Alessandro Pascoli, 06123 Perugia, Italy
| |
Collapse
|
18
|
Jin B, Guo Z, Chen Z, Chen H, Li S, Deng Y, Jin L, Liu Y, Zhang Y, He N. Aptamers in cancer therapy: problems and new breakthroughs. J Mater Chem B 2023; 11:1609-1627. [PMID: 36744587 DOI: 10.1039/d2tb02579e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Aptamers, a class of oligonucleotides that can bind with molecular targets with high affinity and specificity, have been widely applied in research fields including biosensing, imaging, diagnosing, and therapy of diseases. However, compared with the rapid development in the research fields, the clinical application of aptamers is progressing at a much slower speed, especially in the therapy of cancer. Obstructions including nuclease degradation, renal clearance, a complex selection process, and potential side effects have inhibited the clinical transformation of aptamer-conjugated drugs. To overcome these problems, taking certain measures to improve the biocompatibility and stability of aptamer-conjugated drugs in vivo is necessary. In this review, the obstructions mentioned above are thoroughly discussed and the methods to overcome these problems are introduced in detail. Furthermore, landmark research works and the most recent studies on aptamer-conjugated drugs for cancer therapy are also listed as examples, and the future directions of research for aptamer clinical transformation are discussed.
Collapse
Affiliation(s)
- Baijiang Jin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China.
| | - Zhukang Guo
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China.
| | - Zhu Chen
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, Hunan, China
| | - Hui Chen
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, Hunan, China
| | - Song Li
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, Hunan, China
| | - Yan Deng
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, Hunan, China
| | - Lian Jin
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, Hunan, China
| | - Yuan Liu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China.
| | - Yuanying Zhang
- Department of Molecular Biology, Jiangsu Cancer Hospital, Nanjing 210009, P. R. China
| | - Nongyue He
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. .,Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, Hunan, China
| |
Collapse
|
19
|
The effect of side chain variations on quinazoline-pyrimidine G-quadruplex DNA ligands. Eur J Med Chem 2023; 248:115103. [PMID: 36645982 DOI: 10.1016/j.ejmech.2023.115103] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 01/05/2023] [Accepted: 01/06/2023] [Indexed: 01/09/2023]
Abstract
G-quadruplex (G4) DNA structures are involved in central biological processes such as DNA replication and transcription. These DNA structures are enriched in promotor regions of oncogenes and are thus promising as novel gene silencing therapeutic targets that can be used to regulate expression of oncoproteins and in particular those that has proven hard to drug with conventional strategies. G4 DNA structures in general have a well-defined and hydrophobic binding area that also is very flat and featureless and there are ample examples of G4 ligands but their further progression towards drug development is limited. In this study, we use synthetic organic chemistry to equip a drug-like and low molecular weight central fragment with different side chains and evaluate how this affect the compound's selectivity and ability to bind and stabilize G4 DNA. Furthermore, we study the binding interactions of the compounds and connect the experimental observations with the compound's structural conformations and electrostatic potentials to understand the basis for the observed improvements. Finally, we evaluate the top candidates' ability to selectively reduce cancer cell growth in a 3D co-culture model of pancreatic cancer which show that this is a powerful approach to generate highly active and selective low molecular weight G4 ligands with a promising therapeutic window.
Collapse
|
20
|
Evans L, Kotar A, Valentini M, Filloux A, Jamshidi S, Plavec J, Rahman KM, Vilar R. Identification and characterisation of G-quadruplex DNA-forming sequences in the Pseudomonas aeruginosa genome. RSC Chem Biol 2023; 4:94-100. [PMID: 36685252 PMCID: PMC9811510 DOI: 10.1039/d2cb00205a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 11/13/2022] [Indexed: 11/16/2022] Open
Abstract
A number of Gram-negative bacteria such as Pseudomonas aeruginosa are becoming resistant to front-line antibiotics. Consequently, there is a pressing need to find alternative bio-molecular targets for the development of new drugs. Since non-canonical DNA structures such as guanine-quadruplexes (G4s) have been implicated in regulating transcription, we were interested in determining whether there are putative quadruplex-forming sequences (PQS) in the genome of Pseudomonas aeruginosa. Using bioinformatic tools, we screened 36 genes potentially relevant to drug resistance for the presence of PQS and 10 of these were selected for biophysical characterisation (i.e. circular dichroism and thermal difference UV/Vis spectroscopy). These studies showed that three of these G-rich sequences (linked to murE, ftsB and mexC genes) form stable guanine-quadruplexes which were studied by NMR spectroscopy; detailed analysis of one of the sequences (mexC) confirmed that it adopts a two-quartet antiparallel quadruplex structure in the presence of K+ ions. We also show by FRET melting assays that small molecules can stabilise these three new G4 DNA structures under physiological conditions. These initial results could be of future interest in the development of new antibiotics with alternative bio-molecular targets which in turn would help tackle antimicrobial resistance.
Collapse
Affiliation(s)
- Lindsay Evans
- Department of Chemistry, Imperial College London, White City CampusLondon W12 OBZUK
| | - Anita Kotar
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 191000 LjubljanaSlovenia
| | - Martina Valentini
- Department of Life Sciences, MRC Centre for Molecular Microbiology and Infection, Imperial College London, South Kensington CampusLondon SW7 2AZUK
| | - Alain Filloux
- Department of Life Sciences, MRC Centre for Molecular Microbiology and Infection, Imperial College London, South Kensington CampusLondon SW7 2AZUK
| | - Shirin Jamshidi
- Institute of Pharmaceutical Science, King's College London, Franklin-Wilkins Building150 Stamford StreetLondon SE1 9NHUK
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 191000 LjubljanaSlovenia
| | - Khondaker Miraz Rahman
- Institute of Pharmaceutical Science, King's College London, Franklin-Wilkins Building150 Stamford StreetLondon SE1 9NHUK
| | - Ramon Vilar
- Department of Chemistry, Imperial College London, White City CampusLondon W12 OBZUK
| |
Collapse
|
21
|
Nandi S, Coane C, Villegas AE, Ray A, Di Felice R. The impact of G-quadruplex dynamics on inter-tetrad electronic couplings: a hybrid computational study. Phys Chem Chem Phys 2022; 24:22513-22522. [PMID: 36106845 DOI: 10.1039/d2cp03505g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The G-quadruplex is a fascinating nucleic acid motif with implications in biology, medicine, and nanotechnologies. G-quadruplexes can form in the telomeres at the edges of chromosomes and in other guanine-rich regions of the genome. They can also be engineered for exploitation as biological materials for nanodevices. Their higher stiffness and higher charge transfer rates make them better candidates in nanodevices than duplex DNA. For the development of molecular nanowires, it is important to optimize electron transport along the wire axis. One powerful basis to do so is by manipulating the structure, based on known effects that structural changes have on electron transport. Here, we investigate such effects, by a combination of classical simulations of the structure and dynamics and quantum calculations of electronic couplings. We find that this structure-function relationship is complex. A single helix shape parameter alone does not embody such complexity, but rather a combination of distances and angles between stacked bases influences charge transfer efficiency. By analyzing linear combinations of shape descriptors for different topologies, we identify the structural features that most affect charge transfer efficiency. We discuss the transferability of the proposed model and the limiting effects of inherent flexibility.
Collapse
Affiliation(s)
- Samprita Nandi
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089, USA.
| | - Colin Coane
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089, USA.
| | - Angel-Emilio Villegas
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089, USA.
| | - Angana Ray
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089, USA.
| | - Rosa Di Felice
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089, USA. .,Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA.,CNR Institute of Nanoscience, 41125 Modena, Italy
| |
Collapse
|
22
|
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.
Collapse
|
23
|
Jana J, Vianney YM, Schröder N, Weisz K. Guiding the folding of G-quadruplexes through loop residue interactions. Nucleic Acids Res 2022; 50:7161-7175. [PMID: 35758626 PMCID: PMC9262619 DOI: 10.1093/nar/gkac549] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/25/2022] [Accepted: 06/14/2022] [Indexed: 12/24/2022] Open
Abstract
A G-rich sequence was designed to allow folding into either a stable parallel or hybrid-type topology. With the parent sequence featuring coexisting species, various related sequences with single and double mutations and with a shortened central propeller loop affected the topological equilibrium. Two simple modifications, likewise introduced separately to all sequences, were employed to lock folds into one of the topologies without noticeable structural alterations. The unique combination of sequence mutations, high-resolution NMR structural information, and the thermodynamic stability for both topological competitors identified critical loop residue interactions. In contrast to first loop residues, which are mostly disordered and exposed to solvent in both propeller and lateral loops bridging a narrow groove, the last loop residue in a lateral three-nucleotide loop is engaged in stabilizing stacking interactions. The propensity of single-nucleotide loops to favor all-parallel topologies by enforcing a propeller-like conformation of an additional longer loop is shown to result from their preference in linking two outer tetrads of the same tetrad polarity. Taken together, the present studies contribute to a better structural and thermodynamic understanding of delicate loop interactions in genomic and artificially designed quadruplexes, e.g. when employed as therapeutics or in other biotechnological applications.
Collapse
Affiliation(s)
- Jagannath Jana
- Institute of Biochemistry, Universität Greifswald, D-17489 Greifswald, Germany
| | | | - Nina Schröder
- Institute of Biochemistry, Universität Greifswald, D-17489 Greifswald, Germany
| | - Klaus Weisz
- To whom correspondence should be addressed. Tel: +49 3834 420 4426; Fax: +49 3834 420 4427;
| |
Collapse
|
24
|
Libera V, Bianchi F, Rossi B, D’Amico F, Masciovecchio C, Petrillo C, Sacchetti F, Paciaroni A, Comez L. Solvent Vibrations as a Proxy of the Telomere G-Quadruplex Rearrangements across Thermal Unfolding. Int J Mol Sci 2022; 23:ijms23095123. [PMID: 35563512 PMCID: PMC9100830 DOI: 10.3390/ijms23095123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 11/16/2022] Open
Abstract
G-quadruplexes (G4s) are noncanonical forms of DNA involved in many key genome functions. Here, we exploited UV Resonance Raman scattering to simultaneously explore the vibrational behavior of a human telomeric G4 (Tel22) and its aqueous solvent as the biomolecule underwent thermal melting. We found that the OH stretching band, related to the local hydrogen-bonded network of a water molecule, was in strict relation with the vibrational features of the G4 structure as a function of temperature. In particular, the modifications to the tetrahedral ordering of the water network were strongly coupled to the DNA rearrangements, showing changes in temperature that mirrored the multi-step melting process of Tel22. The comparison between circular dichroism and Raman results supported this view. The present findings provide novel insights into the impact of the molecular environment on G4 conformation. Improving current knowledge on the solvent structural properties will also contribute to a better understanding of the role played by water arrangement in the complexation of G4s with ligands.
Collapse
Affiliation(s)
- Valeria Libera
- Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, 06123 Perugia, Italy; (V.L.); (F.B.); (C.P.); (F.S.)
- IOM-CNR c/o Department of Physics and Geology, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Federico Bianchi
- Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, 06123 Perugia, Italy; (V.L.); (F.B.); (C.P.); (F.S.)
| | - Barbara Rossi
- Elettra Sincrotrone Trieste, S.S. 14 Km 163.5, 34012 Trieste, Italy; (B.R.); (F.D.); (C.M.)
| | - Francesco D’Amico
- Elettra Sincrotrone Trieste, S.S. 14 Km 163.5, 34012 Trieste, Italy; (B.R.); (F.D.); (C.M.)
| | - Claudio Masciovecchio
- Elettra Sincrotrone Trieste, S.S. 14 Km 163.5, 34012 Trieste, Italy; (B.R.); (F.D.); (C.M.)
| | - Caterina Petrillo
- Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, 06123 Perugia, Italy; (V.L.); (F.B.); (C.P.); (F.S.)
| | - Francesco Sacchetti
- Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, 06123 Perugia, Italy; (V.L.); (F.B.); (C.P.); (F.S.)
| | - Alessandro Paciaroni
- Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, 06123 Perugia, Italy; (V.L.); (F.B.); (C.P.); (F.S.)
- Correspondence: (A.P.); (L.C.)
| | - Lucia Comez
- IOM-CNR c/o Department of Physics and Geology, Università degli Studi di Perugia, 06123 Perugia, Italy
- Correspondence: (A.P.); (L.C.)
| |
Collapse
|
25
|
Galindo-Murillo R, Winkler L, Ma J, Hanelli F, Fleming AM, Burrows CJ, Cheatham TE. Riboflavin Stabilizes Abasic, Oxidized G-Quadruplex Structures. Biochemistry 2022; 61:265-275. [PMID: 35104101 PMCID: PMC8851688 DOI: 10.1021/acs.biochem.1c00598] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
![]()
The G-quadruplex
is a noncanonical fold of DNA commonly found at
telomeres and within gene promoter regions of the genome. These guanine-rich
sequences are highly susceptible to damages such as base oxidation
and depurination, leading to abasic sites. In the present work, we
address whether a vacancy, such as an abasic site, in a G-quadruplex
serves as a specific ligand recognition site. When the G-tetrad is
all guanines, the vacant (abasic) site is recognized and bound by
free guanine nucleobase. However, we aim to understand whether the
preference for a specific ligand recognition changes with the presence
of a guanine oxidation product 8-oxo-7,8-dihydroguanine (OG) adjacent
to the vacancy in the tetrad. Using molecular dynamics simulation,
circular dichroism, and nuclear magnetic resonance, we examined the
ability for riboflavin to stabilize abasic site-containing G-quadruplex
structures. Through structural and free energy binding analysis, we
observe riboflavin’s ability to stabilize an abasic site-containing
G-quadruplex only in the presence of an adjacent OG-modified base.
Further, when compared to simulation with the vacancy filled by free
guanine, we observe that the free guanine nucleobase is pushed outside
of the tetrad by OG to interact with other parts of the structure,
including loop residues. These results support the preference of riboflavin
over free guanine to fill an OG-adjacent G-quadruplex abasic vacancy.
Collapse
Affiliation(s)
- Rodrigo Galindo-Murillo
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, 2000 East 30 South Skaggs 306, Salt Lake City, Utah 84112, United States
| | - Lauren Winkler
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, 2000 East 30 South Skaggs 306, Salt Lake City, Utah 84112, United States
| | - Jingwei Ma
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
| | - Fatjon Hanelli
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
| | - Aaron M Fleming
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
| | - Cynthia J Burrows
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
| | - Thomas E Cheatham
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, 2000 East 30 South Skaggs 306, Salt Lake City, Utah 84112, United States
| |
Collapse
|
26
|
Zok T, Kraszewska N, Miskiewicz J, Pielacinska P, Zurkowski M, Szachniuk M. ONQUADRO: a database of experimentally determined quadruplex structures. Nucleic Acids Res 2022; 50:D253-D258. [PMID: 34986600 PMCID: PMC8728301 DOI: 10.1093/nar/gkab1118] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 10/22/2021] [Accepted: 10/25/2021] [Indexed: 01/02/2023] Open
Abstract
ONQUADRO is an advanced database system that supports the study of the structures of canonical and non-canonical quadruplexes. It combines a relational database that collects comprehensive information on tetrads, quadruplexes, and G4-helices; programs to compute structure parameters and visualise the data; scripts for statistical analysis; automatic updates and newsletter modules; and a web application that provides a user interface. The database is a self-updating resource, with new information arriving once a week. The preliminary data are downloaded from the Protein Data Bank, processed, annotated, and completed. As of August 2021, ONQUADRO contains 1,661 tetrads, 518 quadruplexes, and 30 G4-helices found in 467 experimentally determined 3D structures of nucleic acids. Users can view and download their description: sequence, secondary structure (dot-bracket, classical diagram, arc diagram), tertiary structure (ball-and-stick, surface or vdw-ball model, layer diagram), planarity, twist, rise, chi angle (value and type), loop characteristics, strand directionality, metal ions, ONZ, and Webba da Silva classification (the latter by loop topology and tetrad combination), origin structure ID, assembly ID, experimental method, and molecule type. The database is freely available at https://onquadro.cs.put.poznan.pl/. It can be used on both desktop computers and mobile devices.
Collapse
Affiliation(s)
- Tomasz Zok
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Natalia Kraszewska
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Joanna Miskiewicz
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Paulina Pielacinska
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Michal Zurkowski
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Marta Szachniuk
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| |
Collapse
|
27
|
Ravichandran S, Razzaq M, Parveen N, Ghosh A, Kim KK. The effect of hairpin loop on the structure and gene expression activity of the long-loop G-quadruplex. Nucleic Acids Res 2021; 49:10689-10706. [PMID: 34450640 PMCID: PMC8501965 DOI: 10.1093/nar/gkab739] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/10/2021] [Accepted: 08/24/2021] [Indexed: 12/29/2022] Open
Abstract
G-quadruplex (G4), a four-stranded DNA or RNA structure containing stacks of guanine tetrads, plays regulatory roles in many cellular functions. So far, conventional G4s containing loops of 1–7 nucleotides have been widely studied. Increasing experimental evidence suggests that unconventional G4s, such as G4s containing long loops (long-loop G4s), play a regulatory role in the genome by forming a stable structure. Other secondary structures such as hairpins in the loop might thus contribute to the stability of long-loop G4s. Therefore, investigation of the effect of the hairpin-loops on the structure and function of G4s is required. In this study, we performed a systematic biochemical investigation of model G4s containing long loops with various sizes and structures. We found that the long-loop G4s are less stable than conventional G4s, but their stability increased when the loop forms a hairpin (hairpin-G4). We also verified the biological significance of hairpin-G4s by showing that hairpin-G4s present in the genome also form stable G4s and regulate gene expression as confirmed by in cellulo reporter assays. This study contributes to expanding the scope and diversity of G4s, thus facilitating future studies on the role of G4s in the human genome.
Collapse
Affiliation(s)
- Subramaniyam Ravichandran
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Maria Razzaq
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Nazia Parveen
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Ambarnil Ghosh
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Kyeong Kyu Kim
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| |
Collapse
|
28
|
Jana J, Weisz K. Thermodynamic Stability of G-Quadruplexes: Impact of Sequence and Environment. Chembiochem 2021; 22:2848-2856. [PMID: 33844423 PMCID: PMC8518667 DOI: 10.1002/cbic.202100127] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/09/2021] [Indexed: 12/19/2022]
Abstract
G-quadruplexes have attracted growing interest in recent years due to their occurrence in vivo and their possible biological functions. In addition to being promising targets for drug design, these four-stranded nucleic acid structures have also been recognized as versatile tools for various technological applications. Whereas a large number of studies have yielded insight into their remarkable structural diversity, our current knowledge on G-quadruplex stabilities as a function of sequence and environmental factors only gradually emerges with an expanding collection of thermodynamic data. This minireview provides an overview of general rules that may be used to better evaluate quadruplex thermodynamic stabilities but also discusses present challenges in predicting most stable folds for a given sequence and environment.
Collapse
Affiliation(s)
- Jagannath Jana
- Institute of BiochemistryUniversität GreifswaldFelix-Hausdorff Str. 417489GreifswaldGermany
| | - Klaus Weisz
- Institute of BiochemistryUniversität GreifswaldFelix-Hausdorff Str. 417489GreifswaldGermany
| |
Collapse
|
29
|
Weisz K. A world beyond double-helical nucleic acids: the structural diversity of tetra-stranded G-quadruplexes. CHEMTEXTS 2021. [DOI: 10.1007/s40828-021-00150-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AbstractNucleic acids can adopt various secondary structures including double-, triple-, and tetra-stranded helices that differ by the specific hydrogen bond mediated pairing pattern between their nucleobase constituents. Whereas double-helical DNA relies on Watson–Crick base pairing to play a prominent role in storing genetic information, G-quadruplexes are tetra-stranded structures that are formed by the association of guanine bases from G-rich DNA and RNA sequences. During the last few decades, G-quadruplexes have attracted considerable interest after the realization that they form and exert regulatory functions in vivo. In addition, quadruplex architectures have also been recognized as versatile and powerful tools in a growing number of technological applications. To appreciate the astonishing structural diversity of these tetra-stranded structures and to give some insight into basic interactions that govern their folding, this article gives an overview of quadruplex structures and rules associated with the formation of different topologies. A brief discussion will also focus on nonconventional quadruplexes as well as on general principles when targeting quadruplexes with ligands.
Graphic abstract
Collapse
|
30
|
Zaccaria F, van der Lubbe SCC, Nieuwland C, Hamlin TA, Fonseca Guerra C. How Divalent Cations Interact with the Internal Channel Site of Guanine Quadruplexes. Chemphyschem 2021; 22:2286-2296. [PMID: 34435425 PMCID: PMC9293024 DOI: 10.1002/cphc.202100529] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/24/2021] [Indexed: 11/06/2022]
Abstract
The formation of guanine quadruplexes (GQ) in DNA is crucial in telomere homeostasis and regulation of gene expression. Pollution metals can interfere with these DNA superstructures upon coordination. In this work, we study the affinity of the internal GQ channel site towards alkaline earth metal (Mg2+, Ca2+, Sr2+, and Ba2+), and (post‐)transition metal (Zn2+, Cd2+, Hg2+, and Pb2+) cations using density functional theory computations. We find that divalent cations generally bind to the GQ cavity with a higher affinity than conventional monovalent cations (e. g. K+). Importantly, we establish the nature of the cation‐GQ interaction and highlight the relationship between ionic and nuclear charge, and the electrostatic and covalent interactions. The covalent interaction strength plays an important role in the cation affinity and can be traced back to the relative stabilization of cations’ unoccupied atomic orbitals. Overall, our findings contribute to a deeper understanding of how pollution metals could induce genomic instability.
Collapse
Affiliation(s)
- Francesco Zaccaria
- Department of Theoretical Chemistry and, Amsterdam Center for Multiscale Modelling, AIMMS, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Stephanie C C van der Lubbe
- Department of Theoretical Chemistry and, Amsterdam Center for Multiscale Modelling, AIMMS, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Celine Nieuwland
- Department of Theoretical Chemistry and, Amsterdam Center for Multiscale Modelling, AIMMS, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Trevor A Hamlin
- Department of Theoretical Chemistry and, Amsterdam Center for Multiscale Modelling, AIMMS, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Célia Fonseca Guerra
- Department of Theoretical Chemistry and, Amsterdam Center for Multiscale Modelling, AIMMS, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands.,Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| |
Collapse
|
31
|
Mohr S, Jana J, Vianney YM, Weisz K. Expanding the Topological Landscape by a G-Column Flip of a Parallel G-Quadruplex. Chemistry 2021; 27:10437-10447. [PMID: 33955615 PMCID: PMC8361731 DOI: 10.1002/chem.202101181] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Indexed: 01/14/2023]
Abstract
Canonical G‐quadruplexes can adopt a variety of different topologies depending on the arrangement of propeller, lateral, or diagonal loops connecting the four G‐columns. A novel intramolecular G‐quadruplex structure is derived through inversion of the last G‐tract of a three‐layered parallel fold, associated with the transition of a single propeller into a lateral loop. The resulting (3+1) hybrid fold features three syn⋅anti⋅anti⋅anti G‐tetrads with a 3’‐terminal all‐syn G‐column. Although the ability of forming a duplex stem‐loop between G‐tracts seems beneficial for a propeller‐to‐lateral loop rearrangement, unmodified G‐rich sequences resist folding into the new (3+1) topology. However, refolding can be driven by the incorporation of syn‐favoring guanosine analogues into positions of the fourth G‐stretch. The presented hybrid‐type G‐quadruplex structure as determined by NMR spectroscopy may provide for an additional scaffold in quadruplex‐based technologies.
Collapse
Affiliation(s)
- Swantje Mohr
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Jagannath Jana
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Yoanes Maria Vianney
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| |
Collapse
|
32
|
Wang E, Thombre R, Shah Y, Latanich R, Wang J. G-Quadruplexes as pathogenic drivers in neurodegenerative disorders. Nucleic Acids Res 2021; 49:4816-4830. [PMID: 33784396 PMCID: PMC8136783 DOI: 10.1093/nar/gkab164] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 02/20/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022] Open
Abstract
G-quadruplexes (G4s), higher-order DNA and RNA secondary structures featuring guanine-rich nucleic acid sequences with various conformations, are widely distributed in the human genome. These structural motifs are known to participate in basic cellular processes, including transcription, splicing, and translation, and their functions related to health and disease are becoming increasingly recognized. In this review, we summarize the landscape of G4s involved in major neurodegenerative disorders, describing the genes that contain G4-forming sequences and proteins that have high affinity for G4-containing elements. The functions of G4s are diverse, with potentially protective or deleterious effects in the pathogenic cascades of various neurological diseases. While the studies of the functions of G4s in vivo, including those involved in pathophysiology, are still in their early stages, we will nevertheless discuss the evidence pointing to their biological relevance. A better understanding of this unique structural element in the biological context is important for unveiling its potential roles in the pathogenesis of diseases such as neurodegeneration and for designing new diagnostic and therapeutic strategies.
Collapse
Affiliation(s)
- Ernest Wang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore MD, 21205, USA.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Ravi Thombre
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore MD, 21205, USA.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Yajas Shah
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore MD, 21205, USA.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Rachel Latanich
- Department of Medicine, Division of Gastroenterology and Hepatology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Jiou Wang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore MD, 21205, USA.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| |
Collapse
|
33
|
Jana J, Mohr S, Vianney YM, Weisz K. Structural motifs and intramolecular interactions in non-canonical G-quadruplexes. RSC Chem Biol 2021; 2:338-353. [PMID: 34458788 PMCID: PMC8341446 DOI: 10.1039/d0cb00211a] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/14/2021] [Indexed: 12/12/2022] Open
Abstract
Guanine(G)-rich DNA or RNA sequences can assemble or intramolecularly fold into G-quadruplexes formed through the stacking of planar G·G·G·G tetrads in the presence of monovalent cations. These secondary nucleic acid structures have convincingly been shown to also exist within a cellular environment exerting important regulatory functions in physiological processes. For identifying nucleic acid segments prone to quadruplex formation, a putative quadruplex sequence motif encompassing closely spaced tracts of three or more guanosines is frequently employed for bioinformatic search algorithms. Depending on the number and type of intervening residues as well as on solution conditions, such sequences may fold into various canonical G4 topologies with continuous G-columns. On the other hand, a growing number of sequences capable of quadruplex formation feature G-deficient guanine tracts, escaping the conservative consensus motif. By folding into non-canonical quadruplex structures, they adopt unique topologies depending on their specific sequence context. These include G-columns with only two guanines, bulges, snapback loops, D- and V-shaped loops as well as interlocked structures. This review focuses on G-quadruplex species carrying such distinct structural motifs. It evaluates characteristic features of their non-conventional scaffold and highlights principles of stabilizing interactions that also allow for their folding into stable G-quadruplex structures.
Collapse
Affiliation(s)
- Jagannath Jana
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
| | - Swantje Mohr
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
| | - Yoanes Maria Vianney
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
| | - Klaus Weisz
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
| |
Collapse
|
34
|
Beyond the double helix: DNA structural diversity and the PDB. J Biol Chem 2021; 296:100553. [PMID: 33744292 PMCID: PMC8063756 DOI: 10.1016/j.jbc.2021.100553] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/15/2021] [Accepted: 03/16/2021] [Indexed: 12/11/2022] Open
Abstract
The determination of the double helical structure of DNA in 1953 remains the landmark event in the development of modern biological and biomedical science. This structure has also been the starting point for the determination of some 2000 DNA crystal structures in the subsequent 68 years. Their structural diversity has extended to the demonstration of sequence-dependent local structure in duplex DNA, to DNA bending in short and long sequences and in the DNA wound round the nucleosome, and to left-handed duplex DNAs. Beyond the double helix itself, in circumstances where DNA sequences are or can be induced to unwind from being duplex, a wide variety of topologies and forms can exist. Quadruplex structures, based on four-stranded cores of stacked G-quartets, are prevalent though not randomly distributed in the human and other genomes and can play roles in transcription, translation, and replication. Yet more complex folds can result in DNAs with extended tertiary structures and enzymatic/catalytic activity. The Protein Data Bank is the depository of all these structures, and the resource where structures can be critically examined and validated, as well as compared one with another to facilitate analysis of conformational and base morphology features. This review will briefly survey the major structural classes of DNAs and illustrate their significance, together with some examples of how the use of the Protein Data Bank by for example, data mining, has illuminated DNA structural concepts.
Collapse
|
35
|
Jing H, Fu W, Hu W, Xu S, Xu X, He M, Liu Y, Zhang N. NMR structural study on the self-trimerization of d(GTTAGG) into a dynamic trimolecular G-quadruplex assembly preferentially in Na+ solution with a moderate K+ tolerance. Nucleic Acids Res 2021; 49:2306-2316. [PMID: 33524157 PMCID: PMC7913680 DOI: 10.1093/nar/gkab028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 01/05/2021] [Accepted: 01/15/2021] [Indexed: 12/12/2022] Open
Abstract
Vast G-quadruplexes (GQs) are primarily folded by one, two, or four G-rich oligomers, rarely with an exception. Here, we present the first NMR solution structure of a trimolecular GQ (tri-GQ) that is solely assembled by the self-trimerization of d(GTTAGG), preferentially in Na+ solution tolerant to an equal amount of K+ cation. Eight guanines from three asymmetrically folded strands of d(GTTAGG) are organized into a two-tetrad core, which features a broken G-column and two width-irregular grooves. Fast strand exchanges on a timescale of second at 17°C spontaneously occur between folded tri-GQ and unfolded single-strand of d(GTTAGG) that both species coexist in dynamic equilibrium. Thus, this tri-GQ is not just simply a static assembly but rather a dynamic assembly. Moreover, another minor tetra-GQ that has putatively tetrameric (2+2) antiparallel topology becomes noticeable only at an extremely high strand concentration above 18 mM. The major tri-GQ and minor tetra-GQ are considered to be mutually related, and their reversible interconversion pathways are proposed accordingly. The sequence d(GTTAGG) could be regarded as either a reading frame shifted single repeat of human telomeric DNA or a 1.5 repeat of Bombyx mori telomeric DNA. Overall, our findings provide new insight into GQs and expect more functional applications.
Collapse
Affiliation(s)
- Haitao Jing
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Wenqiang Fu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Wenxuan Hu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Suping Xu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
| | - Xiaojuan Xu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Miao He
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Yangzhong Liu
- University of Science and Technology of China, Hefei 230026, China
| | - Na Zhang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.,Key Laboratory of Anhui Province for High Field Magnetic Resonance Imaging, Hefei 230031, China.,High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
| |
Collapse
|
36
|
Volek M, Kolesnikova S, Svehlova K, Srb P, Sgallová R, Streckerová T, Redondo JA, Veverka V, Curtis EA. Overlapping but distinct: a new model for G-quadruplex biochemical specificity. Nucleic Acids Res 2021; 49:1816-1827. [PMID: 33544841 PMCID: PMC7913677 DOI: 10.1093/nar/gkab037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 01/09/2021] [Accepted: 01/18/2021] [Indexed: 11/29/2022] Open
Abstract
G-quadruplexes are noncanonical nucleic acid structures formed by stacked guanine tetrads. They are capable of a range of functions and thought to play widespread biological roles. This diversity raises an important question: what determines the biochemical specificity of G-quadruplex structures? The answer is particularly important from the perspective of biological regulation because genomes can contain hundreds of thousands of G-quadruplexes with a range of functions. Here we analyze the specificity of each sequence in a 496-member library of variants of a reference G-quadruplex with respect to five functions. Our analysis shows that the sequence requirements of G-quadruplexes with these functions are different from one another, with some mutations altering biochemical specificity by orders of magnitude. Mutations in tetrads have larger effects than mutations in loops, and changes in specificity are correlated with changes in multimeric state. To complement our biochemical data we determined the solution structure of a monomeric G-quadruplex from the library. The stacked and accessible tetrads rationalize why monomers tend to promote a model peroxidase reaction and generate fluorescence. Our experiments support a model in which the sequence requirements of G-quadruplexes with different functions are overlapping but distinct. This has implications for biological regulation, bioinformatics, and drug design.
Collapse
Affiliation(s)
- Martin Volek
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic.,Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Prague 128 44, Czech Republic
| | - Sofia Kolesnikova
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic.,Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague 166 28, Czech Republic
| | - Katerina Svehlova
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic.,Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Prague 128 44, Czech Republic
| | - Pavel Srb
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| | - Ráchel Sgallová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic.,Department of Low-Temperature Physics, Faculty of Mathematics and Physics, Charles University in Prague, Prague 180 00, Czech Republic
| | - Tereza Streckerová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic.,Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague 166 28, Czech Republic
| | - Juan A Redondo
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| | - Václav Veverka
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic.,Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague 128 44, Czech Republic
| | - Edward A Curtis
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| |
Collapse
|
37
|
Ghosh A, Largy E, Gabelica V. DNA G-quadruplexes for native mass spectrometry in potassium: a database of validated structures in electrospray-compatible conditions. Nucleic Acids Res 2021; 49:2333-2345. [PMID: 33555347 PMCID: PMC7913678 DOI: 10.1093/nar/gkab039] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 12/22/2020] [Accepted: 01/19/2021] [Indexed: 02/07/2023] Open
Abstract
G-quadruplex DNA structures have become attractive drug targets, and native mass spectrometry can provide detailed characterization of drug binding stoichiometry and affinity, potentially at high throughput. However, the G-quadruplex DNA polymorphism poses problems for interpreting ligand screening assays. In order to establish standardized MS-based screening assays, we studied 28 sequences with documented NMR structures in (usually ∼100 mM) potassium, and report here their circular dichroism (CD), melting temperature (Tm), NMR spectra and electrospray mass spectra in 1 mM KCl/100 mM trimethylammonium acetate. Based on these results, we make a short-list of sequences that adopt the same structure in the MS assay as reported by NMR, and provide recommendations on using them for MS-based assays. We also built an R-based open-source application to build and consult a database, wherein further sequences can be incorporated in the future. The application handles automatically most of the data processing, and allows generating custom figures and reports. The database is included in the g4dbr package (https://github.com/EricLarG4/g4dbr) and can be explored online (https://ericlarg4.github.io/G4_database.html).
Collapse
Affiliation(s)
- Anirban Ghosh
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33000 Bordeaux, France
| | - Eric Largy
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33000 Bordeaux, France
| | - Valérie Gabelica
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33000 Bordeaux, France
| |
Collapse
|
38
|
Stadlbauer P, Islam B, Otyepka M, Chen J, Monchaud D, Zhou J, Mergny JL, Šponer J. Insights into G-Quadruplex-Hemin Dynamics Using Atomistic Simulations: Implications for Reactivity and Folding. J Chem Theory Comput 2021; 17:1883-1899. [PMID: 33533244 DOI: 10.1021/acs.jctc.0c01176] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Guanine quadruplex nucleic acids (G4s) are involved in key biological processes such as replication or transcription. Beyond their biological relevance, G4s find applications as biotechnological tools since they readily bind hemin and enhance its peroxidase activity, creating a G4-DNAzyme. The biocatalytic properties of G4-DNAzymes have been thoroughly studied and used for biosensing purposes. Despite hundreds of applications and massive experimental efforts, the atomistic details of the reaction mechanism remain unclear. To help select between the different hypotheses currently under investigation, we use extended explicit-solvent molecular dynamics (MD) simulations to scrutinize the G4/hemin interaction. We find that besides the dominant conformation in which hemin is stacked atop the external G-quartets, hemin can also transiently bind to the loops and be brought to the external G-quartets through diverse delivery mechanisms. The simulations do not support the catalytic mechanism relying on a wobbling guanine. Similarly, the catalytic role of the iron-bound water molecule is not in line with our results; however, given the simulation limitations, this observation should be considered with some caution. The simulations rather suggest tentative mechanisms in which the external G-quartet itself could be responsible for the unique H2O2-promoted biocatalytic properties of the G4/hemin complexes. Once stacked atop a terminal G-quartet, hemin rotates about its vertical axis while readily sampling shifted geometries where the iron transiently contacts oxygen atoms of the adjacent G-quartet. This dynamics is not apparent from the ensemble-averaged structure. We also visualize transient interactions between the stacked hemin and the G4 loops. Finally, we investigated interactions between hemin and on-pathway folding intermediates of the parallel-stranded G4 fold. The simulations suggest that hemin drives the folding of parallel-stranded G4s from slip-stranded intermediates, acting as a G4 chaperone. Limitations of the MD technique are briefly discussed.
Collapse
Affiliation(s)
- Petr Stadlbauer
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Barira Islam
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Michal Otyepka
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic.,Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute, Palacký University, Křížkovského 8, 779 00 Olomouc, Czech Republic
| | - Jielin Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - David Monchaud
- Institut de Chimie Moléculaire (ICMUB), CNRS UMR6302, UBFC, Dijon 21078, France
| | - Jun Zhou
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jean-Louis Mergny
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic.,State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China.,Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128 Palaiseau cedex, France
| | - Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| |
Collapse
|
39
|
Devereux SJ, Poynton FE, Baptista FR, Gunnlaugsson T, Cardin CJ, Sazanovich IV, Towrie M, Kelly JM, Quinn SJ. Caught in the Loop: Binding of the [Ru(phen) 2 (dppz)] 2+ Light-Switch Compound to Quadruplex DNA in Solution Informed by Time-Resolved Infrared Spectroscopy. Chemistry 2020; 26:17103-17109. [PMID: 32725823 DOI: 10.1002/chem.202002165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Indexed: 01/05/2023]
Abstract
Ultrafast time-resolved infrared (TRIR) is used to report on the binding site of the [Ru(phen)2 (dppz)]2+ "light-switch" complex with both bimolecular (Oxytricha nova telomere) and intramolecular (human telomere) guanine-quadruplex structures in both K+ and Na+ containing solutions. TRIR permits the simultaneous monitoring both of the "dark" and "bright" states of the complex and of the quadruplex nucleobase bases, the latter via a Stark effect induced by the excited state of the complex. These data are used to establish the contribution of guanine base stacking and loop interactions to the binding site of this biologically relevant DNA structure in solution. A particularly striking observation is the strong thymine signal observed for the Na+ form of the human telomere sequence, which is expected to be in the anti-parallel conformation.
Collapse
Affiliation(s)
| | - Fergus E Poynton
- School of Chemistry, Trinity College Dublin, Dublin, 2, Ireland.,Trinity Biomedical Sciences Institute (TBSI), Trinity College Dublin, Dublin, 2, Ireland
| | | | - Thorfinnur Gunnlaugsson
- School of Chemistry, Trinity College Dublin, Dublin, 2, Ireland.,Trinity Biomedical Sciences Institute (TBSI), Trinity College Dublin, Dublin, 2, Ireland
| | - Christine J Cardin
- Department of Chemistry, University of Reading, Whiteknights, Reading, RG6 6AD, UK
| | | | - Michael Towrie
- Rutherford Appleton Laboratory, STFC, Harwell Campus, OX11 0FA, UK
| | - John M Kelly
- School of Chemistry, Trinity College Dublin, Dublin, 2, Ireland
| | - Susan J Quinn
- School of Chemistry, University College Dublin, Dublin, 4, Ireland
| |
Collapse
|
40
|
Kharel P, Becker G, Tsvetkov V, Ivanov P. Properties and biological impact of RNA G-quadruplexes: from order to turmoil and back. Nucleic Acids Res 2020; 48:12534-12555. [PMID: 33264409 PMCID: PMC7736831 DOI: 10.1093/nar/gkaa1126] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/23/2020] [Accepted: 11/06/2020] [Indexed: 12/12/2022] Open
Abstract
Guanine-quadruplexes (G4s) are non-canonical four-stranded structures that can be formed in guanine (G) rich nucleic acid sequences. A great number of G-rich sequences capable of forming G4 structures have been described based on in vitro analysis, and evidence supporting their formation in live cells continues to accumulate. While formation of DNA G4s (dG4s) within chromatin in vivo has been supported by different chemical, imaging and genomic approaches, formation of RNA G4s (rG4s) in vivo remains a matter of discussion. Recent data support the dynamic nature of G4 formation in the transcriptome. Such dynamic fluctuation of rG4 folding-unfolding underpins the biological significance of these structures in the regulation of RNA metabolism. Moreover, rG4-mediated functions may ultimately be connected to mechanisms underlying disease pathologies and, potentially, provide novel options for therapeutics. In this framework, we will review the landscape of rG4s within the transcriptome, focus on their potential impact on biological processes, and consider an emerging connection of these functions in human health and disease.
Collapse
Affiliation(s)
- Prakash Kharel
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Gertraud Becker
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Vladimir Tsvetkov
- Computational Oncology Group, I. M. Sechenov First Moscow State Medical University, Moscow 119146, Russia
- Federal Research and Clinical Center for Physical-Chemical Medicine, Federal Medical Biological Agency, Moscow 119435, Russia
- A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow 117912, Russia
| | - Pavel Ivanov
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard Initiative for RNA Medicine, Boston, MA 02115, USA
| |
Collapse
|
41
|
Reddy Sannapureddi RK, Mohanty MK, Gautam AK, Sathyamoorthy B. Characterization of DNA G-quadruplex Topologies with NMR Chemical Shifts. J Phys Chem Lett 2020; 11:10016-10022. [PMID: 33179931 DOI: 10.1021/acs.jpclett.0c02969] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
G-quadruplexes are nucleic acid motifs formed by stacking of guanosine-tetrad pseudoplanes. They perform varied biological roles, and their distinctive structural features enable diverse applications. High-resolution structural characterization of G-quadruplexes is often time-consuming and expensive, calling for effective methods. Herein, we develop NMR chemical shifts and machine learning-based methodology that allows direct, rapid, and reliable analysis of canonical three-plane DNA G-quadruplexes sans isotopic enrichment. We show, for the first time, that each unique topology enforces a specific distribution of glycosidic torsion angles. Newly acquired carbon chemical shifts are exquisite probes for the dihedral angle distribution and provide immediate and unambiguous backbone topology assignment. The support vector machine learning methodology aids resonance assignment by providing plane indices for tetrad-forming guanosines. We further demonstrate the robustness by successful application of the methodology to a sequence that folds in two dissimilar topologies under different ionic conditions, providing its first atomic-level characterization.
Collapse
Affiliation(s)
| | - Manish Kumar Mohanty
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Madhya Pradesh 462066, India
| | - Anoop Kumar Gautam
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Madhya Pradesh 462066, India
| | - Bharathwaj Sathyamoorthy
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Madhya Pradesh 462066, India
| |
Collapse
|
42
|
Andrałojć W, Pasternak K, Sarzyńska J, Zielińska K, Kierzek R, Gdaniec Z. The origin of the high stability of 3'-terminal uridine tetrads: contributions of hydrogen bonding, stacking interactions, and steric factors evaluated using modified oligonucleotide analogs. RNA (NEW YORK, N.Y.) 2020; 26:2000-2016. [PMID: 32967936 PMCID: PMC7668245 DOI: 10.1261/rna.076539.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/17/2020] [Indexed: 05/09/2023]
Abstract
RNA G-quadruplexes fold almost exclusively into parallel-stranded structures and thus display much less structural diversity than their DNA counterparts. However, also among RNA G-quadruplexes peculiar structural elements can be found which are capable of reshaping the physico-chemical properties of the folded structure. A striking example is provided by a uridine tetrad (U-tetrad) placed on the 3'-terminus of the tetramolecular G-quadruplex. In this context, the U-tetrad adopts a unique conformation involving chain reversal and is responsible for a tremendous stabilization of the G-quadruplex (ΔTm up to 30°C). In this report, we attempt to rationalize the origin of this stabilizing effect by concurrent structural, thermal stability, and molecular dynamics studies of a series of G-quadruplexes with subtle chemical modifications at their 3'-termini. Our results provide detailed insights into the energetics of the "reversed" U-tetrad motif and the requirements for its formation. They point to the importance of the 2'OH to phosphate hydrogen bond and preferential stacking interactions for the formation propensity and stability of the motif.
Collapse
Affiliation(s)
- Witold Andrałojć
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Karol Pasternak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Joanna Sarzyńska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Karolina Zielińska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Ryszard Kierzek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Zofia Gdaniec
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| |
Collapse
|
43
|
Haase L, Weisz K. Locked nucleic acid building blocks as versatile tools for advanced G-quadruplex design. Nucleic Acids Res 2020; 48:10555-10566. [PMID: 32890406 PMCID: PMC7544228 DOI: 10.1093/nar/gkaa720] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/24/2020] [Accepted: 08/20/2020] [Indexed: 01/21/2023] Open
Abstract
A hybrid-type G-quadruplex is modified with LNA (locked nucleic acid) and 2′-F-riboguanosine in various combinations at the two syn positions of its third antiparallel G-tract. LNA substitution in the central tetrad causes a complete rearrangement to either a V-loop or antiparallel structure, depending on further modifications at the 5′-neighboring site. In the two distinct structural contexts, LNA-induced stabilization is most effective compared to modifications with other G surrogates, highlighting a potential use of LNA residues for designing not only parallel but various more complex G4 structures. For instance, the conventional V-loop is a structural element strongly favored by an LNA modification at the V-loop 3′-end in contrast with an alternative V-loop, clearly distinguishable by altered conformational properties and base-backbone interactions as shown in a detailed analysis of V-loop structures.
Collapse
Affiliation(s)
- Linn Haase
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany
| | - Klaus Weisz
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany
| |
Collapse
|
44
|
Ngoc Nguyen TQ, Lim KW, Phan AT. Duplex formation in a G-quadruplex bulge. Nucleic Acids Res 2020; 48:10567-10575. [PMID: 32960213 PMCID: PMC7544226 DOI: 10.1093/nar/gkaa738] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/21/2020] [Accepted: 08/31/2020] [Indexed: 01/05/2023] Open
Abstract
Beyond the consensus definition of G-quadruplex-forming motifs with tracts of continuous guanines, G-quadruplexes harboring bulges in the G-tetrad core are prevalent in the human genome. Here, we study the incorporation of a duplex hairpin within a bulge of a G-quadruplex. The NMR solution structure of a G-quadruplex containing a duplex bulge was resolved, revealing the structural details of the junction between the duplex bulge and the G-quadruplex. Unexpectedly, instead of an orthogonal connection the duplex stem was observed to stack below the G-quadruplex forming a unique quadruplex–duplex junction. Breaking up of the immediate base pair step at the junction, coupled with a narrowing of the duplex groove within the context of the bulge, led to a progressive transition between the quadruplex and duplex segments. This study revealed that a duplex bulge can be formed at various positions of a G-quadruplex scaffold. In contrast to a non-structured bulge, the stability of a G-quadruplex slightly increases with an increase in the duplex bulge size. A G-quadruplex structure containing a duplex bulge of up to 33 nt in size was shown to form, which was much larger than the previously reported 7-nt bulge. With G-quadruplexes containing duplex bulges representing new structural motifs with potential biological significance, our findings would broaden the definition of potential G-quadruplex-forming sequences.
Collapse
Affiliation(s)
- Thi Quynh Ngoc Nguyen
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Kah Wai Lim
- 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
| |
Collapse
|
45
|
Lenarčič Živković M, Rozman J, Plavec J. Structure of a DNA G-Quadruplex Related to Osteoporosis with a G-A Bulge Forming a Pseudo-loop. Molecules 2020; 25:E4867. [PMID: 33096904 PMCID: PMC7588008 DOI: 10.3390/molecules25204867] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/19/2020] [Accepted: 10/19/2020] [Indexed: 11/30/2022] Open
Abstract
Bone remodeling is a fine-tuned process principally regulated by a cascade triggered by interaction of receptor activator of NF-κB (RANK) and RANK ligand (RANKL). Excessive activity of the RANKL gene leads to increased bone resorption and can influence the incidence of osteoporosis. Although much has been learned about the intracellular signals activated by RANKL/RANK complex, significantly less is known about the molecular mechanisms of regulation of RANKL expression. Here, we report on the structure of an unprecedented DNA G-quadruplex, well-known secondary structure-mediated gene expression regulator, formed by a G-rich sequence found in the regulatory region of a RANKL gene. Solution-state NMR structural study reveals the formation of a three-layered parallel-type G-quadruplex characterized by an unique features, including a G-A bulge. Although a guanine within a G-tract occupies syn glycosidic conformation, bulge-forming residues arrange in a pseudo-loop conformation to facilitate partial 5/6-ring stacking, typical of G-quadruplex structures with parallel G-tracts orientation. Such distinctive structural features protruding from the core of the structure can represent a novel platform for design of highly specific ligands with anti-osteoporotic function. Additionally, our study suggests that the expression of RANKL gene may be regulated by putative folding of its G-rich region into non-B-DNA structure(s).
Collapse
Affiliation(s)
- Martina Lenarčič Živković
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia;
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Jan Rozman
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia;
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia;
- EN-FIST Centre of Excellence, Trg OF 13, 1000 Ljubljana, Slovenia
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| |
Collapse
|
46
|
Popenda M, Miskiewicz J, Sarzynska J, Zok T, Szachniuk M. Topology-based classification of tetrads and quadruplex structures. Bioinformatics 2020; 36:1129-1134. [PMID: 31588513 PMCID: PMC7031778 DOI: 10.1093/bioinformatics/btz738] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 08/12/2019] [Accepted: 09/25/2019] [Indexed: 12/02/2022] Open
Abstract
Motivation Quadruplexes attract the attention of researchers from many fields of bio-science. Due to a specific structure, these tertiary motifs are involved in various biological processes. They are also promising therapeutic targets in many strategies of drug development, including anticancer and neurological disease treatment. The uniqueness and diversity of their forms cause that quadruplexes show great potential in novel biological applications. The existing approaches for quadruplex analysis are based on sequence or 3D structure features and address canonical motifs only. Results In our study, we analyzed tetrads and quadruplexes contained in nucleic acid molecules deposited in Protein Data Bank. Focusing on their secondary structure topology, we adjusted its graphical diagram and proposed new dot-bracket and arc representations. We defined the novel classification of these motifs. It can handle both canonical and non-canonical cases. Based on this new taxonomy, we implemented a method that automatically recognizes the types of tetrads and quadruplexes occurring as unimolecular structures. Finally, we conducted a statistical analysis of these motifs found in experimentally determined nucleic acid structures in relation to the new classification. Availability and implementation https://github.com/tzok/eltetrado/ Supplementary information Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Mariusz Popenda
- Department of Structural Bioinformatics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan 61-704, Poland
| | - Joanna Miskiewicz
- Institute of Computing Science and European Centre for Bioinformatics and Genomics, Poznan University of Technology, Poznan 60-965, Poland
| | - Joanna Sarzynska
- Department of Structural Bioinformatics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan 61-704, Poland
| | - Tomasz Zok
- Institute of Computing Science and European Centre for Bioinformatics and Genomics, Poznan University of Technology, Poznan 60-965, Poland.,Poznan Supercomputing and Networking Center, Poznan 61-139, Poland
| | - Marta Szachniuk
- Department of Structural Bioinformatics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan 61-704, Poland.,Institute of Computing Science and European Centre for Bioinformatics and Genomics, Poznan University of Technology, Poznan 60-965, Poland
| |
Collapse
|
47
|
Miskiewicz J, Sarzynska J, Szachniuk M. How bioinformatics resources work with G4 RNAs. Brief Bioinform 2020; 22:5902714. [PMID: 32898859 PMCID: PMC8138894 DOI: 10.1093/bib/bbaa201] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 12/17/2022] Open
Abstract
Quadruplexes (G4s) are of interest, which increases with the number of identified G4 structures and knowledge about their biomedical potential. These unique motifs form in many organisms, including humans, where their appearance correlates with various diseases. Scientists store and analyze quadruplexes using recently developed bioinformatic tools—many of them focused on DNA structures. With an expanding collection of G4 RNAs, we check how existing tools deal with them. We review all available bioinformatics resources dedicated to quadruplexes and examine their usefulness in G4 RNA analysis. We distinguish the following subsets of resources: databases, tools to predict putative quadruplex sequences, tools to predict secondary structure with quadruplexes and tools to analyze and visualize quadruplex structures. We share the results obtained from processing specially created RNA datasets with these tools. Contact: mszachniuk@cs.put.poznan.pl Supplementary information: Supplementary data are available at Briefings in Bioinformatics online.
Collapse
Affiliation(s)
- Joanna Miskiewicz
- Institute of Computing Science and European Centre for Bioinformatics and Genomics, Poznan University of Technology, Piotrowo 2, 60-965 Poznan, Poland
| | - Joanna Sarzynska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Marta Szachniuk
- Institute of Computing Science and European Centre for Bioinformatics and Genomics, Poznan University of Technology, Piotrowo 2, 60-965 Poznan, Poland
| |
Collapse
|
48
|
Bua G, Tedesco D, Conti I, Reggiani A, Bartolini M, Gallinella G. No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions. Viruses 2020; 12:v12090935. [PMID: 32854437 PMCID: PMC7552014 DOI: 10.3390/v12090935] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/20/2020] [Accepted: 08/21/2020] [Indexed: 12/11/2022] Open
Abstract
Parvovirus B19 (B19V), an ssDNA virus in the family Parvoviridae, is a human pathogenic virus, responsible for a wide range of clinical manifestations, still in need of effective and specific antivirals. DNA structures, including G-quadruplex (G4), have been recognised as relevant functional features in viral genomes, and small-molecule ligands binding to these structures are promising antiviral compounds. Bioinformatic tools predict the presence of potential G4 forming sequences (PQSs) in the genome of B19V, raising interest as targets for antiviral strategies. Predictions locate PQSs in the genomic terminal regions, in proximity to replicative origins. The actual propensity of these PQSs to form G4 structures was investigated by circular dichroism spectroscopic analysis on synthetic oligonucleotides of corresponding sequences. No signature of G4 structures was detected, and the interaction with the G4 ligand BRACO-19 (N,N'-(9-{[4-(dimethylamino)phenyl]amino}acridine-3,6-diyl)bis(3-pyrrolidin-1-ylpropanamide) did not appear consistent with the stabilisation of G4 structures. Any potential role of PQSs in the viral lifecycle was then assessed in an in vitro infection model system, by evaluating any variation in replication or expression of B19V in the presence of the G4 ligands BRACO-19 and pyridostatin. Neither showed a significant inhibitory activity on B19V replication or expression. Experimental challenge did not support bioinformatic predictions. The terminal regions of B19V are characterised by relevant sequence and symmetry constraints, which are functional to viral replication. Our experiments suggest that these impose a stringent requirement prevailing over the propensity of forming actual G4 structures.
Collapse
|
49
|
Ou A, Schmidberger JW, Wilson KA, Evans CW, Hargreaves JA, Grigg M, O'Mara ML, Iyer KS, Bond CS, Smith NM. High resolution crystal structure of a KRAS promoter G-quadruplex reveals a dimer with extensive poly-A π-stacking interactions for small-molecule recognition. Nucleic Acids Res 2020; 48:5766-5776. [PMID: 32313953 PMCID: PMC7261167 DOI: 10.1093/nar/gkaa262] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 04/02/2020] [Accepted: 04/04/2020] [Indexed: 12/13/2022] Open
Abstract
Aberrant KRAS signaling is a driver of many cancers and yet remains an elusive target for drug therapy. The nuclease hypersensitive element of the KRAS promoter has been reported to form secondary DNA structures called G-quadruplexes (G4s) which may play important roles in regulating KRAS expression, and has spurred interest in structural elucidation studies of the KRAS G-quadruplexes. Here, we report the first high-resolution crystal structure (1.6 Å) of a KRAS G-quadruplex as a 5'-head-to-head dimer with extensive poly-A π-stacking interactions observed across the dimer. Molecular dynamics simulations confirmed that the poly-A π-stacking interactions are also maintained in the G4 monomers. Docking and molecular dynamics simulations with two G4 ligands that display high stabilization of the KRAS G4 indicated the poly-A loop was a binding site for these ligands in addition to the 5'-G-tetrad. Given sequence and structural variability in the loop regions provide the opportunity for small-molecule targeting of specific G4s, we envisage this high-resolution crystal structure for the KRAS G-quadruplex will aid in the rational design of ligands to selectively target KRAS.
Collapse
Affiliation(s)
- Arnold Ou
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Jason W Schmidberger
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Katie A Wilson
- Research School of Chemistry, The Australian National University, Canberra, ACT 2601, Australia
| | - Cameron W Evans
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Jessica A Hargreaves
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Melanie Grigg
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Megan L O'Mara
- Research School of Chemistry, The Australian National University, Canberra, ACT 2601, Australia
| | - K Swaminathan Iyer
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Charles S Bond
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Nicole M Smith
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| |
Collapse
|
50
|
Lat PK, Liu K, Kumar DN, Wong KKL, Verheyen EM, Sen D. High specificity and tight spatial restriction of self-biotinylation by DNA and RNA G-Quadruplexes complexed in vitro and in vivo with Heme. Nucleic Acids Res 2020; 48:5254-5267. [PMID: 32329781 PMCID: PMC7261162 DOI: 10.1093/nar/gkaa281] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/24/2020] [Accepted: 04/09/2020] [Indexed: 12/20/2022] Open
Abstract
Guanine-rich, single-stranded DNAs and RNAs that fold to G-quadruplexes (GQs) are able to complex tightly with heme and display strongly enhanced peroxidase activity. Phenolic compounds are particularly good substrates for these oxidative DNAzymes and ribozymes; we recently showed that the use of biotin-tyramide as substrate can lead to efficient GQ self-biotinylation. Such biotinylated GQs are amenable to polymerase chain reaction amplification and should be useful for a relatively non-perturbative investigation of GQs as well as GQ-heme complexes within living cells. Here, we report that in mixed solutions of GQ and duplex DNA in vitro, GQ biotinylation is specifically >104-fold that of the duplex, even in highly concentrated DNA gels; that a three-quartet GQ is tagged by up to four biotins, whose attachment occurs more or less uniformly along the GQ but doesn't extend significantly into a duplex appended to the GQ. This self-biotinylation can be modulated or even abolished in the presence of strong GQ ligands that compete with heme. Finally, we report strong evidence for the successful use of this methodology for labeling DNA and RNA within live, freshly dissected Drosophila larval salivary glands.
Collapse
Affiliation(s)
- Prince Kumar Lat
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Kun Liu
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Dev N Kumar
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Kenneth K L Wong
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Esther M Verheyen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Dipankar Sen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.,Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| |
Collapse
|