1
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Peng HC, Mohan S, Huq MT, Bull JA, Michaud T, Piercy TC, Hilber S, Wettasinghe AP, Slinker JD, Kreutz C, Stelling AL. Isotope-Edited Variable Temperature Infrared Spectroscopy for Measuring Transition Temperatures of Single A-T Watson-Crick Base Pairs in DNA Duplexes. Anal Chem 2024; 96:8868-8874. [PMID: 38775341 DOI: 10.1021/acs.analchem.4c00056] [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: 06/05/2024]
Abstract
Experimental methods to determine transition temperatures for individual base pair melting events in DNA duplexes are lacking despite intense interest in these thermodynamic parameters. Here, we determine the dimensions of the thymine (T) C2═O stretching vibration when it is within the DNA duplex via isotopic substitutions at other atomic positions in the structure. First, we determined that this stretching state was localized enough to specific atoms in the molecule to make submolecular scale measurements of local structure and stability in high molecular weight complexes. Next, we develop a new isotope-edited variable temperature infrared method to measure melting transitions at various locations in a DNA structure. As an initial test of this "sub-molecular scale thermometer", we applied our T13C2 difference infrared signal to measure location-dependent melting temperatures (TmL) in a DNA duplex via variable temperature attenuated total reflectance Fourier transform infrared (VT-ATR-FTIR) spectroscopy. We report that the TmL of a single Watson-Crick A-T base pair near the end of an A-T rich sequence (poly T) is ∼34.9 ± 0.7°C. This is slightly lower than the TmL of a single base pair near the middle position of the poly T sequence (TmL ∼35.6±0.2°C). In addition, we also report that the TmL of a single Watson-Crick A-T base pair near the end of a 50% G-C sequence (12-mer) is ∼52.5 ± 0.3°C, which is slightly lower than the global melting Tm of the 12-mer sequence (TmL ∼54.0±0.9°C). Our results provide direct physical evidence for end fraying in DNA sequences with our novel spectroscopic methods.
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Affiliation(s)
- Hao-Che Peng
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Shrijaa Mohan
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Muhammad T Huq
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Julie A Bull
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Troy Michaud
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Turner C Piercy
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Stefan Hilber
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck 6020, Austria
| | - Ashan P Wettasinghe
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Jason D Slinker
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck 6020, Austria
| | - Allison L Stelling
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
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2
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Wu Y, Guo J, Li W, Xiu X, Thirunavukarasu D, Wang Y, Wang K, Chen W, Yu Zhang D, Yang X, Fan C, Song P. Enhanced Detection of Novel Low-Frequency Gene Fusions via High-Yield Ligation and Multiplexed Enrichment Sequencing. Angew Chem Int Ed Engl 2024; 63:e202316484. [PMID: 38494435 DOI: 10.1002/anie.202316484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 03/19/2024]
Abstract
Panel-based methods are commonly employed for the analysis of novel gene fusions in precision diagnostics and new drug development in cancer. However, these methods are constrained by limitations in ligation yield and the enrichment of novel gene fusions with low variant allele frequencies. In this study, we conducted a pioneering investigation into the stability of double-stranded adapter DNA, resulting in improved ligation yield and enhanced conversion efficiency. Additionally, we implemented blocker displacement amplification, achieving a remarkable 7-fold enrichment of novel gene fusions. Leveraging the pre-enrichment achieved with this approach, we successfully applied it to Nanopore sequencing, enabling ultra-fast analysis of novel gene fusions within one hour with high sensitivity. This method offers a robust and remarkably sensitive mean of analyzing novel gene fusions, promising the discovery of pivotal biomarkers that can significantly improve cancer diagnostics and the development of new therapeutic strategies.
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Affiliation(s)
- Yi Wu
- School of Biomedical Engineering, Zhangjiang Institute for Advanced Study and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jinxiao Guo
- Shanghai Sixth People's Hospital Affiliated to, Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China
| | - Wenjun Li
- NuProbe USA, Inc., 2575 West Bellfort Avenue, Ste. 200 Houston, TX 77054, USA
| | - Xuehao Xiu
- School of Biomedical Engineering, Zhangjiang Institute for Advanced Study and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | | | - Yudong Wang
- Department of Gynecologic Oncology, The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Kai Wang
- Department of Respiratory and Critical Care Medicine, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang, 322000, China
| | - Weiyu Chen
- Department of Respiratory and Critical Care Medicine, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang, 322000, China
| | - David Yu Zhang
- NuProbe USA, Inc., 2575 West Bellfort Avenue, Ste. 200 Houston, TX 77054, USA
| | - Xiurong Yang
- School of Chemistry and Chemical Engineering, New Cornerstone Science Laboratory, Frontiers Science Center for Transformative Molecules, Zhangjiang Institute for Advanced Study and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Chunhai Fan
- School of Chemistry and Chemical Engineering, New Cornerstone Science Laboratory, Frontiers Science Center for Transformative Molecules, Zhangjiang Institute for Advanced Study and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ping Song
- School of Biomedical Engineering, Zhangjiang Institute for Advanced Study and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
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3
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Todisco M, Ding D, Szostak JW. Transient states during the annealing of mismatched and bulged oligonucleotides. Nucleic Acids Res 2024; 52:2174-2187. [PMID: 38348869 PMCID: PMC10954449 DOI: 10.1093/nar/gkae091] [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: 11/09/2023] [Revised: 01/19/2024] [Accepted: 01/29/2024] [Indexed: 03/22/2024] Open
Abstract
Oligonucleotide hybridization is crucial in various biological, prebiotic and nanotechnological processes, including gene regulation, non-enzymatic primer extension and DNA nanodevice assembly. Although extensive research has focused on the thermodynamics and kinetics of nucleic acid hybridization, the behavior of complex mixtures and the outcome of competition for target binding remain less well understood. In this study, we investigate the impact of mismatches and bulges in a 12 bp DNA or RNA duplex on its association (kon) and dissociation (koff) kinetics. We find that such defects have relatively small effects on the association kinetics, while the dissociation kinetics vary in a position-dependent manner by up to 6 orders of magnitude. Building upon this observation, we explored a competition scenario involving multiple oligonucleotides, and observed a transient low specificity of probe hybridization to fully versus partially complementary targets in solution. We characterize these long-lived metastable states and their evolution toward equilibrium, and show that sufficiently long-lived mis-paired duplexes can serve as substrates for prebiotically relevant chemical copying reactions. Our results suggest that transient low accuracy states may spontaneously emerge within all complex nucleic acid systems comprising a large enough number of competing strands, with potential repercussions for gene regulation in the realm of modern biology and the prebiotic preservation of genetic information.
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Affiliation(s)
- Marco Todisco
- Howard Hughes Medical Institute, Department of Chemistry, The University of Chicago, Chicago, IL 60637, USA
| | - Dian Ding
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA
| | - Jack W Szostak
- Howard Hughes Medical Institute, Department of Chemistry, The University of Chicago, Chicago, IL 60637, USA
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4
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Tobiason M, Yurke B, Hughes WL. Generation of DNA oligomers with similar chemical kinetics via in-silico optimization. Commun Chem 2023; 6:226. [PMID: 37853171 PMCID: PMC10584830 DOI: 10.1038/s42004-023-01026-w] [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: 02/22/2023] [Accepted: 10/10/2023] [Indexed: 10/20/2023] Open
Abstract
Networks of interacting DNA oligomers are useful for applications such as biomarker detection, targeted drug delivery, information storage, and photonic information processing. However, differences in the chemical kinetics of hybridization reactions, referred to as kinetic dispersion, can be problematic for some applications. Here, it is found that limiting unnecessary stretches of Watson-Crick base pairing, referred to as unnecessary duplexes, can yield exceptionally low kinetic dispersions. Hybridization kinetics can be affected by unnecessary intra-oligomer duplexes containing only 2 base-pairs, and such duplexes explain up to 94% of previously reported kinetic dispersion. As a general design rule, it is recommended that unnecessary intra-oligomer duplexes larger than 2 base-pairs and unnecessary inter-oligomer duplexes larger than 7 base-pairs be avoided. Unnecessary duplexes typically scale exponentially with network size, and nearly all networks contain unnecessary duplexes substantial enough to affect hybridization kinetics. A new method for generating networks which utilizes in-silico optimization to mitigate unnecessary duplexes is proposed and demonstrated to reduce in-vitro kinetic dispersions as much as 96%. The limitations of the new design rule and generation method are evaluated in-silico by creating new oligomers for several designs, including three previously programmed reactions and one previously engineered structure.
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Affiliation(s)
- Michael Tobiason
- Department of Computer Science, Boise State University, Boise, ID, USA.
- Micron School of Materials Science & Engineering, Boise State University, Boise, ID, USA.
| | - Bernard Yurke
- Micron School of Materials Science & Engineering, Boise State University, Boise, ID, USA
- Department of Electrical & Computer Engineering, Boise State University, Boise, ID, USA
| | - William L Hughes
- School of Engineering, University of British Columbia Okanagan Campus, Kelowna, BC, Canada.
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5
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Metternich JT, Wartmann JAC, Sistemich L, Nißler R, Herbertz S, Kruss S. Near-Infrared Fluorescent Biosensors Based on Covalent DNA Anchors. J Am Chem Soc 2023. [PMID: 37367958 DOI: 10.1021/jacs.3c03336] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Semiconducting single-walled carbon nanotubes (SWCNTs) are versatile near-infrared (NIR) fluorophores. They are noncovalently modified to create sensors that change their fluorescence when interacting with biomolecules. However, noncovalent chemistry has several limitations and prevents a consistent way to molecular recognition and reliable signal transduction. Here, we introduce a widely applicable covalent approach to create molecular sensors without impairing the fluorescence in the NIR (>1000 nm). For this purpose, we attach single-stranded DNA (ssDNA) via guanine quantum defects as anchors to the SWCNT surface. A connected sequence without guanines acts as flexible capture probe allowing hybridization with complementary nucleic acids. Hybridization modulates the SWCNT fluorescence and the magnitude increases with the length of the capture sequence (20 > 10 ≫ 6 bases). The incorporation of additional recognition units via this sequence enables a generic route to NIR fluorescent biosensors with improved stability. To demonstrate the potential, we design sensors for bacterial siderophores and the SARS CoV-2 spike protein. In summary, we introduce covalent guanine quantum defect chemistry as rational design concept for biosensors.
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Affiliation(s)
- Justus T Metternich
- Department of Chemistry, Ruhr-University Bochum, 44801 Bochum, Germany
- Biomedical Nanosensors, Fraunhofer Institute for Microelectronic Circuits and Systems, 47057 Duisburg, Germany
| | | | - Linda Sistemich
- Department of Chemistry, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Robert Nißler
- Nanoparticle Systems Engineering Laboratory, ETH Zürich, 8092 Zürich, Switzerland
- Laboratory for Particles-Biology Interactions, Empa, 9014 St. Gallen, Switzerland
| | - Svenja Herbertz
- Biomedical Nanosensors, Fraunhofer Institute for Microelectronic Circuits and Systems, 47057 Duisburg, Germany
| | - Sebastian Kruss
- Department of Chemistry, Ruhr-University Bochum, 44801 Bochum, Germany
- Biomedical Nanosensors, Fraunhofer Institute for Microelectronic Circuits and Systems, 47057 Duisburg, Germany
- Center for Nanointegration Duisburg-Essen (CENIDE), 47057 Duisburg, Germany
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6
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Meng W, Peng HC, Liu Y, Stelling A, Wang L. Modeling the Infrared Spectroscopy of Oligonucleotides with 13C Isotope Labels. J Phys Chem B 2023; 127:2351-2361. [PMID: 36898003 DOI: 10.1021/acs.jpcb.2c08915] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The carbonyl stretching modes have been widely used in linear and two-dimensional infrared (IR) spectroscopy to probe the conformation, interaction, and biological functions of nucleic acids. However, due to their universal appearance in nucleobases, the IR absorption bands of nucleic acids are often highly congested in the 1600-1800 cm-1 region. Following the fruitful applications in proteins, 13C isotope labels have been introduced to the IR measurements of oligonucleotides to reveal their site-specific structural fluctuations and hydrogen bonding conditions. In this work, we combine recently developed frequency and coupling maps to develop a theoretical strategy that models the IR spectra of oligonucleotides with 13C labels directly from molecular dynamics simulations. We apply the theoretical method to nucleoside 5'-monophosphates and DNA double helices and demonstrate how elements of the vibrational Hamiltonian determine the spectral features and their changes upon isotope labeling. Using the double helices as examples, we show that the calculated IR spectra are in good agreement with experiments and the 13C isotope labeling technique can potentially be applied to characterize the stacking configurations and secondary structures of nucleic acids.
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Affiliation(s)
- Wenting Meng
- Department of Chemistry and Chemical Biology, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Hao-Che Peng
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Yuanhao Liu
- Department of Statistics, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Allison Stelling
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Lu Wang
- Department of Chemistry and Chemical Biology, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
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7
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Howe CP, Greetham GM, Procacci B, Parker AW, Hunt NT. Sequence-Dependent Melting and Refolding Dynamics of RNA UNCG Tetraloops Using Temperature-Jump/Drop Infrared Spectroscopy. J Phys Chem B 2023; 127:1586-1597. [PMID: 36787177 PMCID: PMC9969394 DOI: 10.1021/acs.jpcb.2c08709] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Time-resolved temperature-jump/drop infrared (IR) spectroscopy has been used to measure the impact of stem base sequence on the melting and refolding dynamics of ribonucleic acid (RNA) tetraloops. A series of three 12-nucleotide RNA hairpin sequences were studied, each featuring a UACG tetraloop motif and a double-stranded stem containing four base pairs. In each case, the stem comprised three GC pairs plus a single AU base pair inserted at the closing point of the loop (RNAloop), in the middle of the stem (RNAmid), or at the stem terminus (RNAend). Results from analogous DNA tetraloop (TACG) sequences were also obtained. Inclusion of AU or AT base pairs in the stem leads to faster melting of the stem-loop structure compared to a stem sequence featuring four GC base pairs while refolding times were found to be slower, consistent with a general reduction in stem-loop stability caused by the AU/AT pair. Independent measurement of the dynamic timescales for melting and refolding of ring vibrational modes of guanine (GR) and adenine (AR) provided position-specific insight into hairpin dynamics. The GR-derived data showed that DNA sequences melted more quickly (0.5 ± 0.1 to 0.7 ± 0.1 μs at 70 °C) than analogous RNA sequences (4.3 ± 0.4 to 4.4 ± 0.3 μs at 70 °C). Position-sensitive data from the AR modes suggests that DNA hairpins begin melting from the terminal end of the stem toward the loop while RNA sequences begin melting from the loop. Refolding timescales for both RNA and DNA hairpins were found to be similar (250 ± 50 μs at 70 °C) except for RNAend and DNAloop which refolded much more slowly (746 ± 36 and 430 ± 31 μs, respectively), showing that the refolding pathway is significantly impaired by the placement of AU/AT pairs at different points in the stem. We conclude that conformational changes of analogous pairs of RNA and DNA tetraloops proceed by different mechanisms.
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Affiliation(s)
- C P Howe
- Department of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, U.K
| | - G M Greetham
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, Oxon, U.K
| | - B Procacci
- Department of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, U.K
| | - A W Parker
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, Oxon, U.K
| | - N T Hunt
- Department of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, U.K
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8
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Ding F, Cocco S, Raj S, Manosas M, Nguyen T, Spiering M, Bensimon D, Allemand JF, Croquette V. Displacement and dissociation of oligonucleotides during DNA hairpin closure under strain. Nucleic Acids Res 2022; 50:12082-12093. [PMID: 36478056 PMCID: PMC9757040 DOI: 10.1093/nar/gkac1113] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 10/19/2022] [Accepted: 11/07/2022] [Indexed: 12/12/2022] Open
Abstract
The hybridization kinetic of an oligonucleotide to its template is a fundamental step in many biological processes such as replication arrest, CRISPR recognition, DNA sequencing, DNA origami, etc. Although single kinetic descriptions exist for special cases of this problem, there are no simple general prediction schemes. In this work, we have measured experimentally, with no fluorescent labelling, the displacement of an oligonucleotide from its substrate in two situations: one corresponding to oligonucleotide binding/unbinding on ssDNA and one in which the oligonucleotide is displaced by the refolding of a dsDNA fork. In this second situation, the fork is expelling the oligonucleotide thus significantly reducing its residence time. To account for our data in these two situations, we have constructed a mathematical model, based on the known nearest neighbour dinucleotide free energies, and provided a good estimate of the residence times of different oligonucleotides (DNA, RNA, LNA) of various lengths in different experimental conditions (force, temperature, buffer conditions, presence of mismatches, etc.). This study provides a foundation for the dynamics of oligonucleotide displacement, a process of importance in numerous biological and bioengineering contexts.
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Affiliation(s)
- Fangyuan Ding
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
- Center for Complex Biological Systems, University of California, Irvine, CA 92697, USA
- Center for Synthetic Biology, Chao Family Comprehensive Cancer Center, Department of Developmental and Cell Biology, and Department of Pharmaceutical Sciences, University of California, Irvine, CA 92697, USA
| | - Simona Cocco
- Laboratoire de Physique de l’Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, Paris, France
| | - Saurabh Raj
- Kusuma School of Biological Sciences, Indian Institute of Technology, Delhi, 110016, India
| | - Maria Manosas
- Small Biosystems Lab, Departament de Física de la Matèria Condensada, Facultat de Física, Universitat de Barcelona, Carrer de Martí i Franquès, 1, 08028 Barcelona, Spain
- Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, 08028 Barcelona, Spain
| | - Thao Thi Thu Nguyen
- Center for Complex Biological Systems, University of California, Irvine, CA 92697, USA
| | - Michelle M Spiering
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
| | - David Bensimon
- Laboratoire de Physique de l’Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, Paris, France
- Institut de Biologie de l’École Normale Supérieure (IBENS), CNRS, Inserm, École Normale Supérieure, PSL Research University, F-75005, Paris, France
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Jean-François Allemand
- Laboratoire de Physique de l’Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, Paris, France
- Institut de Biologie de l’École Normale Supérieure (IBENS), CNRS, Inserm, École Normale Supérieure, PSL Research University, F-75005, Paris, France
| | - Vincent Croquette
- Laboratoire de Physique de l’Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, Paris, France
- Institut de Biologie de l’École Normale Supérieure (IBENS), CNRS, Inserm, École Normale Supérieure, PSL Research University, F-75005, Paris, France
- ESPCI Paris, Université PSL, Paris, France
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9
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Howe CP, Greetham GM, Procacci B, Parker AW, Hunt NT. Measuring RNA UNCG Tetraloop Refolding Dynamics Using Temperature-Jump/Drop Infrared Spectroscopy. J Phys Chem Lett 2022; 13:9171-9176. [PMID: 36166668 PMCID: PMC9549515 DOI: 10.1021/acs.jpclett.2c02338] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Determining the structural dynamics of RNA and DNA is essential to understanding their cellular function, but direct measurement of strand association or folding remains experimentally challenging. Here we illustrate a temperature-jump/drop method able to reveal refolding dynamics. Time-resolved temperature-jump/drop infrared spectroscopy is used to measure the melting and refolding dynamics of a 12-nucleotide RNA sequence comprising a UACG tetraloop and a four-base-pair double-stranded GC stem, comparing them to an equivalent DNA (TACG) sequence. Stem-loop melting occurred an order of magnitude more slowly in RNA than DNA (6.0 ± 0.1 μs versus 0.8 ± 0.1 μs at 70 °C). In contrast, the refolding dynamics of both sequences occurred on similar time scales (200 μs). While the melting and refolding dynamics of RNA and DNA hairpins both followed Arrhenius temperature dependences, refolding was characterized by an apparent negative activation energy, consistent with a mechanism involving multiple misfolded intermediates prior to zipping of the stem base pairs.
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Affiliation(s)
- C. P. Howe
- Department
of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, U.K.
| | - G. M. Greetham
- Central
Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory,
Harwell Oxford, Didcot, Oxon OX11 0QX, U.K.
| | - B. Procacci
- Department
of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, U.K.
| | - A. W. Parker
- Central
Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory,
Harwell Oxford, Didcot, Oxon OX11 0QX, U.K.
| | - N. T. Hunt
- Department
of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, U.K.
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10
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Todisco M, Szostak JW. Hybridization kinetics of out-of-equilibrium mixtures of short RNA oligonucleotides. Nucleic Acids Res 2022; 50:9647-9662. [PMID: 36099434 PMCID: PMC9508827 DOI: 10.1093/nar/gkac784] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/23/2022] [Accepted: 09/08/2022] [Indexed: 11/18/2022] Open
Abstract
Hybridization and strand displacement kinetics determine the evolution of the base paired configurations of mixtures of oligonucleotides over time. Although much attention has been focused on the thermodynamics of DNA and RNA base pairing in the scientific literature, much less work has been done on the time dependence of interactions involving multiple strands, especially in RNA. Here we provide a study of oligoribonucleotide interaction kinetics and show that it is possible to calculate the association, dissociation and strand displacement rates displayed by short oligonucleotides (5nt–12nt) that exhibit no expected secondary structure as simple functions of oligonucleotide length, CG content, ΔG of hybridization and ΔG of toehold binding. We then show that the resultant calculated kinetic parameters are consistent with the experimentally observed time dependent changes in concentrations of the different species present in mixtures of multiple competing RNA strands. We show that by changing the mixture composition, it is possible to create and tune kinetic traps that extend by orders of magnitude the typical sub-second hybridization timescale of two complementary oligonucleotides. We suggest that the slow equilibration of complex oligonucleotide mixtures may have facilitated the nonenzymatic replication of RNA during the origin of life.
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Affiliation(s)
- Marco Todisco
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA.,Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Jack W Szostak
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA.,Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA.,Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
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11
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Ohira M, Katashima T, Naito M, Aoki D, Yoshikawa Y, Iwase H, Takata SI, Miyata K, Chung UI, Sakai T, Shibayama M, Li X. Star-Polymer-DNA Gels Showing Highly Predictable and Tunable Mechanical Responses. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108818. [PMID: 35034389 DOI: 10.1002/adma.202108818] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Dynamically crosslinked gels are appealing materials for applications that require time-dependent mechanical responses. DNA duplexes are ideal crosslinkers for building such gels because of their excellent sequence addressability and flexible tunability in bond energy. However, the mechanical responses of most DNA gels are complicated and unpredictable. Here, a DNA gel with a highly homogeneous gel network and well predictable mechanical behaviors is demonstrated by using a pair of star-polymer-DNA precursors with presimulated DNA sequences showing the two-state transition. The melting curve analysis of the DNA gels reveals the good correspondence between the thermodynamic potentials of the DNA crosslinkers and the presimulated values by DNA calculators. Stress-relaxation tests and dissociation kinetics measurements show that the macroscopic relaxation time of the DNA gels is approximately equal to the lifetime of the DNA crosslinkers over 4 orders of magnitude from 0.1-2000 s. Furthermore, a series of durability tests find the DNA gels are hysteresis-less and self-healable after the applications of repeated temperature and mechanical stimuli. These results demonstrate the great potential of star-polymer-DNA precursors for building gels with predictable and tunable viscoelastic properties, suitable for applications such as stress-response extracellular matrices, injectable solids, and soft robotics.
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Affiliation(s)
- Masashi Ohira
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8685, Japan
| | - Takuya Katashima
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8685, Japan
| | - Mitsuru Naito
- Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Daisuke Aoki
- Department of Chemical Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8550, Japan
| | - Yusuke Yoshikawa
- Neutron Science Laboratory, Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan
| | - Hiroki Iwase
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), 162-1 Shirakata, Tokai, Naka, Ibaraki, 319-1106, Japan
| | - Shin-Ichi Takata
- Materials and Life Science Division, J-PARC Center, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai, Ibaraki, 319-1195, Japan
| | - Kanjiro Miyata
- Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Ung-Il Chung
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8685, Japan
| | - Takamasa Sakai
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8685, Japan
| | - Mitsuhiro Shibayama
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), 162-1 Shirakata, Tokai, Naka, Ibaraki, 319-1106, Japan
| | - Xiang Li
- Faculty of Advanced Life Science, Hokkaido University, Sapporo, 001-0021, Japan
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12
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Buhrke D, Ruf J, Heckmeier P, Hamm P. A stop-flow sample delivery system for transient spectroscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:123001. [PMID: 34972444 DOI: 10.1063/5.0068227] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/06/2021] [Indexed: 06/14/2023]
Abstract
A stop-flow sample delivery system for transient spectroscopy is presented, which is, in particular, suited for laser-based instruments (quantum-cascade lasers or amplified femtosecond lasers) with excitation pulse repetition rates in the range 10-100 Hz. Two pulsing micro-valves are mounted onto a flow cuvette designed for transient IR spectroscopy, which is integrated into a flow cycle driven by a peristaltic pump. The performance of the system is demonstrated with transient IR experiments of the trans-to-cis photoisomerization of a water-soluble azobenzene derivative. The sample stands still when the micro-valves are closed and is pushed out from the probe beam focus on a 1 ms timescale when opening the micro-valves. The setup is extremely sample efficient. It needs only small sample volumes, and at the same time, it enables excitation of a large fraction of molecules in solution.
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Affiliation(s)
- David Buhrke
- Department of Chemistry, University of Zurich, Winterthurerstr. 190, CH-8057 Zürich, Switzerland
| | - Jeannette Ruf
- Department of Chemistry, University of Zurich, Winterthurerstr. 190, CH-8057 Zürich, Switzerland
| | - Philipp Heckmeier
- Department of Chemistry, University of Zurich, Winterthurerstr. 190, CH-8057 Zürich, Switzerland
| | - Peter Hamm
- Department of Chemistry, University of Zurich, Winterthurerstr. 190, CH-8057 Zürich, Switzerland
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13
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Gu Y, Distler ME, Cheng HF, Huang C, Mirkin CA. A General DNA-Gated Hydrogel Strategy for Selective Transport of Chemical and Biological Cargos. J Am Chem Soc 2021; 143:17200-17208. [PMID: 34614359 DOI: 10.1021/jacs.1c08114] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The selective transport of molecular cargo is critical in many biological and chemical/materials processes and applications. Although nature has evolved highly efficient in vivo biological transport systems, synthetic transport systems are often limited by the challenges associated with fine-tuning interactions between cargo and synthetic or natural transport barriers. Herein, deliberately designed DNA-DNA interactions are explored as a new modality for selective DNA-modified cargo transport through DNA-grafted hydrogel supports. The chemical and physical characteristics of the cargo and hydrogel barrier, including the number of nucleic acid strands on the cargo (i.e., the cargo valency) and DNA-DNA binding strength, can be used to regulate the efficiency of cargo transport. Regimes exist where a cargo-barrier interaction is attractive enough to yield high selectivity yet high mobility, while there are others where the attractive interactions are too strong to allow mobility. These observations led to the design of a DNA-dendron transport tag, which can be used to universally modify macromolecular cargo so that the barrier can differentiate specific species to be transported. These novel transport systems that leverage DNA-DNA interactions provide new chemical insights into the factors that control selective cargo mobility in hydrogels and open the door to designing a wide variety of drug/probe-delivery systems.
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Affiliation(s)
- Yuwei Gu
- Department of Chemistry and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Max E Distler
- Department of Chemistry and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ho Fung Cheng
- Department of Chemistry and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Chi Huang
- Department of Chemistry and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Chad A Mirkin
- Department of Chemistry and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113, United States
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14
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Rieu M, Valle-Orero J, Ducos B, Allemand JF, Croquette V. Single-molecule kinetic locking allows fluorescence-free quantification of protein/nucleic-acid binding. Commun Biol 2021; 4:1083. [PMID: 34526657 PMCID: PMC8443601 DOI: 10.1038/s42003-021-02606-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 08/25/2021] [Indexed: 11/09/2022] Open
Abstract
Fluorescence-free micro-manipulation of nucleic acids (NA) allows the functional characterization of DNA/RNA processing proteins, without the interference of labels, but currently fails to detect and quantify their binding. To overcome this limitation, we developed a method based on single-molecule force spectroscopy, called kinetic locking, that allows a direct in vitro visualization of protein binding while avoiding any kind of chemical disturbance of the protein’s natural function. We validate kinetic locking by measuring accurately the hybridization energy of ultrashort nucleotides (5, 6, 7 bases) and use it to measure the dynamical interactions of Escherichia coli/E. coli RecQ helicase with its DNA substrate. Rieu et al. present a magnetic tweezers based single-molecule manipulation method, called kinetic locking, for direct detection of biomolecular binding without use of fluorescent probes. By measuring dynamical interactions of E. coli RecQ helicase with its DNA substrate, authors show that this method holds promise for studying DNA-DNA and DNA-protein interactions while avoiding the need for labelling.
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Affiliation(s)
- Martin Rieu
- Laboratoire de physique de l'Ecole Normale Supérieure (LPENS), ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, Paris, France. .,Institut de Biologie de l'Ecole Normale Supérieure (IBENS), ENS, Université PSL, CNRS, INSERM, Paris, France.
| | - Jessica Valle-Orero
- Laboratoire de physique de l'Ecole Normale Supérieure (LPENS), ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, Paris, France.,Institut de Biologie de l'Ecole Normale Supérieure (IBENS), ENS, Université PSL, CNRS, INSERM, Paris, France
| | - Bertrand Ducos
- Laboratoire de physique de l'Ecole Normale Supérieure (LPENS), ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, Paris, France.,Institut de Biologie de l'Ecole Normale Supérieure (IBENS), ENS, Université PSL, CNRS, INSERM, Paris, France
| | - Jean-François Allemand
- Laboratoire de physique de l'Ecole Normale Supérieure (LPENS), ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, Paris, France.,Institut de Biologie de l'Ecole Normale Supérieure (IBENS), ENS, Université PSL, CNRS, INSERM, Paris, France
| | - Vincent Croquette
- Laboratoire de physique de l'Ecole Normale Supérieure (LPENS), ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, Paris, France.,Institut de Biologie de l'Ecole Normale Supérieure (IBENS), ENS, Université PSL, CNRS, INSERM, Paris, France.,ESPCI Paris, Université PSL, 10 rue Vauquelin, 75005, Paris, France
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15
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Wong KL, Liu J. Factors and methods to modulate DNA hybridization kinetics. Biotechnol J 2021; 16:e2000338. [PMID: 34411451 DOI: 10.1002/biot.202000338] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/11/2021] [Accepted: 08/12/2021] [Indexed: 11/09/2022]
Abstract
DNA oligonucleotides are widely used in a diverse range of research fields from analytical chemistry, molecular biology, nanotechnology to drug delivery. In these applications, DNA hybridization is often the most important enabling reaction. Achieving control over hybridization kinetics and a high yield of hybridized products is needed to ensure high-quality and reproducible results. Since DNA strands are highly negatively charged and can also fold upon itself to form various intramolecular structures, DNA hybridization needs to overcome these barriers. Nucleation and diffusion are two main kinetic limiting steps although their relative importance differs in different conditions. The effects of length and sequence, temperature, pH, salt concentration, cationic polymers, organic solvents, freezing and crowding agents are summarized in the context of overcoming these barriers. This article will help researchers in the biotechnology-related fields to better understand and control DNA hybridization, as well as provide a landscape for future work in simulation and experiment to optimize DNA hybridization systems.
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Affiliation(s)
- Kingsley L Wong
- Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario, Canada
| | - Juewen Liu
- Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario, Canada
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16
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Dale J, Howe CP, Toncrova H, Fritzsch R, Greetham GM, Clark IP, Towrie M, Parker AW, McLeish TC, Hunt NT. Combining steady state and temperature jump IR spectroscopy to investigate the allosteric effects of ligand binding to dsDNA. Phys Chem Chem Phys 2021; 23:15352-15363. [PMID: 34254612 DOI: 10.1039/d1cp02233d] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Changes in the structural dynamics of double stranded (ds)DNA upon ligand binding have been linked to the mechanism of allostery without conformational change, but direct experimental evidence remains elusive. To address this, a combination of steady state infrared (IR) absorption spectroscopy and ultrafast temperature jump IR absorption measurements has been used to quantify the extent of fast (∼100 ns) fluctuations in (ds)DNA·Hoechst 33258 complexes at a range of temperatures. Exploiting the direct link between vibrational band intensities and base stacking shows that the absolute magnitude of the change in absorbance caused by fast structural fluctuations following the temperature jump is only weakly dependent on the starting temperature of the sample. The observed fast dynamics are some two orders of magnitude faster than strand separation and associated with all points along the 10-base pair duplex d(GCATATATCC). Binding the Hoechst 33258 ligand causes a small but consistent reduction in the extent of these fast fluctuations of base pairs located outside of the ligand binding region. These observations point to a ligand-induced reduction in the flexibility of the dsDNA near the binding site, consistent with an estimated allosteric propagation length of 15 Å, about 5 base pairs, which agrees well with both molecular simulation and coarse-grained statistical mechanics models of allostery leading to cooperative ligand binding.
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Affiliation(s)
- Jessica Dale
- Department of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, UK.
| | - C Peter Howe
- Department of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, UK.
| | - Hedvika Toncrova
- Department of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Robby Fritzsch
- Department of Physics, SUPA, University of Strathclyde, Glasgow, G4 0NG, UK
| | - Gregory M Greetham
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Ian P Clark
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Michael Towrie
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Anthony W Parker
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Thomas C McLeish
- Department of Physics, University of York, Heslington, York YO10 5DD, UK.
| | - Neil T Hunt
- Department of Chemistry and York Biomedical Research Institute, University of York, Heslington, York YO10 5DD, UK.
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17
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Laouer K, Schmid M, Wien F, Changenet P, Hache F. Folding Dynamics of DNA G-Quadruplexes Probed by Millisecond Temperature Jump Circular Dichroism. J Phys Chem B 2021; 125:8088-8098. [PMID: 34279936 DOI: 10.1021/acs.jpcb.1c01993] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
G-quadruplexes play important roles in cellular regulatory functions, but despite significant experimental and theoretical efforts, their folding mechanisms remain poorly understood. In this context, we developed a T-jump experiment to access the thermal denaturation and renaturation dynamics of short intramolecular G-quadruplexes in vitro, on the time scale of a few hundred milliseconds. With this new setup, we compared the thermal denaturation and renaturation kinetics of three antiparallel topologies made of the human telomeric sequences d[(5'-GGG(TTAGGG)3-3']/Na+ and d[5'-AGGG(TTAGGG)3-3']/Na+ and the thrombin-binding aptamer sequence d[5'-GGTTGGTGTGGTTGG-3']/K+, with those of the parallel topology made of the human CEB25 minisatellite d[5'-AAGGGTGGGTGTAAGTGTGGGTGGGT-3']/Na+. In all cases, exponential kinetics of the order of several hundred milliseconds were observed. Measurements performed for different initial temperatures revealed distinct denaturation and renaturation dynamics, ruling out a simple two-state mechanism. The parallel topology, in which all guanines adopt an anti conformation, displays much slower dynamics than antiparallel topologies associated with very low activation barriers. This behavior can be explained by the constrained conformational space due to the presence of the single-base propeller loops that likely hinders the movement of the coiled DNA strand and reduces the contribution of the entropy during the renaturation process at high temperatures.
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Affiliation(s)
- K Laouer
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS -INSERM, Institut Polytechnique de Paris, 91128 Cedex Palaiseau, France
| | - M Schmid
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS -INSERM, Institut Polytechnique de Paris, 91128 Cedex Palaiseau, France
| | - F Wien
- L'orme des merisiers, Synchrotron SOLEIL, 91192 Gif sur Yvette, France
| | - P Changenet
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS -INSERM, Institut Polytechnique de Paris, 91128 Cedex Palaiseau, France
| | - F Hache
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS -INSERM, Institut Polytechnique de Paris, 91128 Cedex Palaiseau, France
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18
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Fick RJ, Liu AY, Nussbaumer F, Kreutz C, Rangadurai A, Xu Y, Sommer RD, Shi H, Scheiner S, Stelling AL. Probing the Hydrogen-Bonding Environment of Individual Bases in DNA Duplexes with Isotope-Edited Infrared Spectroscopy. J Phys Chem B 2021; 125:7613-7627. [PMID: 34236202 PMCID: PMC8311644 DOI: 10.1021/acs.jpcb.1c01351] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
![]()
Measuring the strength
of the hydrogen bonds between DNA base pairs
is of vital importance for understanding how our genetic code is physically
accessed and recognized in cells, particularly during replication
and transcription. Therefore, it is important to develop probes for
these key hydrogen bonds (H-bonds) that dictate events critical to
cellular function, such as the localized melting of DNA. The vibrations
of carbonyl bonds are well-known probes of their H-bonding environment,
and their signals can be observed with infrared (IR) spectroscopy.
Yet, pinpointing a single bond of interest in the complex IR spectrum
of DNA is challenging due to the large number of carbonyl signals
that overlap with each other. Here, we develop a method using isotope
editing and infrared (IR) spectroscopy to isolate IR signals from
the thymine (T) C2=O carbonyl. We use solvatochromatic studies
to show that the TC2=O signal’s position in the IR spectrum
is sensitive to the H-bonding capacity of the solvent. Our results
indicate that C2=O of a single T base within DNA duplexes experiences
weak H-bonding interactions. This finding is consistent with the existence
of a third, noncanonical CH···O H-bond between adenine
and thymine in both Watson–Crick and Hoogsteen base pairs in
DNA.
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Affiliation(s)
- Robert J Fick
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Amy Y Liu
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Felix Nussbaumer
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck 6020, Austria
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck 6020, Austria
| | - Atul Rangadurai
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Yu Xu
- Department of Chemistry, Duke University, Durham, North Carolina 27710, United States
| | - Roger D Sommer
- Molecular Education, Technology, and Research Innovation Center, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Honglue Shi
- Department of Chemistry, Duke University, Durham, North Carolina 27710, United States
| | - Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
| | - Allison L Stelling
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States.,Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, United States
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19
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Rejali NA, Ye FD, Zuiter AM, Keller CC, Wittwer CT. Nearest-neighbour transition-state analysis for nucleic acid kinetics. Nucleic Acids Res 2021; 49:4574-4585. [PMID: 33823552 PMCID: PMC8096236 DOI: 10.1093/nar/gkab205] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/24/2021] [Accepted: 03/13/2021] [Indexed: 11/13/2022] Open
Abstract
We used stopped-flow to monitor hypochromicity for 43 oligonucleotide duplexes to study nucleic acid kinetics and extract transition-state parameters for association and dissociation. Reactions were performed in 1.0 M NaCl (for literature comparisons) and 2.2 mM MgCl2 (PCR conditions). Dissociation kinetics depended on sequence, increased exponentially with temperature, and transition-state parameters inversely correlated to thermodynamic parameters (r = -0.99). Association had no consistent enthalpic component, varied little with temperature or sequence, and poorly correlated to thermodynamic parameters (r = 0.28). Average association rates decreased 78% in MgCl2 compared to NaCl while dissociation was relatively insensitive to ionic conditions. A nearest-neighbour kinetic model for dissociation predicted rate constants within 3-fold of literature values (n = 11). However, a nearest-neighbour model for association appeared overparameterized and inadequate for predictions. Kinetic predictions were used to simulate published high-speed (<1 min) melting analysis and extreme (<2 min) PCR experiments. Melting simulations predicted apparent melting temperatures increase on average 2.4°C when temperature ramp rates increased from 0.1 to 32°C/s, compared to 2.8°C reported in the literature. PCR simulations revealed that denaturation kinetics are dependent on the thermocycling profile. Simulations overestimated annealing efficiencies at shorter annealing times and suggested that polymerase interactions contribute to primer-template complex stability at extension temperatures.
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Affiliation(s)
- Nick A Rejali
- Department of Pathology, University of Utah, Salt Lake City, UT 84132, USA
| | - Felix D Ye
- Department of Pathology, University of Utah, Salt Lake City, UT 84132, USA
| | - Aisha M Zuiter
- Department of Pathology, University of Utah, Salt Lake City, UT 84132, USA
| | - Caroline C Keller
- Department of Pathology, University of Utah, Salt Lake City, UT 84132, USA
| | - Carl T Wittwer
- Department of Pathology, University of Utah, Salt Lake City, UT 84132, USA
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20
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Li L, Wang H, Xiong C, Luo D, Chen H, Liu Y. Quantify the combined effects of temperature and force on the stability of DNA hairpin. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:185102. [PMID: 33711825 DOI: 10.1088/1361-648x/abee38] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 03/12/2021] [Indexed: 06/12/2023]
Abstract
OxDNA, as a successful coarse-grain model, has been applied to reproduce the thermodynamic and mechanical properties of both single- and double-stranded DNA. In current simulation, oxDNA is extended to explore the combined effects of temperature and force on the stability of DNA hairpin and its free energy landscape. Simulations were carried out at different forces and temperatures, at each temperature, a 18-base-pair DNA hairpin dynamically transited between folded state and unfolded state, and the separation between two states is consistent with the full contour length of single-stranded DNA in the unfolded state. Two methods were used to identify the critical force of DNA hairpin at each temperature and the critical forces obtained from two methods were consistent with each other and gradually decreased with the increasing temperature from 300 K to 326 K. The critical force at 300 K is reasonably consistent with the single molecule result of DNA hairpin with the same stem length. The two-state free energy landscape can be elucidated from the probability distribution of DNA hairpin extension and its dependence on the force and temperature is totally different. The increasing temperature not only reduces the free energy barrier, but also alters the position of transition point along the extension coordinate, resulting in the reduction of folding distance and the extension of unfolding distance, but their sum is not obviously dependent on the temperature. Generally, an assumption that the location of transition state in two-state energy landscape is independent of the stretching force is used to analyze the data of the single molecule experiment, but current simulation results indicate that effects of stretching forces on the location of transition state in two-state energy landscape are dependent on temperature. At relatively high temperature, stretching force can also change the location of transition state in the free energy landscape.
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Affiliation(s)
- Lin Li
- College of Physics, Guizhou University, Guiyang 550025, People's Republic of China
| | - Hongchang Wang
- School of Physics and Electronic Science, Guizhou Normal University, Guiyang 550025, People's Republic of China
| | - Caiyun Xiong
- College of Physics, Guizhou University, Guiyang 550025, People's Republic of China
| | - Di Luo
- College of Physics, Guizhou University, Guiyang 550025, People's Republic of China
| | - Hu Chen
- Research Institute for Biomimetics and Soft Matter, Fujian Provincial Key Lab for Soft Functional Materials Research, Department of Physics, Xiamen University, Xiamen, People's Republic of China
| | - Yanhui Liu
- College of Physics, Guizhou University, Guiyang 550025, People's Republic of China
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21
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Menssen RJ, Kimmel GJ, Tokmakoff A. Investigation into the mechanism and dynamics of DNA association and dissociation utilizing kinetic Monte Carlo simulations. J Chem Phys 2021; 154:045101. [PMID: 33514113 DOI: 10.1063/5.0035187] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
In this work, we present a kinetic Markov state Monte Carlo model designed to complement temperature-jump (T-jump) infrared spectroscopy experiments probing the kinetics and dynamics of short DNA oligonucleotides. The model is designed to be accessible to experimental researchers in terms of both computational simplicity and expense while providing detailed insights beyond those provided by experimental methods. The model is an extension of a thermodynamic lattice model for DNA hybridization utilizing the formalism of the nucleation-zipper mechanism. Association and dissociation trajectories were generated utilizing the Gillespie algorithm and parameters determined via fitting the association and dissociation timescales to previously published experimental data. Terminal end fraying, experimentally observed following a rapid T-jump, in the sequence 5'-ATATGCATAT-3' was replicated by the model that also demonstrated that experimentally observed fast dynamics in the sequences 5'-C(AT)nG-3', where n = 2-6, were also due to terminal end fraying. The dominant association pathways, isolated by transition pathway theory, showed two primary motifs: initiating at or next to a G:C base pair, which is enthalpically favorable and related to the increased strength of G:C base pairs, and initiating in the center of the sequence, which is entropically favorable and related to minimizing the penalty associated with the decrease in configurational entropy due to hybridization.
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Affiliation(s)
- Ryan J Menssen
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA
| | - Gregory J Kimmel
- Moffitt Cancer Center, 12902 USF Magnolia Drive, Tampa, Florida 33612, USA
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA
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22
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Harashima T, Hasegawa Y, Kaneko S, Jono Y, Fujii S, Kiguchi M, Nishino T. Elementary processes of DNA surface hybridization resolved by single-molecule kinetics: implication for macroscopic device performance. Chem Sci 2020; 12:2217-2224. [PMID: 34163987 PMCID: PMC8179252 DOI: 10.1039/d0sc04449k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Direct monitoring of single-molecule reactions has recently become a promising means of mechanistic investigation. However, the resolution of reaction pathways from single-molecule experiments remains elusive, primarily because of interference from extraneous processes such as bulk diffusion. Herein, we report a single-molecule kinetic investigation of DNA hybridization on a metal surface, as an example of a bimolecular association reaction. The tip of the scanning tunneling microscope (STM) was functionalized with single-stranded DNA (ssDNA), and hybridization with its complementary strand on an Au(111) surface was detected by the increase in the electrical conductance associated with the electron transport through the resulting DNA duplex. Kinetic analyses of the conductance changes successfully resolved the elementary processes, which involve not only the ssDNA strands and their duplex but also partially hybridized intermediate strands, and we found an increase in the hybridization efficiency with increasing the concentration of DNA in contrast to the knowledge obtained previously by conventional ensemble measurements. The rate constants derived from our single-molecule studies provide a rational explanation of these findings, such as the suppression of DNA melting on surfaces with higher DNA coverage. The present methodology, which relies on intermolecular conductance measurements, can be extended to a range of single-molecule reactions and to the exploration of novel chemical syntheses. Hybridization of a single DNA molecule on a surface was investigated by electrical conductance measurements. The hybridization efficiency increases with increasing the DNA concentration, in contrast to preceding studies with ensemble studies.![]()
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Affiliation(s)
- Takanori Harashima
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-11 Ookayama Meguro-ku Tokyo 152-8551 Japan
| | - Yusuke Hasegawa
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-11 Ookayama Meguro-ku Tokyo 152-8551 Japan
| | - Satoshi Kaneko
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-11 Ookayama Meguro-ku Tokyo 152-8551 Japan
| | - Yuki Jono
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-11 Ookayama Meguro-ku Tokyo 152-8551 Japan
| | - Shintaro Fujii
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-11 Ookayama Meguro-ku Tokyo 152-8551 Japan
| | - Manabu Kiguchi
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-11 Ookayama Meguro-ku Tokyo 152-8551 Japan
| | - Tomoaki Nishino
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-11 Ookayama Meguro-ku Tokyo 152-8551 Japan
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23
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Dubini RCA, Schön A, Müller M, Carell T, Rovó P. Impact of 5-formylcytosine on the melting kinetics of DNA by 1H NMR chemical exchange. Nucleic Acids Res 2020; 48:8796-8807. [PMID: 32652019 PMCID: PMC7470965 DOI: 10.1093/nar/gkaa589] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/24/2020] [Accepted: 07/02/2020] [Indexed: 12/23/2022] Open
Abstract
5-Formylcytosine (5fC) is a chemically edited, naturally occurring nucleobase which appears in the context of modified DNA strands. The understanding of the impact of 5fC on dsDNA physical properties is to date limited. In this work, we applied temperature-dependent 1H Chemical Exchange Saturation Transfer (CEST) NMR experiments to non-invasively and site-specifically measure the thermodynamic and kinetic influence of formylated cytosine nucleobase on the melting process involving dsDNA. Incorporation of 5fC within symmetrically positioned CpG sites destabilizes the whole dsDNA structure-as witnessed from the ∼2°C decrease in the melting temperature and 5-10 kJ mol-1 decrease in ΔG°-and affects the kinetic rates of association and dissociation. We observed an up to ∼5-fold enhancement of the dsDNA dissociation and an up to ∼3-fold reduction in ssDNA association rate constants, over multiple temperatures and for several proton reporters. Eyring and van't Hoff analysis proved that the destabilization is not localized, instead all base-pairs are affected and the transition states resembles the single-stranded conformation. These results advance our knowledge about the role of 5fC as a semi-permanent epigenetic modification and assist in the understanding of its interactions with reader proteins.
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Affiliation(s)
- Romeo C A Dubini
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
- Center for Nanoscience (CeNS), Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799 Munich, Germany
| | - Alexander Schön
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Markus Müller
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Thomas Carell
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Petra Rovó
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
- Center for Nanoscience (CeNS), Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799 Munich, Germany
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24
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Kurus NN, Dultsev FN, Golyshev VM, Nekrasov DV, Pyshnyi DV, Lomzov AA. A QCM-based rupture event scanning technique as a simple and reliable approach to study the kinetics of DNA duplex dissociation. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:3771-3777. [PMID: 32716423 DOI: 10.1039/d0ay00613k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Rupture Event Scanning (REVS) is applied for the first time within an approach based on dynamic force spectroscopy. Using model DNA duplexes containing 20 pairs of oligonucleotides including those containing single mismatches, we demonstrated the possibility of reliable determination of the kinetic parameters of dissociation of biomolecular complexes: barrier positions, the rate constants of dissociation, and the lifetime of complexes. Within this approach, mechanical dissociation of DNA duplexes occurs according to a mechanism similar to unzipping. It is shown that this process takes place by overcoming a single energy barrier. In the case where a mismatch is located at the farthest duplex end from the QCM surface, a substantial decrease in the position of the barrier between the bound and unbound states is observed. We suppose that this is due to the formation of an initiation complex containing 3-4 pairs of bases, and this is sufficient for starting duplex unzipping.
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Affiliation(s)
- N N Kurus
- Rzhanov Institute of Semiconductor Physics SB, RAS, 630090, Russia.
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25
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Li S, Li P, Ge M, Wang H, Cheng Y, Li G, Huang Q, He H, Cao C, Lin D, Yang L. Elucidation of leak-resistance DNA hybridization chain reaction with universality and extensibility. Nucleic Acids Res 2020; 48:2220-2231. [PMID: 32020194 PMCID: PMC7049695 DOI: 10.1093/nar/gkaa016] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 12/30/2019] [Accepted: 01/23/2020] [Indexed: 12/14/2022] Open
Abstract
Hybridization chain reaction (HCR) was a significant discovery for the development of nanoscale materials and devices. One key challenge for HCR is the vulnerability to background leakage in the absence of the initiator. Here, we systematically analyze the sources of leakage and refine leak-resistant rule by using molecular thermodynamics and dynamics, biochemical and biophysical methods. Transient melting of DNA hairpin is revealed to be the underlying cause of leakage and that this can be mitigated through careful consideration of the sequence thermodynamics. The transition threshold of the energy barrier is proposed as a testing benchmark of leak-resistance DNA hairpins. The universal design of DNA hairpins is illustrated by the analysis of hsa-miR-21-5p as biomarker when used in conjunction with surface-enhanced Raman spectroscopy. We further extend the strategy for specific signal amplification of miRNA homologs. Significantly, it possibly provides a practical route to improve the accuracy of DNA self-assembly for signal amplification, and that could facilitate the development of sensors for the sensitive detection of interest molecules in biotechnology and clinical medicine.
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Affiliation(s)
- Shaofei Li
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.,School of Life Science, Anhui University, Hefei, Anhui 230601, China.,Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Pan Li
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Meihong Ge
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.,Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hongzhi Wang
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.,Cancer Hospital, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yizhuang Cheng
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.,Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Gan Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Qiang Huang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Huan He
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Chentai Cao
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.,Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Dongyue Lin
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.,Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Liangbao Yang
- Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.,Cancer Hospital, Chinese Academy of Sciences, Hefei, Anhui 230031, China
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26
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Ashwood B, Sanstead PJ, Dai Q, He C, Tokmakoff A. 5-Carboxylcytosine and Cytosine Protonation Distinctly Alter the Stability and Dehybridization Dynamics of the DNA Duplex. J Phys Chem B 2020; 124:627-640. [PMID: 31873021 DOI: 10.1021/acs.jpcb.9b11510] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Applications associated with nucleobase protonation events are grounded in their fundamental impact on DNA thermodynamics, structure, and hybridization dynamics. Of the canonical nucleobases, N3 protonation of cytosine (C) is the most widely utilized in both biology and nanotechnology. Naturally occurring C derivatives that shift the N3 pKa introduce an additional level of tunability. The epigenetic nucleobase 5-carboxylcytosine (caC) presents a particularly interesting example since this derivative forms Watson-Crick base pairs of similar stability and displays pH-dependent behavior over the same range as the canonical nucleobase. However, the titratable group in caC corresponds to the exocyclic carboxyl group rather than N3, and the implications of these divergent protonation events toward DNA hybridization thermodynamics, kinetics, and base pairing dynamics remain poorly understood. Here, we study the pH dependence of these physical properties using model oligonucleotides containing C and caC with FTIR and temperature-jump IR spectroscopy. We demonstrate that N3 protonation of C completely disrupts duplex stability, leading to large shifts in the duplex/single-strand equilibrium, a reduction in the cooperativity of melting, and an acceleration in the rate of duplex dissociation. In contrast, while increasing 5-carboxyl protonation in caC-containing duplexes induces an increase in base pair fluctuations, the DNA duplex can tolerate substantial protonation without significant perturbation to the duplex/single-strand equilibrium. However, 5-carboxyl protonation has a large impact on hybridization kinetics by reducing the transition state free energy. Our thermodynamic and kinetic analysis provides new insight on the impact of two divergent protonation mechanisms in naturally occurring nucleobases on the biophysical properties of DNA.
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