1
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Hennessy J, Klimkowski P, Singleton D, Gibney A, Coche M, Farrell NP, El-Sagheer AH, Brown T, Kellett A. Thiazole orange-carboplatin triplex-forming oligonucleotide (TFO) combination probes enhance targeted DNA crosslinking. RSC Med Chem 2024; 15:485-491. [PMID: 38389892 PMCID: PMC10880910 DOI: 10.1039/d3md00548h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 10/27/2023] [Indexed: 02/24/2024] Open
Abstract
We report a new class of carboplatin-TFO hybrid that incorporates a bifunctional alkyne-amine nucleobase monomer called AP-C3-dT that enables dual 'click' platinum(ii) drug conjugation and thiazole orange fluorophore coupling. Thiazole orange enhances the binding of Pt(ii)-TFO hybrids and provides an intrinsic method for monitoring triplex formation. These hybrid constructs possess increased stabilisation and crosslinking properties in comparison to earlier Pt(ii)-TFOs, and demonstrate sequence-specific binding at neutral pH.
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Affiliation(s)
- Joseph Hennessy
- SSPC, The Science Foundation Ireland Research Centre for Pharmaceuticals, School of Chemical Sciences, Dublin City University Glasnevin Dublin 9 Ireland
| | - Piotr Klimkowski
- Chemistry Research Laboratory, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Daniel Singleton
- ATDBio Ltd., School of Chemistry, University of Southampton Southampton SO17 1BJ UK
| | - Alex Gibney
- SSPC, The Science Foundation Ireland Research Centre for Pharmaceuticals, School of Chemical Sciences, Dublin City University Glasnevin Dublin 9 Ireland
| | - Malou Coche
- SSPC, The Science Foundation Ireland Research Centre for Pharmaceuticals, School of Chemical Sciences, Dublin City University Glasnevin Dublin 9 Ireland
| | - Nicholas P Farrell
- Department of Chemistry, Virginia Commonwealth University Richmond VA 23284-2006 USA
| | - Afaf H El-Sagheer
- Chemistry Research Laboratory, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
- School of Chemistry, University of Southampton Southampton SO17 1BJ UK
- Department of Science and Mathematics, Faculty of Petroleum and Mining, Engineering, Suez University Suez 43721 Egypt
| | - Tom Brown
- Chemistry Research Laboratory, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Andrew Kellett
- SSPC, The Science Foundation Ireland Research Centre for Pharmaceuticals, School of Chemical Sciences, Dublin City University Glasnevin Dublin 9 Ireland
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2
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Schöllkopf S, Knoll A, Homer A, Seitz O. Double FIT hybridization probes – towards enhancing brightness, turn-on and specificity of RNA detection. Chem Sci 2023; 14:4166-4173. [PMID: 37063796 PMCID: PMC10094420 DOI: 10.1039/d3sc00363a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/22/2023] [Indexed: 03/31/2023] Open
Abstract
Efficient fluorogenic hybridization probes combine high brightness and specificity of fluorescence signaling with large turn-on of fluorescence.
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Affiliation(s)
- Sophie Schöllkopf
- Institut für Chemie, Humboldt-Universität zu Berlin 12489 Berlin Germany
| | - Andrea Knoll
- Institut für Chemie, Humboldt-Universität zu Berlin 12489 Berlin Germany
| | - Amal Homer
- Institut für Chemie, Humboldt-Universität zu Berlin 12489 Berlin Germany
| | - Oliver Seitz
- Institut für Chemie, Humboldt-Universität zu Berlin 12489 Berlin Germany
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3
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Nucleic acid-based fluorescent sensor systems: a review. Polym J 2022. [DOI: 10.1038/s41428-022-00623-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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4
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Bai C, Klimkowski P, Jin C, Kuchlyan J, El-Sagheer AH, Brown T. A new phosphoramidite enables orthogonal double labelling to form combination oligonucleotide probes. Org Biomol Chem 2022; 20:8618-8622. [DOI: 10.1039/d2ob01899c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A novel phosphoramidite (AP-C3 dT) containing an alkyne and amine has been synthesized, enabling orthogonal labelling for combination oligonucleotides probes.
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Affiliation(s)
- Chunsen Bai
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Piotr Klimkowski
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Cheng Jin
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Jagannath Kuchlyan
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Afaf H. El-Sagheer
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
- Chemistry Branch, Department of Science and Mathematics, Faculty of Petroleum and Mining Engineering, Suez University, Suez 43721, Egypt
| | - Tom Brown
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
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5
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Takada T, Nishida K, Honda Y, Nakano A, Nakamura M, Fan S, Kawai K, Fujitsuka M, Yamana K. Stacked Thiazole Orange Dyes in DNA Capable of Switching Emissive Behavior in Response to Structural Transitions. Chembiochem 2021; 22:2729-2735. [PMID: 34191388 DOI: 10.1002/cbic.202100309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Indexed: 12/20/2022]
Abstract
Functional nucleic acids with the capability of generating fluorescence in response to hybridization events, microenvironment or structural changes are valuable as structural probes and chemical sensors. We now demonstrate the enzyme-assisted preparation of nucleic acids possessing multiple thiazole orange (TO) dyes and their fluorescent behavior, that show a spectral change from the typical monomer emission to the excimer-type red-shifted emission. We found that the fluorescent response and emission wavelength of the TO dyes were dependent on both the state of the DNA structure (single- or double-stranded DNA) and the arrangement of the TO dyes. We showed that the fluorescent behavior of the TO dyes can be applied for the detection of RNA molecules, suggesting that our approach for preparing the fluorescent nucleic acids functionalized with multiple TO dyes could be useful to design a fluorescence bioimaging and detection technique of biomolecules.
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Affiliation(s)
- Tadao Takada
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2280, Japan
| | - Koma Nishida
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2280, Japan
| | - Yurika Honda
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2280, Japan
| | - Aoi Nakano
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2280, Japan
| | - Mitsunobu Nakamura
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2280, Japan
| | - Shuya Fan
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka, 567-0047, Japan
| | - Kiyohiko Kawai
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka, 567-0047, Japan
| | - Mamoru Fujitsuka
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka, 567-0047, Japan
| | - Kazushige Yamana
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2280, Japan
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6
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Suss O, Motiei L, Margulies D. Broad Applications of Thiazole Orange in Fluorescent Sensing of Biomolecules and Ions. Molecules 2021; 26:2828. [PMID: 34068759 PMCID: PMC8126248 DOI: 10.3390/molecules26092828] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 04/26/2021] [Accepted: 04/27/2021] [Indexed: 12/13/2022] Open
Abstract
Fluorescent sensing of biomolecules has served as a revolutionary tool for studying and better understanding various biological systems. Therefore, it has become increasingly important to identify fluorescent building blocks that can be easily converted into sensing probes, which can detect specific targets with increasing sensitivity and accuracy. Over the past 30 years, thiazole orange (TO) has garnered great attention due to its low fluorescence background signal and remarkable 'turn-on' fluorescence response, being controlled only by its intramolecular torsional movement. These features have led to the development of numerous molecular probes that apply TO in order to sense a variety of biomolecules and metal ions. Here, we highlight the tremendous progress made in the field of TO-based sensors and demonstrate the different strategies that have enabled TO to evolve into a versatile dye for monitoring a collection of biomolecules.
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Affiliation(s)
| | | | - David Margulies
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel; (O.S.); (L.M.)
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7
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Gray MD, Deore PS, Chung AJ, Van Riesen AJ, Manderville RA, Prabhakar PS, Wetmore SD. Lighting Up the Thrombin-Binding Aptamer G-Quadruplex with an Internal Cyanine-Indole-Quinolinium Nucleobase Surrogate. Direct Fluorescent Intensity Readout for Thrombin Binding without Topology Switching. Bioconjug Chem 2020; 31:2596-2606. [PMID: 33156614 DOI: 10.1021/acs.bioconjchem.0c00530] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Fluorescent nucleobases represent an important class of molecular reporters of nucleic acid interactions. In this work, the advantages of utilizing a noncanonical fluorescent nucleobase surrogate for monitoring thrombin binding by the 15-mer thrombin binding aptamer (TBA) is presented. TBA folds into an antiparallel G-quadruplex (GQ) with loop thymidine (T) residues interacting directly with the protein in the thrombin-TBA complex. In the free GQ, T3 is solvent-exposed and does not form canonical base-pairs within the antiparallel GQ motif. Upon thrombin binding, T3 interacts directly with a hydrophobic protein binding pocket. Replacing T3 with a cyanine-indole-quinolinium (4QI) hemicyanine dye tethered to an acyclic 1,2-propanediol linker is shown to have minimal impact on GQ stability and structure with the internal 4QI displaying a 40-fold increase in emission intensity at 586 nm (excitation 508 nm) compared to the free dye in solution. Molecular dynamics (MD) simulations demonstrate that the 4QI label π-stacks with T4 and T13 within the antiparallel GQ fold, which is supported by strong energy transfer (ET) fluorescence from the GQ (donor) to the 4QI label (acceptor). Thrombin binding to 4QI-TBA diminishes π-stacking interactions between 4QI and the GQ structure to cause a turn-off emission intensity response with an apparent dissociation constant (Kd) of 650 nM and a limit of detection (LoD) of 150 nM. These features highlight the utility of internal noncanonical fluorescent surrogates for monitoring protein binding by GQ-folding aptamers in the absence of DNA topology switching.
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Affiliation(s)
- Micaela D Gray
- Department of Chemistry & Toxicology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Prashant S Deore
- Department of Chemistry & Toxicology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Andrew J Chung
- Department of Chemistry & Toxicology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Abigail J Van Riesen
- Department of Chemistry & Toxicology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Richard A Manderville
- Department of Chemistry & Toxicology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Preethi Seelam Prabhakar
- Department of Chemistry & Biochemistry, University of Lethbridge, Lethbridge, Alberta, Canada T1K 3M4
| | - Stacey D Wetmore
- Department of Chemistry & Biochemistry, University of Lethbridge, Lethbridge, Alberta, Canada T1K 3M4
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8
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Li Y, Zhou Y, Yue X, Dai Z. Cyanine Conjugate-Based Biomedical Imaging Probes. Adv Healthc Mater 2020; 9:e2001327. [PMID: 33000915 DOI: 10.1002/adhm.202001327] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/11/2020] [Indexed: 12/12/2022]
Abstract
Cyanine is a class of fluorescent dye with meritorious fluorescence properties and has motivated numerous researchers to explore its imaging capabilities by miscellaneous structural modification and functionalization strategies. The covalent conjugation with other functional molecules represents a distinctive design strategy and has shown immense potential in both basic and clinical research. This review article summarizes recent achievements in cyanine conjugate-based probes for biomedical imaging. Particular attention is paid to the conjugation with targeting warheads and other contrast agents for targeted fluorescence imaging and multimodal imaging, respectively. Additionally, their clinical potential in cancer diagnostics is highlighted and some concurrent impediments for clinical translation are discussed.
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Affiliation(s)
- Yang Li
- Department of Biomedical Engineering College of Engineering Peking University Beijing 100871 China
| | - Yiming Zhou
- Department of Biomedical Engineering College of Engineering Peking University Beijing 100871 China
| | - Xiuli Yue
- School of Environment Harbin Institute of Technology Harbin 150090 China
| | - Zhifei Dai
- Department of Biomedical Engineering College of Engineering Peking University Beijing 100871 China
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9
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Klimkowski P, De Ornellas S, Singleton D, El-Sagheer AH, Brown T. Design of thiazole orange oligonucleotide probes for detection of DNA and RNA by fluorescence and duplex melting. Org Biomol Chem 2019; 17:5943-5950. [PMID: 31157811 PMCID: PMC6686645 DOI: 10.1039/c9ob00885c] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We have synthesised a range of thiazole orange (TO) functionalised oligonucleotides for nucleic acid detection in which TO is attached to the nucleobase or sugar of thymidine. The properties of duplexes between TO-probes and their DNA and RNA targets strongly depend on the length of the linker between TO and the oligonucleotide, the position of attachment of TO to the nucleotide (major or minor groove) and the mode of attachment of thiazole orange (via benzothiazole or quinoline moiety). This information can be used to design probes for detection of target nucleic acids by fluorescence or duplex melting. With cellular imaging in mind we show that 2'-OMe RNA probes with TO at the 5-position of uracil or the 2'-position of the ribose sugar are particularly effective, exhibiting up to 44-fold fluorescence enhancement against DNA and RNA, and high duplex stability. Excellent mismatch discrimination is achieved when the mispaired base is located adjacent to the TO-modified nucleotide rather than opposite to it. The simple design, ease of synthesis and favourable properties of these TO probes suggest applications in fluorescent imaging of DNA and RNA in a cellular context.
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Affiliation(s)
- Piotr Klimkowski
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Sara De Ornellas
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK. and Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DS, UK
| | - Daniel Singleton
- ATDBio, School of Chemistry University of Southampton, SO17 1BJ, UK
| | - Afaf H El-Sagheer
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK. and Chemistry Branch, Department of Science and Mathematics, Faculty of Petroleum and Mining Engineering, Suez University, Suez 43721, Egypt
| | - Tom Brown
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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10
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Gaspar I, Hövelmann F, Chamiolo J, Ephrussi A, Seitz O. Quantitative mRNA Imaging with Dual Channel qFIT Probes to Monitor Distribution and Degree of Hybridization. ACS Chem Biol 2018; 13:742-749. [PMID: 29378392 DOI: 10.1021/acschembio.7b01007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Fluorogenic oligonucleotide probes facilitate the detection and localization of RNA targets within cells. However, quantitative measurements of mRNA abundance are difficult when fluorescence signaling is based on intensity changes because a high concentration of unbound probes cannot be distinguished from a low concentration of target-bound probes. Here, we introduce qFIT (quantitative forced intercalation) probes that allow the detection both of probe-target complexes and of unbound probes on separate, independent channels. A surrogate nucleobase based on thiazole orange (TO) probes the hybridization status. The second channel involves a nonresponsive near-IR dye, which serves as a reporter of concentration. We show that the undesirable perturbation of the hybridization reporter TO is avoided when the near-IR dye Cy7 is connected by means of short triazole linkages in an ≥18 nucleotides distance. We used the qFIT probes to localize and quantify oskar mRNA in fixed egg chambers of wild-type and mutant Drosophila melanogaster by wash-free fluorescence in situ hybridization. The measurements revealed a relative 400-fold enrichment of oskar within a 3000 μm3 large volume at the posterior pole of stage 8-9 oocytes, which peaked at a remarkably high 1.8 μM local concentration inside 0.075 μm3 volume units. We discuss detection limits and show that the number of oskar mRNA molecules per oocyte is independent of the oocyte size, which suggests that the final levels are attained already during the onset of oskar localization at stage 8.
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Affiliation(s)
- Imre Gaspar
- European Molecular Biology Laboratory (EMBL) Heidelberg, 69117 Heidelberg, Germany
| | - Felix Hövelmann
- Institut für Chemie der Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Jasmine Chamiolo
- Institut für Chemie der Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Anne Ephrussi
- European Molecular Biology Laboratory (EMBL) Heidelberg, 69117 Heidelberg, Germany
| | - Oliver Seitz
- Institut für Chemie der Humboldt-Universität zu Berlin, 12489 Berlin, Germany
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11
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Hwang GT. Single-Labeled Oligonucleotides Showing Fluorescence Changes Upon Hybridization with Target Nucleic Acids. Molecules 2018; 23:E124. [PMID: 29316733 PMCID: PMC6017082 DOI: 10.3390/molecules23010124] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 01/05/2018] [Accepted: 01/08/2018] [Indexed: 12/12/2022] Open
Abstract
Sequence-specific detection of nucleic acids has been intensively studied in the field of molecular diagnostics. In particular, the detection and analysis of single-nucleotide polymorphisms (SNPs) is crucial for the identification of disease-causing genes and diagnosis of diseases. Sequence-specific hybridization probes, such as molecular beacons bearing the fluorophore and quencher at both ends of the stem, have been developed to enable DNA mutation detection. Interestingly, DNA mutations can be detected using fluorescently labeled oligonucleotide probes with only one fluorophore. This review summarizes recent research on single-labeled oligonucleotide probes that exhibit fluorescence changes after encountering target nucleic acids, such as guanine-quenching probes, cyanine-containing probes, probes containing a fluorophore-labeled base, and microenvironment-sensitive probes.
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Affiliation(s)
- Gil Tae Hwang
- Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 41566, Korea.
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12
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Nim-Anussornkul D, Vilaivan T. Synthesis and optical properties of pyrrolidinyl peptide nucleic acid bearing a base discriminating fluorescence nucleobase 8-(pyrene-1-yl)-ethynyladenine. Bioorg Med Chem 2017; 25:6388-6397. [PMID: 29111370 DOI: 10.1016/j.bmc.2017.10.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 10/06/2017] [Accepted: 10/12/2017] [Indexed: 12/29/2022]
Abstract
A combination of fluorophore and nucleobase through a π-conjugated rigid linker integrates the base pairing and the fluorescence change into a single event. Such base discriminating fluorophore can change its fluorescence as a direct response to the base pairing event and therefore have advantages over tethered labels or base surrogates lacking the hydrogen-bonding ability. 8-(Pyrene-1-yl)ethynyl-adenine (APyE) has been extensively used as fluorescence labels in DNA and LNA, but it showed little discrimination between different nucleobases. Herein we investigated the synthesis, base pairing ability and optical properties of APyE in pyrrolidinyl peptide nucleic acid - a DNA mimic that shows much stronger affinity and specificity towards DNA than natural oligonucleotides. The APyE in PNA pairs specifically with thymine in the DNA strand, and resulted in 1.5-5.2-fold enhanced and blue-shifted fluorescence emission. Fluorescence quenching was observed in the presence of mismatched base or abasic site directly opposite to the APyE. The behavior of APyE in acpcPNA is distinctively different from DNA whereby a fluorescence was increased selectively upon duplex formation with complementary DNA and therefore emphasizing the unique advantages of using PNA as alternative oligonucleotide probes. Applications as color-shifting probe for detection of trinucleotide repeats in DNA were demonstrated, and the performance of the probe was further improved by combination with reduced graphene oxide as an external nanoquencher.
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Affiliation(s)
- Duangrat Nim-Anussornkul
- Organic Synthesis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Patumwan, Bangkok 10330, Thailand
| | - Tirayut Vilaivan
- Organic Synthesis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Patumwan, Bangkok 10330, Thailand.
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13
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van Gijtenbeek LA, Kok J. Illuminating Messengers: An Update and Outlook on RNA Visualization in Bacteria. Front Microbiol 2017; 8:1161. [PMID: 28690601 PMCID: PMC5479882 DOI: 10.3389/fmicb.2017.01161] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 06/07/2017] [Indexed: 01/04/2023] Open
Abstract
To be able to visualize the abundance and spatiotemporal features of RNAs in bacterial cells would permit obtaining a pivotal understanding of many mechanisms underlying bacterial cell biology. The first methods that allowed observing single mRNA molecules in individual cells were introduced by Bertrand et al. (1998) and Femino et al. (1998). Since then, a plethora of techniques to image RNA molecules with the aid of fluorescence microscopy has emerged. Many of these approaches are useful for the large eukaryotic cells but their adaptation to study RNA, specifically mRNA molecules, in bacterial cells progressed relatively slow. Here, an overview will be given of fluorescent techniques that can be used to reveal specific RNA molecules inside fixed and living single bacterial cells. It includes a critical evaluation of their caveats as well as potential solutions.
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Affiliation(s)
- Lieke A van Gijtenbeek
- Department of Molecular Genetics, Faculty of Science and Engineering, University of GroningenGroningen, Netherlands
| | - Jan Kok
- Department of Molecular Genetics, Faculty of Science and Engineering, University of GroningenGroningen, Netherlands
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14
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Lee JW, Son YS, Hwang JY, Park Y, Hwang GT. pH-Responsive quencher-free molecular beacon systems containing 2′-deoxyuridine units labeled with fluorene derivatives. Org Biomol Chem 2017; 15:7165-7172. [DOI: 10.1039/c7ob01703k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
pH-Responsive oligodeoxynucleotides only exhibited dramatic increases in fluorescence upon duplex formation with their fully matched target DNAs.
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Affiliation(s)
- Ji Won Lee
- Department of Chemistry
- Kyungpook National University
- Daegu 41566
- Republic of Korea
| | - Ye-Seul Son
- Department of Chemistry
- Kyungpook National University
- Daegu 41566
- Republic of Korea
| | - Jun Yeon Hwang
- Department of Chemistry
- Kyungpook National University
- Daegu 41566
- Republic of Korea
| | - Yoojin Park
- Department of Chemistry
- Division of Advanced Materials Science
- Pohang University of Science and Technology
- Pohang 37673
- Republic of Korea
| | - Gil Tae Hwang
- Department of Chemistry
- Kyungpook National University
- Daegu 41566
- Republic of Korea
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15
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Fang GM, Seitz O. Bivalent Display of Dicysteine on Peptide Nucleic Acids for Homogenous DNA/RNA Detection through in Situ Fluorescence Labelling. Chembiochem 2016; 18:189-194. [PMID: 27883258 DOI: 10.1002/cbic.201600623] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Indexed: 01/06/2023]
Abstract
Fluorogenic probes that signal the presence of specific DNA or RNA sequences are key enabling tools for molecular disease diagnosis and imaging studies. Usually, at least one fluorophore is attached through covalent bonding to an oligonucleotide probe. However, the additional conjugation step increases costs. Here we introduce a method that avoids the requirement for the preparation of fluorescence-labelled oligonucleotides and provides the opportunity to alter the fluorogenic reporter dye without resynthesis. The method is based on adjacent hybridization of two dicysteine-containing peptide nucleic acid (PNA) probes to form a bipartite tetracysteine motif that binds profluorescent bisarsenical dyes such as FIAsH, ReAsH or CrAsH. Binding is accompanied by strong increases in fluorescence emission (with response factors of up to 80-fold and high brightness up to 50 mL mol-1 cm-1 ). The detection system provides sub-nanomolar limits of detection and allows discrimination of single nucleotide variations through more than 20-fold changes in fluorescence intensity. To demonstrate its usefulness, the FIAsH-based readout of the bivalent CysCys-PNA display was interfaced with a rolling-circle amplification (RCA) assay used to detect disease-associated microRNA let-7a.
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Affiliation(s)
- Ge-Min Fang
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489, Berlin, Germany
| | - Oliver Seitz
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489, Berlin, Germany
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16
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Murayama K, Asanuma H. Effect of Methyl Group on Acyclic Serinol Scaffold for Tethering Dyes on the DNA Duplex Stability. Chembiochem 2016; 18:142-149. [DOI: 10.1002/cbic.201600558] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Indexed: 12/19/2022]
Affiliation(s)
- Keiji Murayama
- Graduate School of Engineering; Nagoya University; Furo-cho Chikusa-ku Nagoya 464-8603 Japan
| | - Hiroyuki Asanuma
- Graduate School of Engineering; Nagoya University; Furo-cho Chikusa-ku Nagoya 464-8603 Japan
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17
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Fluorescent Oligonucleotides Containing a 2-Ethynylfluorene- or 2-Ethynylfluorenone-labeled 2′-Deoxyguanosine Unit: Fluorescence Changes upon Duplex Formation. B KOREAN CHEM SOC 2016. [DOI: 10.1002/bkcs.10856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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18
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Kashida H, Morimoto K, Asanuma H. A stem-less probe using spontaneous pairing between Cy3 and quencher for RNA detection. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2016; 17:267-273. [PMID: 27877879 PMCID: PMC5101869 DOI: 10.1080/14686996.2016.1182412] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 03/30/2016] [Accepted: 04/05/2016] [Indexed: 05/26/2023]
Abstract
We herein report a stem-less probe for the detection of RNA that depends on pairing between Cy3 and nitro methyl red. In our design, two Cy3 residues and two nitro methyl red residues were introduced into an oligonucleotide. In the absence of the target, these dyes formed a complex, and emission of Cy3 was efficiently quenched. Hybridization with the target RNA disrupted this interaction and resulted in Cy3 emission. Under optimized conditions, the signal to background ratio was as high as 180. We demonstrated specific detection of target RNA in cells using a wash-free FISH protocol.
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Affiliation(s)
- Hiromu Kashida
- Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya464-8603, Japan
- Japan Science and Technology Agency, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama332-0012, Japan
| | - Kazuhiro Morimoto
- Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya464-8603, Japan
| | - Hiroyuki Asanuma
- Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya464-8603, Japan
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19
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Hövelmann F, Seitz O. DNA Stains as Surrogate Nucleobases in Fluorogenic Hybridization Probes. Acc Chem Res 2016; 49:714-23. [PMID: 26963493 DOI: 10.1021/acs.accounts.5b00546] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The increasing importance assigned to RNA dynamics in cells and tissues calls for probe molecules that enable fluorescence microscopy imaging in live cells. To achieve this goal, fluorescence dyes are conjugated with oligonucleotides so as to provide strong emission upon hybridization with the target molecule. The impressive 10(3)-fold fluorescence intensification observed when DNA stains such as thiazole orange (TO) interact with double-stranded DNA is intriguing and prompted the exploration of oligonucleotide conjugates. However, nonspecific interactions of DNA stains with polynucleotides tend to increase background, which would affect the contrast achievable in live-cell imaging. This Account describes the development of DNA-stain-labeled hybridization probes that provide high signal-to-background. We focus on our contributions in context with related advances from other laboratories. The emphasis will be on the requirements of RNA imaging in live cells. To reduce background, intercalator dyes such as TO were appended to peptide nucleic acid (PNA), which is less avidly recognized by DNA stains than DNA/RNA. Constraining the TO dye as a nucleobase surrogate in "forced intercalation (FIT) probes" improved the target specificity, presumably by helping to prevent unspecific interactions. The enforcement of TO intercalation between predetermined base pairs upon formation of the probe-target duplex provided for high brightness and enabled match/mismatch selectivity beyond stringency of hybridization. We show examples that highlight the use of PNA FIT probes in the imaging of mRNA, miRNA, and lncRNA in living cells. The "FIT approach" was recently extended to DNA probes. Signal brightness can become limiting when low-abundance targets ought to be visualized over cellular autofluorescence. We discuss strategies that further the brightness of signaling by FIT probes. Multilabeling with identical dyes does not solve the brightness issue. To avoid self-quenching, we combined two different yet spectrally overlapping fluorescent base surrogates. A hybridization-sensitive dye serves as a light collector that transfers energy to a brightly emissive acceptor dye. To improve the brilliance of single-dye probes, the "TO-nucleotide" was accompanied by an adjacent locked nucleic acid (LNA) unit. The LNA-constrained FIT probes are responsive and bright, enabling the tracking of mRNA transport in living tissue. We also show that the color repertoire of FIT probes is not restricted to the green-emissive TO but can be expanded to cyan and red. A new base surrogate (4,4-linked bisquinoline) provided up to 195-fold enhancement of the fluorescence.
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Affiliation(s)
- Felix Hövelmann
- Department of Chemistry, Humboldt University Berlin, Brook-Taylor-Str.
2, 12489 Berlin, Germany
| | - Oliver Seitz
- Department of Chemistry, Humboldt University Berlin, Brook-Taylor-Str.
2, 12489 Berlin, Germany
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20
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Berndl S, Dimitrov SD, Menacher F, Fiebig T, Wagenknecht HA. Thiazole Orange Dimers in DNA: Fluorescent Base Substitutions with Hybridization Readout. Chemistry 2016; 22:2386-95. [DOI: 10.1002/chem.201503849] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Indexed: 01/03/2023]
Affiliation(s)
- Sina Berndl
- Institute of Organic Chemistry; Karlsruhe Institute of Technology (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
- Institute of Organic Chemistry; University of Regensburg; 93040 Regensburg Germany
| | - Stoichko D. Dimitrov
- Centre for Plastic Electronics; Department of Chemistry; Imperial College London; Exhibition Road London SW7 2AZ UK
| | - Florian Menacher
- Institute of Organic Chemistry; Karlsruhe Institute of Technology (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
- Institute of Organic Chemistry; University of Regensburg; 93040 Regensburg Germany
| | - Torsten Fiebig
- Feinberg School of Medicine; Department of Otolaryngology; Northwestern University; 420 East Superior Street Chicago IL 60611 USA
| | - Hans-Achim Wagenknecht
- Institute of Organic Chemistry; Karlsruhe Institute of Technology (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
- Institute of Organic Chemistry; University of Regensburg; 93040 Regensburg Germany
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21
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Hövelmann F, Gaspar I, Chamiolo J, Kasper M, Steffen J, Ephrussi A, Seitz O. LNA-enhanced DNA FIT-probes for multicolour RNA imaging. Chem Sci 2016; 7:128-135. [PMID: 29861973 PMCID: PMC5950760 DOI: 10.1039/c5sc03053f] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 11/01/2015] [Indexed: 01/04/2023] Open
Abstract
The simultaneous imaging of different RNA molecules in homogeneous solution is a challenge and requires optimisation to enable unambiguous staining of intracellular RNA targets. Our approach relies on single dye forced intercalation (FIT) probes, in which a visco-sensitive reporter of the thiazole orange (TO) family serves as a surrogate nucleobase and provides enhancements of fluorescence upon hybridisation. Previous FIT probes spanned the cyan and green emission range. Herein, we report for the first time chromophores for FIT probes that emit in the red range (above 600 nm). Such probes are valuable to overcome cellular auto-fluorescent background and enable multiplexed detection. In order to find suitable chromophores, we developed a submonomer approach that facilitated the rapid analysis of different TO family dyes in varied sequence positions. A carboxymethylated 4,4'-methine linked cyanine, which we named quinoline blue (QB), provided exceptional response characteristics at the 605 nm emission maximum. Exceeding previously reported base surrogates, the emission of the QB nucleotide intensified by up to 195-fold upon binding of complementary RNA. Owing to large extinction coefficients and quantum yields (up to ε = 129.000 L mol-1 cm-1 and Φ = 0.47, respectively) QB-FIT probes enable imaging of intracellular mRNA. A mixture of BO-, TO- and QB-containing FIT probes allowed the simultaneous detection of three different RNA targets in homogenous solution. TO- and QB-FIT probes were used to localize oskar mRNA and other polyadenylated mRNA molecules in developing oocytes from Drosphila melanogaster by means of wash-free fluorescent in situ hybridisation and super resolution microscopy (STED).
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Affiliation(s)
- F Hövelmann
- Department of Chemistry , Humboldt University Berlin , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany .
- European Molecular Biology Laboratory (EMBL) Heidelberg , Meyerhofstr. 1 , 69117 Heidelberg , Germany
| | - I Gaspar
- European Molecular Biology Laboratory (EMBL) Heidelberg , Meyerhofstr. 1 , 69117 Heidelberg , Germany
| | - J Chamiolo
- Department of Chemistry , Humboldt University Berlin , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany .
| | - M Kasper
- Department of Chemistry , Humboldt University Berlin , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany .
| | - J Steffen
- Department of Chemistry , Humboldt University Berlin , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany .
| | - A Ephrussi
- European Molecular Biology Laboratory (EMBL) Heidelberg , Meyerhofstr. 1 , 69117 Heidelberg , Germany
| | - O Seitz
- Department of Chemistry , Humboldt University Berlin , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany .
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22
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Barrois S, Wörner S, Wagenknecht HA. The role of duplex stability for wavelength-shifting fluorescent DNA probes: energy transfer vs. exciton interactions in DNA "traffic lights". Photochem Photobiol Sci 2015; 13:1126-9. [PMID: 25000916 DOI: 10.1039/c4pp00153b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Exciton interactions between thiazole orange and thiazole red as nucleotide substitutes in DNA hairpins interfere with efficient energy transfer and fluorescence color change as readout. This interference can be tuned by two structural parameters that control the hairpin duplex stability.
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Affiliation(s)
- Sebastian Barrois
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.
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23
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Asanuma H, Akahane M, Niwa R, Kashida H, Kamiya Y. Highly Sensitive and Robust Linear Probe for Detection of mRNA in Cells. Angew Chem Int Ed Engl 2015; 54:4315-9. [DOI: 10.1002/anie.201411000] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 12/22/2014] [Indexed: 12/16/2022]
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24
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Asanuma H, Akahane M, Niwa R, Kashida H, Kamiya Y. Highly Sensitive and Robust Linear Probe for Detection of mRNA in Cells. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201411000] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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25
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Asanuma H, Kashida H, Kamiya Y. De novo design of functional oligonucleotides with acyclic scaffolds. CHEM REC 2014; 14:1055-69. [PMID: 25171046 DOI: 10.1002/tcr.201402040] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Indexed: 01/20/2023]
Abstract
In this account, we demonstrate a new methodology for the de novo design of functional oligonucleotides with the acyclic scaffolds threoninol and serinol. Four functional motifs-wedge, interstrand-wedge, dimer, and cluster-have been prepared from natural DNA or RNA and functional base surrogates prepared from d-threoninol. The following applications of these motifs are described: (1) photoregulation of formation and dissociation of a DNA duplex modified with azobenzene, (2) sequence-specific detection of DNA using a fluorescent probe, (3) formation of fluorophore assemblies that mimic quantum dots, (4) improved strand selectivity of siRNA modified with a base surrogate, and (5) in vivo tracing of the RNAi pathway. Finally, we introduce artificial nucleic acids (XNAs) prepared from d-threoninol and serinol functionalized with each of the four nucleobases, which have unique properties compared with other acyclic XNAs. Functional oligonucleotides designed from acyclic scaffolds will be powerful tools for both DNA nanotechnology and biotechnology.
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Affiliation(s)
- Hiroyuki Asanuma
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan.
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26
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Hövelmann F, Gaspar I, Loibl S, Ermilov EA, Röder B, Wengel J, Ephrussi A, Seitz O. Brightness through local constraint--LNA-enhanced FIT hybridization probes for in vivo ribonucleotide particle tracking. Angew Chem Int Ed Engl 2014; 53:11370-5. [PMID: 25167966 DOI: 10.1002/anie.201406022] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Indexed: 11/11/2022]
Abstract
Imaging the dynamics of RNA in living cells is usually performed by means of transgenic approaches that require modification of RNA targets and cells. Fluorogenic hybridization probes would also allow the analysis of wild-type organisms. We developed nuclease-resistant DNA forced intercalation (FIT) probes that combine the high enhancement of fluorescence upon hybridization with the high brightness required to allow tracking of individual ribonucleotide particles (RNPs). In our design, a single thiazole orange (TO) intercalator dye is linked as a nucleobase surrogate and an adjacent locked nucleic acid (LNA) unit serves to introduce a local constraint. This closes fluorescence decay channels and thereby increases the brightness of the probe-target duplexes. As few as two probes were sufficient to enable the tracking of oskar mRNPs in wild-type living Drosophila melanogaster oocytes.
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Affiliation(s)
- Felix Hövelmann
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin (Germany)
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27
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Hövelmann F, Gaspar I, Loibl S, Ermilov EA, Röder B, Wengel J, Ephrussi A, Seitz O. Helligkeit durch lokale Rigidifizierung - LNA-verstärkte FIT-Sonden zur bildgebenden Darstellung von Ribonukleotidpartikeln in vivo. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201406022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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28
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Bohländer PR, Wagenknecht HA. Synthesis and evaluation of cyanine-styryl dyes with enhanced photostability for fluorescent DNA staining. Org Biomol Chem 2014; 11:7458-62. [PMID: 24088963 DOI: 10.1039/c3ob41717d] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The photostability of cyanine-styryl dyes of the indole-quinolinium type can be significantly improved by structural variations while the excellent optical properties including the bright fluorescence in the presence of DNA can be maintained or even improved, too.
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Affiliation(s)
- Peggy R Bohländer
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.
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29
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Kovaliov M, Segal M, Kafri P, Yavin E, Shav-Tal Y, Fischer B. Detection of cyclin D1 mRNA by hybridization sensitive NIC-oligonucleotide probe. Bioorg Med Chem 2014; 22:2613-21. [PMID: 24726303 DOI: 10.1016/j.bmc.2014.03.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 03/18/2014] [Accepted: 03/20/2014] [Indexed: 12/20/2022]
Abstract
A large group of fluorescent hybridization probes, includes intercalating dyes for example thiazole orange (TO). Usually TO is coupled to nucleic acids post-synthetically which severely limits its use. Here, we have developed a phosphoramidite monomer, 10, and prepared a 2'-OMe-RNA probe, labeled with 5-(trans-N-hexen-1-yl-)-TO-2'-deoxy-uridine nucleoside, dU(TO), (Nucleoside bearing an Inter-Calating moiety, NIC), for selective mRNA detection. We investigated a series of 15-mer 2'-OMe-RNA probes, targeting the cyclin D1 mRNA, containing one or several dU(TO) at various positions. dU(TO)-2'-OMe-RNA exhibited up to 7-fold enhancement of TO emission intensity upon hybridization with the complementary RNA versus that of the oligomer alone. This NIC-probe was applied for the specific detection of a very small amount of a breast cancer marker, cyclin D1 mRNA, in total RNA extract from cancerous cells (250 ng/μl). Furthermore, this NIC-probe was found to be superior to our related NIF (Nucleoside with Intrinsic Fluorescence)-probe which could detect cyclin D1 mRNA target only at high concentrations (1840 ng/μl). Additionally, dU(T) can be used as a monomer in solid-phase oligonucleotide synthesis, thus avoiding the need for post-synthetic modification of oligonucleotide probes. Hence, we propose dU(TO) oligonucleotides, as hybridization probes for the detection of specific RNA in homogeneous solutions and for the diagnosis of breast cancer.
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Affiliation(s)
- Marina Kovaliov
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Meirav Segal
- School of Pharmacy, Institute for Drug Research, The Hebrew University of Jerusalem, Ein Karem, Jerusalem 91120, Israel
| | - Pinhas Kafri
- Faculty of Life Sciences and Institute of Nanotechnology, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Eylon Yavin
- School of Pharmacy, Institute for Drug Research, The Hebrew University of Jerusalem, Ein Karem, Jerusalem 91120, Israel
| | - Yaron Shav-Tal
- Faculty of Life Sciences and Institute of Nanotechnology, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Bilha Fischer
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel.
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30
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Boutorine AS, Novopashina DS, Krasheninina OA, Nozeret K, Venyaminova AG. Fluorescent probes for nucleic Acid visualization in fixed and live cells. Molecules 2013; 18:15357-97. [PMID: 24335616 PMCID: PMC6270009 DOI: 10.3390/molecules181215357] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/20/2013] [Accepted: 12/05/2013] [Indexed: 12/13/2022] Open
Abstract
This review analyses the literature concerning non-fluorescent and fluorescent probes for nucleic acid imaging in fixed and living cells from the point of view of their suitability for imaging intracellular native RNA and DNA. Attention is mainly paid to fluorescent probes for fluorescence microscopy imaging. Requirements for the target-binding part and the fluorophore making up the probe are formulated. In the case of native double-stranded DNA, structure-specific and sequence-specific probes are discussed. Among the latest, three classes of dsDNA-targeting molecules are described: (i) sequence-specific peptides and proteins; (ii) triplex-forming oligonucleotides and (iii) polyamide oligo(N-methylpyrrole/N-methylimidazole) minor groove binders. Polyamides seem to be the most promising targeting agents for fluorescent probe design, however, some technical problems remain to be solved, such as the relatively low sequence specificity and the high background fluorescence inside the cells. Several examples of fluorescent probe applications for DNA imaging in fixed and living cells are cited. In the case of intracellular RNA, only modified oligonucleotides can provide such sequence-specific imaging. Several approaches for designing fluorescent probes are considered: linear fluorescent probes based on modified oligonucleotide analogs, molecular beacons, binary fluorescent probes and template-directed reactions with fluorescence probe formation, FRET donor-acceptor pairs, pyrene excimers, aptamers and others. The suitability of all these methods for living cell applications is discussed.
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Affiliation(s)
- Alexandre S. Boutorine
- Muséum National d’Histoire Naturelle, CNRS, UMR 7196, INSERM, U565, 57 rue Cuvier, B.P. 26, Paris Cedex 05, F-75231, France; E-Mail:
| | - Darya S. Novopashina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Division of Russian Academy of Sciences, Lavrentyev Ave., 8, Novosibirsk 630090, Russia; E-Mails: (D.S.N.); (O.A.K.); (A.G.V.)
| | - Olga A. Krasheninina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Division of Russian Academy of Sciences, Lavrentyev Ave., 8, Novosibirsk 630090, Russia; E-Mails: (D.S.N.); (O.A.K.); (A.G.V.)
- Department of Natural Sciences, Novosibirsk State University, Pirogova Str., 2, Novosibirsk 630090, Russia
| | - Karine Nozeret
- Muséum National d’Histoire Naturelle, CNRS, UMR 7196, INSERM, U565, 57 rue Cuvier, B.P. 26, Paris Cedex 05, F-75231, France; E-Mail:
| | - Alya G. Venyaminova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Division of Russian Academy of Sciences, Lavrentyev Ave., 8, Novosibirsk 630090, Russia; E-Mails: (D.S.N.); (O.A.K.); (A.G.V.)
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Hövelmann F, Gaspar I, Ephrussi A, Seitz O. Brightness enhanced DNA FIT-probes for wash-free RNA imaging in tissue. J Am Chem Soc 2013; 135:19025-32. [PMID: 24295172 DOI: 10.1021/ja410674h] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Fluorogenic oligonucleotides enable RNA imaging in cells and tissues. A high responsiveness of fluorescence is required when unbound probes cannot be washed away. Furthermore, emission should be bright in order to enable detection against autofluorescent background. The development of fluorescence-quenched hybridization probes has led to remarkable improvement of fluorescence responsiveness. Yet, comparably little attention has been paid to the brightness of smart probes. We describe hybridization probes that combine responsiveness with a high brightness of the measured signal. The method relies upon quencher-free DNA forced intercalation (FIT)-probes, in which two (or more) intercalator dyes of the thiazole orange (TO) family serve as nucleobase surrogates. Initial experiments on multi-TO-labeled probes led to improvements of responsiveness, but self-quenching limited their brightness. To enhance both brightness and responsiveness the highly responsive TO nucleoside was combined with the highly emissive oxazolopyridine analogue JO. Single-stranded TO/JO FIT-probes are dark. In the probe-target duplex, quenching caused by torsional twisting and dye-dye contact is prevented. The TO nucleoside appears to serve as a light collector that increases the extinction coefficient and transfers excitation energy to the JO emitter. This leads to very bright JO emission upon hybridization (F/F0 = 23, brightness = 43 mL mol(-1) cm(-1) at λex = 516 nm). TO/JO FIT-probes allowed the direct fluorescence microscopic imaging of oskar mRNA within a complex tissue. Of note, RNA imaging was feasible under wide-field excitation conditions. The described protocol enables rapid RNA imaging in tissue without the need for cutting-edge equipment, time-consuming washing, or signal amplification.
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Affiliation(s)
- Felix Hövelmann
- Institut für Chemie der Humboldt-Universität zu Berlin , 12489 Berlin, Germany
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32
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Lee J, Cho HY, Hwang GT. Highly efficient quencher-free molecular beacon systems containing 2-ethynyldibenzofuran- and 2-ethynyldibenzothiophene-labeled 2'-deoxyuridine units. Chembiochem 2013; 14:1353-62. [PMID: 23824637 DOI: 10.1002/cbic.201300240] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Indexed: 12/21/2022]
Abstract
We have prepared two fluorescent DNA probes--UDBF and UDBT, containing 2-ethynyldibenzofuran and 2-ethynyldibenzothiophene moieties, respectively, covalently attached to the base dU--and incorporated them in the central positions of oligodeoxynucleotides (ODNs) so as to develop new types of quencher-free linear beacon probes and investigate the effect of functionalization of the fluorene scaffold on the photophysical properties of the fluorescent ODNs. The ODNs containing adenine flanking bases (FBs) displayed a selective fluorescence "turn-off" response to mismatched targets with guanine bases; this suggests that these probes could be used as base-discriminating fluorescent nucleotides. On the other hand, we observed a "turn-on" response to matched targets when the UDBF and UDBT units of ODNs containing pyrimidine-based FBs were positioned opposite the four natural nucleobases. In particular, an ODN incorporating UDBT and cytosine FBs has potential use in single-nucleotide polymorphism typing.
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Affiliation(s)
- Jiwon Lee
- Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, 1370 Sankyuk-dong, Buk-gu, Daegu 702-701, South Korea
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33
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Holzhauser C, Wagenknecht HA. DNA and RNA “Traffic Lights”: Synthetic Wavelength-Shifting Fluorescent Probes Based on Nucleic Acid Base Substitutes for Molecular Imaging. J Org Chem 2013; 78:7373-9. [DOI: 10.1021/jo4010102] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Carolin Holzhauser
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe,
Germany
| | - Hans-Achim Wagenknecht
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe,
Germany
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34
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Ditmangklo B, Boonlua C, Suparpprom C, Vilaivan T. Reductive alkylation and sequential reductive alkylation-click chemistry for on-solid-support modification of pyrrolidinyl peptide nucleic acid. Bioconjug Chem 2013; 24:614-25. [PMID: 23517168 DOI: 10.1021/bc3005914] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A methodology for the site-specific attachment of fluorophores to the backbone of pyrrolidinyl peptide nucleic acids (PNAs) with an α/β-backbone derived from D-prolyl-(1S,2S)-2-aminocyclopentanecarboxylic acid (acpcPNA) has been developed. The strategy involves a postsynthetic reductive alkylation of the aldehyde-containing labels onto the acpcPNA that was previously modified with (3R,4S)-3-aminopyrrolidine-4-carboxylic acid on the solid support. The reductive alkylation reaction is remarkably efficient and compatible with a range of reactive functional groups including Fmoc-protected amino, azide, and alkynes. This allows further attachment of readily accessible carboxyl-, alkyne-, or azide-containing labels via amide bond formation or Cu-catalyzed azide-alkyne cycloaddition (CuAAC, also known as click chemistry). The label attached in this way does not negatively affect the affinity and specificity of the pairing of the acpcPNA to its DNA target. Applications of this methodology in creating self-reporting pyrene- and thiazole orange-labeled acpcPNA probes that can yield a change in fluorescence in response to the presence of the correct DNA target have also been explored. A strong fluorescence enhancement was observed with thiazole orange-labeled acpcPNA in the presence of DNA. The specificity could be further improved by enzymatic digestion with S1 nuclease, providing a 9- to 60-fold fluorescence enhancement with fully complementary DNA and a less than 3.5-fold enhancement with mismatched DNA targets.
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Affiliation(s)
- Boonsong Ditmangklo
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand
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35
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Socher E, Knoll A, Seitz O. Dual fluorophore PNA FIT-probes--extremely responsive and bright hybridization probes for the sensitive detection of DNA and RNA. Org Biomol Chem 2013; 10:7363-71. [PMID: 22864341 DOI: 10.1039/c2ob25925g] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Fluorescently labeled oligonucleotides are commonly employed as probes to detect specific DNA or RNA sequences in homogeneous solution. Useful probes should experience strong increases in fluorescent emission upon hybridization with the target. We developed dual labeled peptide nucleic acid probes, which signal the presence of complementary DNA or RNA by up to 450-fold enhancements of fluorescence intensity. This enabled the very sensitive detection of a DNA target (40 pM LOD), which was detectable at less than 0.1% of the beacon concentration. In contrast to existing DNA-based molecular beacons, this PNA-based method does not require a stem sequence to enforce dye-dye communication. Rather, the method relies on the energy transfer between a "smart" thiazole orange (TO) nucleotide, which requires formation of the probe-target complex in order to become fluorescent, and terminally appended acceptor dyes. To improve upon fluorescence responsiveness the energy pathways were dissected. Hydrophobic, spectrally mismatched dye combinations allowed significant (99.97%) decreases of background emission in the absence of a target. By contrast, spectral overlap between TO donor emission and acceptor excitation enabled extremely bright FRET signals. This and the large apparent Stokes shift (82 nm) suggests potential applications in the detection of specific RNA targets in biogenic matrices without the need of sample pre-processing prior to detection.
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Affiliation(s)
- Elke Socher
- Department of Chemistry, Humboldt University Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany
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36
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Hövelmann F, Bethge L, Seitz O. Single labeled DNA FIT probes for avoiding false-positive signaling in the detection of DNA/RNA in qPCR or cell media. Chembiochem 2012; 13:2072-81. [PMID: 22936610 DOI: 10.1002/cbic.201200397] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Indexed: 12/13/2022]
Abstract
Oligonucleotide hybridization probes that fluoresce upon binding to complementary nucleic acid targets allow the real-time detection of DNA or RNA in homogeneous solution. The most commonly used probes rely on the distance-dependent interaction between a fluorophore and another label. Such dual-labeled oligonucleotides signal the change of the global conformation that accompanies duplex formation. However, undesired nonspecific binding events and/or probe degradation also lead to changes in the label-label distance and, thus, to ambiguities in fluorescence signaling. Herein, we introduce singly labeled DNA probes, "DNA FIT probes", that are designed to avoid false-positive signals. A thiazole orange (TO) intercalator dye serves as an artificial base in the DNA probe. The probes show little background because the attachment mode hinders 1) interactions of the "TO base" in cis with the disordered nucleobases of the single strand, and 2) intercalation of the "TO nucleotide" with double strands in trans. However, formation of the probe-target duplex enforces stacking and increases the fluorescence of the TO base. We explored open-chain and carbocyclic nucleotides. We show that the incorporation of the TO nucleotides has no effect on the thermal stability of the probe-target complexes. DNA and RNA targets provided up to 12-fold enhancements of the TO emission upon hybridization of DNA FIT probes. Experiments in cell media demonstrated that false-positive signaling was prevented when DNA FIT probes were used. Of note, DNA FIT probes tolerate a wide range of hybridization temperature; this enabled their application in quantitative polymerase chain reactions.
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Affiliation(s)
- Felix Hövelmann
- Institut für Chemie der Humboldt-Universität zu Berlin, Brook-Taylor Strasse 2, 12489 Berlin, Germany
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37
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Kimura Y, Hanami T, Tanaka Y, de Hoon MJL, Soma T, Harbers M, Lezhava A, Hayashizaki Y, Usui K. Effect of thiazole orange doubly labeled thymidine on DNA duplex formation. Biochemistry 2012; 51:6056-67. [PMID: 22765348 DOI: 10.1021/bi300293d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Nucleic acid oligonucleotides are widely used in hybridization experiments for specific detection of complementary nucleic acid sequences. For design and application of oligonucleotides, an understanding of their thermodynamic properties is essential. Recently, exciton-controlled hybridization-sensitive fluorescent oligonucleotides (ECHOs) were developed as uniquely labeled DNA oligomers containing commonly one thymidine having two covalently linked thiazole orange dye moieties. The fluorescent signal of an ECHO is strictly hybridization-controlled, where the dye moieties have to intercalate into double-stranded DNA for signal generation. Here we analyzed the hybridization thermodynamics of ECHO/DNA duplexes, and thermodynamic parameters were obtained from melting curves of 64 ECHO/DNA duplexes measured by ultraviolet absorbance and fluorescence. Both methods demonstrated a substantial increase in duplex stability (ΔΔG°(37) ~ -2.6 ± 0.7 kcal mol(-1)) compared to that of DNA/DNA duplexes of the same sequence. With the exception of T·G mismatches, this increased stability was mostly unaffected by other mismatches in the position opposite the labeled nucleotide. A nearest neighbor model was constructed for predicting thermodynamic parameters for duplex stability. Evaluation of the nearest neighbor parameters by cross validation tests showed higher predictive reliability for the fluorescence-based than the absorbance-based parameters. Using our experimental data, a tool for predicting the thermodynamics of formation of ECHO/DNA duplexes was developed that is freely available at http://genome.gsc.riken.jp/echo/thermodynamics/. It provides reliable thermodynamic data for using the unique features of ECHOs in fluorescence-based experiments.
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Affiliation(s)
- Yasumasa Kimura
- RIKEN Omics Science Center (OSC), RIKEN Yokohama Institute, 1-7-22 Suehiro-cho, Yokohama, Kanagawa 230-0045, Japan.
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38
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Berndt F, Ioffe I, Granovsky AA, Mahrwald R, Tannert S, Kovalenko SA, Ernsting NP. 7-Amino-dibenzofuran-3-carboxylate: A new probe for femtosecond dynamic microsolvation studies of biomolecules. J Photochem Photobiol A Chem 2012. [DOI: 10.1016/j.jphotochem.2012.02.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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39
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Loakes D. Nucleotides and nucleic acids; oligo- and polynucleotides. ORGANOPHOSPHORUS CHEMISTRY 2012. [DOI: 10.1039/9781849734875-00169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- David Loakes
- Medical Research Council Laboratory of Molecular Biology, Hills Road Cambridge CB2 2QH UK
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40
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Ryu JH, Heo JY, Bang EK, Hwang GT, Kim BH. Quencher-free linear beacon systems containing 2-ethynylfluorenone-labeled 2′-deoxyuridine units. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.10.092] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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41
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Furukawa K, Hattori M, Ohki T, Kitamura Y, Kitade Y, Ueno Y. Nucleic acid probe containing fluorescent tricyclic base-linked acyclonucleoside for detection of single nucleotide polymorphisms. Bioorg Med Chem 2011; 20:16-24. [PMID: 22177406 DOI: 10.1016/j.bmc.2011.11.045] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2011] [Revised: 11/19/2011] [Accepted: 11/21/2011] [Indexed: 11/16/2022]
Abstract
The development of a reliable and simple method for detecting single nucleotide polymorphisms (SNPs), common genetic variations in the human genome, is currently an important research area because SNPs are important for identifying disease-causing genes and for pharmacogenetic studies. Here, we developed a novel method for SNP detection. We designed and synthesized DNA probes containing a fluorescent tricyclic base-linked acyclonucleoside P. The type of nucleobases involved in the SNP sites in the DNA and RNA targets could be determined using four DNA probes containing P. Thus, this system would provide a novel and simple method for detecting SNPs in DNA and RNA targets.
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Affiliation(s)
- Kinji Furukawa
- Department of Biomolecular Science, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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42
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Hattori M, Ohki T, Yanase E, Ueno Y. Fluorescence detection of single nucleotide polymorphisms using nucleic acid probe containing tricyclic base-linked acyclonucleoside. Bioorg Med Chem Lett 2011; 22:253-7. [PMID: 22133629 DOI: 10.1016/j.bmcl.2011.11.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Revised: 10/24/2011] [Accepted: 11/07/2011] [Indexed: 11/20/2022]
Abstract
A reliable and simple method for detecting nucleobase mutations is very important clinically because sequence variations in human DNA cause genetic diseases and genetically influenced traits. A majority of sequence variations are attributed to single nucleotide polymorphisms (SNPs). Here, we developed a method for SNP detection using DNA probes that contained a fluorescent tricyclic base-linked acyclonucleoside N. The type of nucleobases involved in the SNP sites in an RNA target could be determined using four DNA probes containing N. Further, we found that the SNP in the RNA target could be detected by a visible color. Thus, this system would provide a novel and simple method for detecting SNPs in an RNA target.
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Affiliation(s)
- Mayumi Hattori
- Department of Biomolecular Science, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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Stadler AL, Delos Santos JO, Stensrud ES, Dembska A, Silva GL, Liu S, Shank NI, Kunttas-Tatli E, Sobers CJ, Gramlich PME, Carell T, Peteanu LA, McCartney BM, Armitage BA. Fluorescent DNA nanotags featuring covalently attached intercalating dyes: synthesis, antibody conjugation, and intracellular imaging. Bioconjug Chem 2011; 22:1491-502. [PMID: 21755981 DOI: 10.1021/bc100485f] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We have synthesized fluorescent DNA duplexes featuring multiple thiazole orange (TO) intercalating dyes covalently attached to the DNA via a triazole linkage. The intercalating dyes stabilize the duplex against thermal denaturation and show bright fluorescence in the green region of the spectrum. The emission color can be changed to orange or red by addition of energy-accepting Cy3 or Cy5 dyes attached covalently to the DNA duplex. The dye-modified DNA duplexes were then attached to a secondary antibody for intracellular fluorescence imaging of centrosomes in Drosophila embryos. Bright fluorescent foci were observed at the centrosomes in both the donor (TO) and acceptor (Cy5) channels, because the energy transfer efficiency is moderate. Monitoring the Cy5 emission channel significantly minimized the background signal because of the large shift in emission wavelength allowed by energy transfer.
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Affiliation(s)
- Andrea L Stadler
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
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Biner SM, Kummer D, Malinovskii VL, Häner R. Signal control by self-assembly of fluorophores in a molecular beacon—a model study. Org Biomol Chem 2011; 9:2628-33. [DOI: 10.1039/c0ob01132k] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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