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Heel SV, Breuker K. Investigating the Intramolecular Competition of Different RNA Binding Motifs for Neomycin B by Native Top-Down Mass Spectrometry. Chempluschem 2024; 89:e202400178. [PMID: 38758051 DOI: 10.1002/cplu.202400178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 04/13/2024] [Indexed: 05/18/2024]
Abstract
The ongoing search for small molecule drugs that target ribonucleic acids (RNA) is complicated by a limited understanding of the principles that govern RNA-small molecule interactions. Here we have used stoichiometry-resolved native top-down mass spectrometry (MS) to study the binding of neomycin B to small model hairpin RNAs, an unstructured RNA, and a viral RNA construct. For 15-22 nt model RNAs with hairpin structure, we found that neomycin B binding to hairpin loops relies on interactions with both the nucleobases and the 2'-OH groups, and that a simple 5' or 3' overhang can introduce an additional binding motif. For a 47 nt RNA construct derived from stem IA of the human immunodeficiency virus 1 (HIV-1) rev response element (RRE) RNA, native top-down MS identified four different binding motifs, of which the purine-rich internal loop showed the highest affinity for neomycin B. Stoichiometry-resolved binding site mapping by native top-down MS allows for a new perspective on binding specificity, and has the potential to reveal unexpected principles of small molecule binding to RNA.
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Affiliation(s)
- Sarah Viola Heel
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020, Innsbruck, Austria
| | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020, Innsbruck, Austria
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2
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Herbert C, Valesyan S, Kist J, Limbach PA. Analysis of RNA and Its Modifications. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2024; 17:47-68. [PMID: 38594935 DOI: 10.1146/annurev-anchem-061622-125954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Ribonucleic acids (RNAs) are key biomolecules responsible for the transmission of genetic information, the synthesis of proteins, and modulation of many biochemical processes. They are also often the key components of viruses. Synthetic RNAs or oligoribonucleotides are becoming more widely used as therapeutics. In many cases, RNAs will be chemically modified, either naturally via enzymatic systems within a cell or intentionally during their synthesis. Analytical methods to detect, sequence, identify, and quantify RNA and its modifications have demands that far exceed requirements found in the DNA realm. Two complementary platforms have demonstrated their value and utility for the characterization of RNA and its modifications: mass spectrometry and next-generation sequencing. This review highlights recent advances in both platforms, examines their relative strengths and weaknesses, and explores some alternative approaches that lie at the horizon.
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Affiliation(s)
- Cassandra Herbert
- Rieveschl Laboratories for Mass Spectrometry, Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, USA;
| | - Satenik Valesyan
- Rieveschl Laboratories for Mass Spectrometry, Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, USA;
| | - Jennifer Kist
- Rieveschl Laboratories for Mass Spectrometry, Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, USA;
| | - Patrick A Limbach
- Rieveschl Laboratories for Mass Spectrometry, Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, USA;
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3
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Heel SV, Juen F, Bartosik K, Micura R, Kreutz C, Breuker K. Resolving the intricate binding of neomycin B to multiple binding motifs of a neomycin-sensing riboswitch aptamer by native top-down mass spectrometry and NMR spectroscopy. Nucleic Acids Res 2024; 52:4691-4701. [PMID: 38567725 PMCID: PMC11077050 DOI: 10.1093/nar/gkae224] [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: 08/07/2023] [Revised: 03/05/2024] [Accepted: 03/25/2024] [Indexed: 05/09/2024] Open
Abstract
Understanding small molecule binding to RNA can be complicated by an intricate interplay between binding stoichiometry, multiple binding motifs, different occupancies of different binding motifs, and changes in the structure of the RNA under study. Here, we use native top-down mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy to experimentally resolve these factors and gain a better understanding of the interactions between neomycin B and the 40 nt aptamer domain of a neomycin-sensing riboswitch engineered in yeast. Data from collisionally activated dissociation of the 1:1, 1:2 and 1:3 RNA-neomycin B complexes identified a third binding motif C of the riboswitch in addition to the two motifs A and B found in our previous study, and provided occupancies of the different binding motifs for each complex stoichiometry. Binding of a fourth neomycin B molecule was unspecific according to both MS and NMR data. Intriguingly, all major changes in the aptamer structure can be induced by the binding of the first neomycin B molecule regardless of whether it binds to motif A or B as evidenced by stoichiometry-resolved MS data together with titration data from 1H NMR spectroscopy in the imino proton region. Specific binding of the second and third neomycin B molecules further stabilizes the riboswitch aptamer, thereby allowing for a gradual response to increasing concentrations of neomycin B, which likely leads to a fine-tuning of the cellular regulatory mechanism.
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Affiliation(s)
- Sarah Viola Heel
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Fabian Juen
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Karolina Bartosik
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Ronald Micura
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
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4
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Hannauer F, Black R, Ray AD, Stulz E, Langley GJ, Holman SW. Review of fragmentation of synthetic single-stranded oligonucleotides by tandem mass spectrometry from 2014 to 2022. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2023; 37:e9596. [PMID: 37580500 PMCID: PMC10909466 DOI: 10.1002/rcm.9596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 08/16/2023]
Abstract
The fragmentation of oligonucleotides by mass spectrometry allows for the determination of their sequences. It is necessary to understand how oligonucleotides dissociate in the gas phase, which allows interpretation of data to obtain sequence information. Since 2014, a range of fragmentation mechanisms, including a novel internal rearrangement, have been proposed using different ion dissociation techniques. The recent publications have focused on the fragmentation of modified oligonucleotides such as locked nucleic acids, modified nucleobases (methylated, spacer, nebularine and aminopurine) and modification to the carbon 2'-position on the sugar ring; these modified oligonucleotides are of great interest as therapeutics. Comparisons of different dissociation techniques have been reported, including novel approaches such as plasma electron detachment dissociation and radical transfer dissociation. This review covers the period 2014-2022 and details the new knowledge gained with respect to oligonucleotide dissociation using tandem mass spectrometry (without priori sample digestion) during that time, with a specific focus on synthetic single-stranded oligonucleotides.
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Affiliation(s)
- Fabien Hannauer
- Chemistry, Faculty of Engineering and Physical SciencesUniversity of SouthamptonSouthamptonUK
| | - Rachelle Black
- New Modalities & Parenteral Development, Pharmaceutical Technology & Development, OperationsAstraZenecaMacclesfieldUK
| | - Andrew D. Ray
- New Modalities & Parenteral Development, Pharmaceutical Technology & Development, OperationsAstraZenecaMacclesfieldUK
| | - Eugen Stulz
- Chemistry, Faculty of Engineering and Physical SciencesUniversity of SouthamptonSouthamptonUK
| | - G. John Langley
- Chemistry, Faculty of Engineering and Physical SciencesUniversity of SouthamptonSouthamptonUK
| | - Stephen W. Holman
- Chemical Development, Pharmaceutical Technology & Development, OperationsAstraZenecaMacclesfieldUK
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Heel SV, Bartosik K, Juen F, Kreutz C, Micura R, Breuker K. Native Top-Down Mass Spectrometry Uncovers Two Distinct Binding Motifs of a Functional Neomycin-Sensing Riboswitch Aptamer. J Am Chem Soc 2023. [PMID: 37420313 PMCID: PMC10360057 DOI: 10.1021/jacs.3c02774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/09/2023]
Abstract
Understanding how ligands bind to ribonucleic acids (RNA) is important for understanding RNA recognition in biological processes and drug development. Here, we have studied neomycin B binding to neomycin-sensing riboswitch aptamer constructs by native top-down mass spectrometry (MS) using electrospray ionization (ESI) and collisionally activated dissociation (CAD). Our MS data for a 27 nt aptamer construct reveal the binding site and ligand interactions, in excellent agreement with the structure derived from nuclear magnetic resonance (NMR) studies. Strikingly, for an extended 40 nt aptamer construct, which represents the sequence with the highest regulatory factor for riboswitch function, we identified two binding motifs for neomycin B binding, one corresponding to the bulge-loop motif of the 27 nt construct and the other one in the minor groove of the lower stem, which according to the MS data are equally populated. By replacing a noncanonical with a canonical base pair in the lower stem of the 40 nt aptamer, we can reduce binding to the minor groove motif from ∼50 to ∼30%. Conversely, the introduction of a CUG/CUG motif in the lower stem shifts the binding equilibrium in favor of minor groove binding. The MS data reveal site-specific and stoichiometry-resolved information on aminoglycoside binding to RNA that is not directly accessible by other methods and underscore the role of noncanonical base pairs in RNA recognition by aminoglycosides.
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Affiliation(s)
- Sarah Viola Heel
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Karolina Bartosik
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Fabian Juen
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Ronald Micura
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
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Zhang HX, Qin JF, Sun JF, Pan Y, Yan TM, Wang CY, Bai LP, Zhu GY, Jiang ZH, Zhang W. Selective Chemical Labeling Strategy for Oligonucleotides Determination: A First Application to Full-Range Profiling of Transfer RNA Modifications. Anal Chem 2023; 95:686-694. [PMID: 36601728 DOI: 10.1021/acs.analchem.2c02302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
To date, the extremely high polarity and poor signal intensity of macromolecular nucleic acids are greatly impeding the progress of mass spectrometry technology in the quality control of nucleic acid drugs and the characterization of DNA oxidation and RNA modifications. We recently described a general N-(tert-butyldimethylsilyl)-N-methyl-trifluoroacetamide (MTBSTFA) labeling method for oligonucleotide determination and applied it to the full-range profiling of tRNA in vitro and in vivo studies for the first time. The primary advantages of this method include strong retention, no observable byproducts, predictable and easily interpreted MS2 data, and the circumvention of instrument harmful reagents that were necessary in previous methods. Selective labeling of N-(tert-butyldimethylsilyl)-N-methyl-trifluoroacetamide to the terminal phosphate groups of oligonucleotides endows it broadly applicable for DNA/RNA profiling. Moreover, the improvement of sequence coverage was achieved in yeast tRNAphe(GAA) analysis owing to this method's good detection capability of 1-12 nucleotides in length. We also extended this strategy to determine the abundance of modified bases and discover new modifications via digesting RNA into single-nucleotide products, promoting the comprehensive mapping of RNA. The easy availability of derivatization reagent and the simple, rapid one-step reaction render it easy to operate for researchers. When applied in characterizing tRNAs in HepG2 cells and rats with nonalcoholic fatty liver disease, a fragment of U[m1G][m2G], specific for tRNAAsn(QUU) in cells, was significantly upregulated, indicating a possible clue to nonalcoholic fatty liver disease pathogenesis.
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Affiliation(s)
- Hui-Xia Zhang
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Jian-Feng Qin
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Jian-Feng Sun
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Yu Pan
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Tong-Meng Yan
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Cai-Yun Wang
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Li-Ping Bai
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Guo-Yuan Zhu
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Zhi-Hong Jiang
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
| | - Wei Zhang
- State Key Laboratory of Quality Research in Chinese Medicines, Guangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious Disease, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau 999078, People's Republic of China
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7
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Palasser M, Breuker K. RNA Chemical Labeling with Site-Specific, Relative Quantification by Mass Spectrometry for the Structural Study of a Neomycin-Sensing Riboswitch Aptamer Domain. Chempluschem 2022; 87:e202200256. [PMID: 36220343 PMCID: PMC9828840 DOI: 10.1002/cplu.202200256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/14/2022] [Indexed: 01/12/2023]
Abstract
High-resolution mass spectrometry was used for the label-free, direct localization and relative quantification of CMC+ -modifications of a neomycin-sensing riboswitch aptamer domain in the absence and presence of the aminoglycoside ligands neomycin B, ribostamycin, and paromomycin. The chemical probing and MS data for the free riboswitch show high exposure to solvent of the uridine nucleobases U7, U8, U13, U14, U18 as part of the proposed internal and apical loops, but those of U10 and U21 as part of the proposed internal loop were found to be far less exposed than expected. Thus, our data are in better agreement with the proposed secondary structure of the riboswitch in complexes with aminoglycosides than with that of free RNA. For the riboswitch in complexes with neomycin B, ribostamycin, and paromomycin, we found highly similar CMC+ -modification patterns and excellent agreement with previous NMR studies. Differences between the chemical probing and MS data in the absence and presence of the aminoglycoside ligands were quantitative rather than qualitative (i. e., the same nucleobases were labeled, but to different extents) and can be rationalized by stabilization of both the proposed bulge and the apical loop by aminoglycoside binding. Our study shows that chemical probing and mass spectrometry can provide important structural information and complement other techniques such as NMR spectroscopy.
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Affiliation(s)
- Michael Palasser
- Institut of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
| | - Kathrin Breuker
- Institut of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
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8
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Greis K, Kirschbaum C, Taccone MI, Götze M, Gewinner S, Schöllkopf W, Meijer G, von Helden G, Pagel K. Studying the Key Intermediate of RNA Autohydrolysis by Cryogenic Gas-Phase Infrared Spectroscopy. Angew Chem Int Ed Engl 2022; 61:e202115481. [PMID: 35231141 PMCID: PMC9314874 DOI: 10.1002/anie.202115481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Indexed: 11/09/2022]
Abstract
Over the course of the COVID-19 pandemic, mRNA-based vaccines have gained tremendous importance. The development and analysis of modified RNA molecules benefit from advanced mass spectrometry and require sufficient understanding of fragmentation processes. Analogous to the degradation of RNA in solution by autohydrolysis, backbone cleavage of RNA strands was equally observed in the gas phase; however, the fragmentation mechanism remained elusive. In this work, autohydrolysis-like intermediates were generated from isolated RNA dinucleotides in the gas phase and investigated using cryogenic infrared spectroscopy in helium nanodroplets. Data from both experiment and density functional theory provide evidence for the formation of a five-membered cyclic phosphate intermediate and rule out linear or six-membered structures. Furthermore, the experiments show that another prominent condensed-phase reaction of RNA nucleotides can be induced in the gas phase: the tautomerization of cytosine. Both observed reactions are therefore highly universal and intrinsic properties of the investigated molecules.
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Affiliation(s)
- Kim Greis
- Institut für Chemie und BiochemieFreie Universität BerlinArnimallee 2214195BerlinGermany
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Carla Kirschbaum
- Institut für Chemie und BiochemieFreie Universität BerlinArnimallee 2214195BerlinGermany
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Martín I. Taccone
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Michael Götze
- Institut für Chemie und BiochemieFreie Universität BerlinArnimallee 2214195BerlinGermany
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Sandy Gewinner
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Wieland Schöllkopf
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Gerard Meijer
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Gert von Helden
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Kevin Pagel
- Institut für Chemie und BiochemieFreie Universität BerlinArnimallee 2214195BerlinGermany
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
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9
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Greis K, Kirschbaum C, Taccone MI, Götze M, Gewinner S, Schöllkopf W, Meijer G, Helden G, Pagel K. Untersuchung des reaktiven Intermediats der RNA Autohydrolyse mittels kryogener Infrarotspektroskopie in der Gasphase. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202115481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kim Greis
- Institut für Chemie und Biochemie Freie Universität Berlin Arnimallee 22 14195 Berlin Deutschland
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Carla Kirschbaum
- Institut für Chemie und Biochemie Freie Universität Berlin Arnimallee 22 14195 Berlin Deutschland
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Martín I. Taccone
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Michael Götze
- Institut für Chemie und Biochemie Freie Universität Berlin Arnimallee 22 14195 Berlin Deutschland
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Sandy Gewinner
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Wieland Schöllkopf
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Gerard Meijer
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Gert Helden
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
| | - Kevin Pagel
- Institut für Chemie und Biochemie Freie Universität Berlin Arnimallee 22 14195 Berlin Deutschland
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Deutschland
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10
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Santos IC, Lanzillotti M, Shilov I, Basanta-Sanchez M, Roushan A, Lawler R, Tang W, Bern M, Brodbelt JS. Ultraviolet Photodissociation and Activated Electron Photodetachment Mass Spectrometry for Top-Down Sequencing of Modified Oligoribonucleotides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:510-520. [PMID: 35157441 DOI: 10.1021/jasms.1c00340] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
With the increased development of new RNA-based therapeutics, the need for robust analytical methods for confirming sequences and mapping modifications has accelerated. Characterizing modified ribonucleic acids using mass spectrometry is challenging because diagnostic fragmentation may be suppressed for modified nucleotides, thus hampering complete sequence coverage and the confident localization of modifications. Ultraviolet photodissociation (UVPD) has shown great potential for the characterization of nucleic acids due to extensive backbone fragmentation. Activated electron photodetachment dissociation (a-EPD) has also been used as an alternative to capitalize on the dominant charge-reduction pathway prevalent in UVPD, facilitate dissociation, and produce high abundances of fragment ions. Here, we compare higher-energy collisional activation (HCD), UVPD using 193 and 213 nm photons, and a-EPD for the top-down sequencing of modified nucleic acids, including methylated, phosphorothioate, and locked nucleic acid-modified DNA. The presence of these modifications alters the fragmentation pathways observed upon UVPD and a-EPD, and extensive backbone cleavage is observed that results in the production of fragment ions that retain the modifications and allow them to be pinpointed. LNA and 2'-O-methoxy phosphorothioate modifications caused a significant suppression of fragmentation for UVPD but not for a-EPD, whereas phosphorothioate bonds did not cause any significant suppression for either method. The incorporation of 2'-O-methyl modifications suppressed fragmentation of the antisense strand of patisiran, which resulted in some gaps in sequence coverage. However, UVPD provided the highest sequence coverage when compared to a-EPD.
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Affiliation(s)
- Inês C Santos
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Michael Lanzillotti
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Ignat Shilov
- Protein Metrics Inc., 20863 Stevens Creek Boulevard, Cupertino, California 95014, United States
| | - Maria Basanta-Sanchez
- Protein Metrics Inc., 20863 Stevens Creek Boulevard, Cupertino, California 95014, United States
| | - Abhishek Roushan
- Protein Metrics Inc., 20863 Stevens Creek Boulevard, Cupertino, California 95014, United States
| | - Rose Lawler
- Protein Metrics Inc., 20863 Stevens Creek Boulevard, Cupertino, California 95014, United States
| | - Wilfred Tang
- Protein Metrics Inc., 20863 Stevens Creek Boulevard, Cupertino, California 95014, United States
| | - Marshall Bern
- Protein Metrics Inc., 20863 Stevens Creek Boulevard, Cupertino, California 95014, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
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11
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Santos IC, Brodbelt JS. Recent developments in the characterization of nucleic acids by liquid chromatography, capillary electrophoresis, ion mobility, and mass spectrometry (2010-2020). J Sep Sci 2021; 44:340-372. [PMID: 32974962 PMCID: PMC8378248 DOI: 10.1002/jssc.202000833] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/18/2020] [Accepted: 09/21/2020] [Indexed: 12/25/2022]
Abstract
The development of new strategies for the analysis of nucleic acids has gained momentum due to the increased interest in using these biomolecules as drugs or drug targets. The application of new mass spectrometry ion activation techniques and the optimization of separation methods including liquid chromatography, capillary electrophoresis, and ion mobility have allowed more detailed characterization of nucleic acids and oligonucleotide therapeutics including confirmation of sequence, localization of modifications and interaction sites, and structural analysis as well as identification of failed sequences and degradation products. This review will cover tandem mass spectrometry methods as well as the recent developments in liquid chromatography, capillary electrophoresis, and ion mobility coupled to mass spectrometry for the analysis of nucleic acids and oligonucleotides.
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Affiliation(s)
- Inês C Santos
- Department of Chemistry, University of Texas at Austin, Austin, Texas, USA
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12
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Native mass spectrometry reveals the initial binding events of HIV-1 rev to RRE stem II RNA. Nat Commun 2020; 11:5750. [PMID: 33188169 PMCID: PMC7666190 DOI: 10.1038/s41467-020-19144-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 09/29/2020] [Indexed: 11/24/2022] Open
Abstract
Nuclear export complexes composed of rev response element (RRE) ribonucleic acid (RNA) and multiple molecules of rev protein are promising targets for the development of therapeutic strategies against human immunodeficiency virus type 1 (HIV-1), but their assembly remains poorly understood. Using native mass spectrometry, we show here that rev initially binds to the upper stem of RRE IIB, from where it is relayed to binding sites that allow for rev dimerization. The newly discovered binding region implies initial rev recognition by nucleotides that are not part of the internal loop of RRE stem IIB RNA, which was previously identified as the preferred binding region. Our study highlights the unique capability of native mass spectrometry to separately study the binding interfaces of RNA/protein complexes of different stoichiometry, and provides a detailed understanding of the mechanism of RRE/rev association with implications for the rational design of potential drugs against HIV-1 infection. The HIV-1 RNA-binding protein rev facilitates nuclear export of viral RNA. Here, the authors use native mass spectrometry to study the interactions between rev-derived peptides and rev response elements of HIV-1 RNA, providing mechanistic insights into rev recognition and recruitment.
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13
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Hagelskamp F, Borland K, Ramos J, Hendrick AG, Fu D, Kellner S. Broadly applicable oligonucleotide mass spectrometry for the analysis of RNA writers and erasers in vitro. Nucleic Acids Res 2020; 48:e41. [PMID: 32083657 PMCID: PMC7144906 DOI: 10.1093/nar/gkaa091] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 01/23/2020] [Accepted: 02/06/2020] [Indexed: 12/20/2022] Open
Abstract
RNAs are post-transcriptionally modified by dedicated writer or eraser enzymes that add or remove specific modifications, respectively. Mass spectrometry (MS) of RNA is a useful tool to study the modification state of an oligonucleotide (ON) in a sensitive manner. Here, we developed an ion-pairing reagent free chromatography for positive ion detection of ONs by low- and high-resolution MS, which does not interfere with other types of small compound analyses done on the same instrument. We apply ON-MS to determine the ONs from an RNase T1 digest of in vitro transcribed tRNA, which are purified after ribozyme-fusion transcription by automated size exclusion chromatography. The thus produced tRNAValAAC is substrate of the human tRNA ADAT2/3 enzyme and we confirm the deamination of adenosine to inosine and the formation of tRNAValIACin vitro by ON-MS. Furthermore, low resolution ON-MS is used to monitor the demethylation of ONs containing 1-methyladenosine by bacterial AlkB in vitro. The power of high-resolution ON-MS is demonstrated by the detection and mapping of modified ONs from native total tRNA digested with RNase T1. Overall, we present an oligonucleotide MS method which is broadly applicable to monitor in vitro RNA (de-)modification processes and native RNA.
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Affiliation(s)
- Felix Hagelskamp
- Department of Chemistry, Ludwig Maximilians University Munich, Butenandtstrasse 5-13, 81377 Munich, Germany
| | - Kayla Borland
- Department of Chemistry, Ludwig Maximilians University Munich, Butenandtstrasse 5-13, 81377 Munich, Germany
| | - Jillian Ramos
- Department of Biology, Center for RNA Biology, University of Rochester, Rochester, NY 14627, USA
| | - Alan G Hendrick
- STORM Therapeutics, Moneta Building, Babraham Research Campus, Cambridge CB22 3AT UK
| | - Dragony Fu
- Department of Biology, Center for RNA Biology, University of Rochester, Rochester, NY 14627, USA
| | - Stefanie Kellner
- Department of Chemistry, Ludwig Maximilians University Munich, Butenandtstrasse 5-13, 81377 Munich, Germany
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14
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Calderisi G, Glasner H, Breuker K. Radical Transfer Dissociation for De Novo Characterization of Modified Ribonucleic Acids by Mass Spectrometry. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Giovanni Calderisi
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität Innsbruck Innrain 80/82 6020 Innsbruck Austria
| | - Heidelinde Glasner
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität Innsbruck Innrain 80/82 6020 Innsbruck Austria
| | - Kathrin Breuker
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität Innsbruck Innrain 80/82 6020 Innsbruck Austria
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15
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Calderisi G, Glasner H, Breuker K. Radical Transfer Dissociation for De Novo Characterization of Modified Ribonucleic Acids by Mass Spectrometry. Angew Chem Int Ed Engl 2020; 59:4309-4313. [PMID: 31867820 PMCID: PMC7065001 DOI: 10.1002/anie.201914275] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Indexed: 12/20/2022]
Abstract
Mass spectrometry (MS) can reliably detect and localize all mass-altering modifications of ribonucleic acids (RNA), but current MS approaches that allow for simultaneous de novo sequencing and modification analysis generally require specialized instrumentation. Here we report a novel RNA dissociation technique, radical transfer dissociation (RTD), that can be used for the comprehensive de novo characterization of ribonucleic acids and their posttranscriptional or synthetic modifications. We demonstrate full sequence coverage for RNA consisting of up to 39 nucleotides and show that RTD is especially useful for RNA with highly labile modifications such as 5-hydroxymethylcytidine and 5-formylcytidine.
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Affiliation(s)
- Giovanni Calderisi
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80/826020InnsbruckAustria
| | - Heidelinde Glasner
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80/826020InnsbruckAustria
| | - Kathrin Breuker
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80/826020InnsbruckAustria
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16
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Fuchs E, Falschlunger C, Micura R, Breuker K. The effect of adenine protonation on RNA phosphodiester backbone bond cleavage elucidated by deaza-nucleobase modifications and mass spectrometry. Nucleic Acids Res 2019; 47:7223-7234. [PMID: 31276590 PMCID: PMC6698743 DOI: 10.1093/nar/gkz574] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/15/2019] [Accepted: 06/21/2019] [Indexed: 12/14/2022] Open
Abstract
The catalytic strategies of small self-cleaving ribozymes often involve interactions between nucleobases and the ribonucleic acid (RNA) backbone. Here we show that multiply protonated, gaseous RNA has an intrinsic preference for the formation of ionic hydrogen bonds between adenine protonated at N3 and the phosphodiester backbone moiety on its 5'-side that facilitates preferential phosphodiester backbone bond cleavage upon vibrational excitation by low-energy collisionally activated dissociation. Removal of the basic N3 site by deaza-modification of adenine was found to abrogate preferential phosphodiester backbone bond cleavage. No such effects were observed for N1 or N7 of adenine. Importantly, we found that the pH of the solution used for generation of the multiply protonated, gaseous RNA ions by electrospray ionization affects phosphodiester backbone bond cleavage next to adenine, which implies that the protonation patterns in solution are at least in part preserved during and after transfer into the gas phase. Our study suggests that interactions between protonated adenine and phosphodiester moieties of RNA may play a more important mechanistic role in biological processes than considered until now.
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Affiliation(s)
- Elisabeth Fuchs
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Christoph Falschlunger
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Ronald Micura
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
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17
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Vušurović J, Breuker K. Relative Strength of Noncovalent Interactions and Covalent Backbone Bonds in Gaseous RNA-Peptide Complexes. Anal Chem 2019; 91:1659-1664. [PMID: 30614682 PMCID: PMC6335609 DOI: 10.1021/acs.analchem.8b05387] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Interactions of ribonucleic acids (RNA) with basic ligands such as proteins or aminoglycosides play a key role in fundamental biological processes. Native top-down mass spectrometry (MS) has recently been extended to binding site mapping of RNA-ligand interactions by collisionally activated dissociation, without the need for laborious sample preparation procedures. The technique relies on the preservation of noncovalent interactions at energies that are sufficiently high to cause RNA backbone cleavage. In this study, we address the question of how many and what types of noncovalent interactions allow for binding site mapping by top-down MS. We show that proton transfer from protonated ligand to deprotonated RNA within salt bridges initiates loss of the ligand, but that proton transfer becomes energetically unfavorable in the presence of additional hydrogen bonds such that the noncovalent interactions remain stronger than the covalent RNA backbone bonds.
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Affiliation(s)
- Jovana Vušurović
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI) , Universität Innsbruck , Innrain 80-82 , 6020 Innsbruck , Austria
| | - Kathrin Breuker
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI) , Universität Innsbruck , Innrain 80-82 , 6020 Innsbruck , Austria
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18
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Titanocene binding to oligonucleotides. J Inorg Biochem 2018; 184:1-7. [PMID: 29635096 DOI: 10.1016/j.jinorgbio.2018.03.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/26/2018] [Accepted: 03/22/2018] [Indexed: 11/23/2022]
Abstract
The binding of titanocene to DNA and RNA was examined by means of electrospray mass spectrometry. Titanocene served as a model for its therapeutically active derivatives. The binding preferences were probed by competition experiments with oligonucleotides of varying nucleobase compositions and sequences. Results from competition experiments revealed a generally increased preference for the binding to phosphate groups adjacent to thymidines, which is affected by the nucleobase sequence of T-rich oligonucleotides. More detailed information about the binding sites was obtained from tandem mass spectrometric experiments. The binding of the transition metal coordination center significantly altered the fragment ion patterns of the oligonucleotides. RNA was found to be less prone to adduct formation, due to intramolecular interactions. The findings from experiments on DNA and RNA were complemented by the examination of backbone- and ribose-modified oligonucleotides.
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19
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Vušurović J, Schneeberger E, Breuker K. Interactions of Protonated Guanidine and Guanidine Derivatives with Multiply Deprotonated RNA Probed by Electrospray Ionization and Collisionally Activated Dissociation. ChemistryOpen 2017; 6:739-750. [PMID: 29226062 PMCID: PMC5715244 DOI: 10.1002/open.201700143] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/06/2017] [Indexed: 11/25/2022] Open
Abstract
Interactions of ribonucleic acid (RNA) with guanidine and guanidine derivatives are important features in RNA-protein and RNA-drug binding. Here we have investigated noncovalently bound complexes of an 8-nucleotide RNA and six different ligands, all of which have a guanidinium moiety, by using electrospray ionization (ESI) and collisionally activated dissociation (CAD) mass spectrometry (MS). The order of complex stability correlated almost linearly with the number of ligand atoms that can potentially be involved in hydrogen-bond or salt-bridge interactions with the RNA, but not with the proton affinity of the ligands. However, ligand dissociation of the complex ions in CAD was generally accompanied by proton transfer from ligand to RNA, which indicated conversion of salt-bridge into hydrogen-bond interactions. The relative stabilities and dissociation pathways of [RNA+m L-n H] n- complexes with different stoichiometries (m=1-5) and net charge (n= 2-5) revealed both specific and unspecific ligand binding to the RNA.
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Affiliation(s)
- Jovana Vušurović
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80–826020InnsbruckAustria
| | - Eva‐Maria Schneeberger
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80–826020InnsbruckAustria
| | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80–826020InnsbruckAustria
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20
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Hari Y, Leumann CJ, Schürch S. What Hinders Electron Transfer Dissociation (ETD) of DNA Cations? JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:2677-2685. [PMID: 28932996 DOI: 10.1007/s13361-017-1791-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/18/2017] [Accepted: 08/18/2017] [Indexed: 06/07/2023]
Abstract
Radical activation methods, such as electron transfer dissociation (ETD), produce structural information complementary to collision-induced dissociation. Herein, electron transfer dissociation of 3-fold protonated DNA hexamers was studied to gain insight into the fragmentation mechanism. The fragmentation patterns of a large set of DNA hexamers confirm cytosine as the primary target of electron transfer. The reported data reveal backbone cleavage by internal electron transfer from the nucleobase to the phosphate linker leading either to a•/w or d/z• ion pairs. This reaction pathway contrasts with previous findings on the dissociation processes after electron capture by DNA cations, suggesting multiple, parallel dissociation channels. However, all these channels merely result in partial fragmentation of the precursor ion because the charge-reduced DNA radical cations are quite stable. Two hypotheses are put forward to explain the low dissociation yield of DNA radical cations: it is either attributed to non-covalent interactions between complementary fragments or to the stabilization of the unpaired electron in stacked nucleobases. MS3 experiments suggest that the charge-reduced species is the intact oligonucleotide. Moreover, introducing abasic sites significantly increases the dissociation yield of DNA cations. Consequently, the stabilization of the unpaired electron by π-π-stacking provides an appropriate rationale for the high intensity of DNA radical cations after electron transfer. Graphical Abstract.
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Affiliation(s)
- Yvonne Hari
- Department of Chemistry and Biochemistry, Freiestrasse 3, 3012, Bern, Switzerland
| | - Christian J Leumann
- Department of Chemistry and Biochemistry, Freiestrasse 3, 3012, Bern, Switzerland
| | - Stefan Schürch
- Department of Chemistry and Biochemistry, Freiestrasse 3, 3012, Bern, Switzerland.
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21
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Glasner H, Riml C, Micura R, Breuker K. Label-free, direct localization and relative quantitation of the RNA nucleobase methylations m6A, m5C, m3U, and m5U by top-down mass spectrometry. Nucleic Acids Res 2017; 45:8014-8025. [PMID: 28549193 PMCID: PMC5570050 DOI: 10.1093/nar/gkx470] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 05/23/2017] [Indexed: 01/28/2023] Open
Abstract
Nucleobase methylations are ubiquitous posttranscriptional modifications of ribonucleic acids (RNA) that can substantially increase the structural diversity of RNA in a highly dynamic fashion with implications for gene expression and human disease. However, high throughput, deep sequencing does not generally provide information on posttranscriptional modifications (PTMs). A promising alternative approach for the characterization of PTMs, i.e. their identification, localization, and relative quantitation, is top-down mass spectrometry (MS). In this study, we have investigated how specific nucleobase methylations affect RNA ionization in electrospray ionization (ESI), and backbone cleavage in collisionally activated dissociation (CAD) and electron detachment dissociation (EDD). For this purpose, we have developed two new approaches for the characterization of RNA methylations in mixtures of either isomers of RNA or nonisomeric RNA forms. Fragment ions from dissociation experiments were analyzed to identify the modification type, to localize the modification sites, and to reveal the site-specific, relative extent of modification for each site.
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Affiliation(s)
- Heidelinde Glasner
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Christian Riml
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Ronald Micura
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
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22
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Schneeberger E, Breuker K. Native Top-Down Mass Spectrometry of TAR RNA in Complexes with a Wild-Type tat Peptide for Binding Site Mapping. Angew Chem Int Ed Engl 2017; 56:1254-1258. [PMID: 28000363 PMCID: PMC5299493 DOI: 10.1002/anie.201610836] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Indexed: 12/18/2022]
Abstract
Ribonucleic acids (RNA) frequently associate with proteins in many biological processes to form more or less stable complex structures. The characterization of RNA-protein complex structures and binding interfaces by nuclear magnetic resonance (NMR) spectroscopy, X-ray crystallography, or strategies based on chemical crosslinking, however, can be quite challenging. Herein, we have explored the use of an alternative method, native top-down mass spectrometry (MS), for probing of complex stoichiometry and protein binding sites at the single-residue level of RNA. Our data show that the electrostatic interactions between HIV-1 TAR RNA and a peptide comprising the arginine-rich binding region of tat protein are sufficiently strong in the gas phase to survive phosphodiester backbone cleavage of RNA by collisionally activated dissociation (CAD), thus allowing its use for probing tat binding sites in TAR RNA by top-down MS. Moreover, the MS data reveal time-dependent 1:2 and 1:1 stoichiometries of the TAR-tat complexes and suggest structural rearrangements of TAR RNA induced by binding of tat peptide.
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Affiliation(s)
- Eva‐Maria Schneeberger
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80-826020InnsbruckAustria
| | - Kathrin Breuker
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80-826020InnsbruckAustria
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23
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Schneeberger E, Breuker K. Native Top‐Down Mass Spectrometry of TAR RNA in Complexes with a Wild‐Type tat Peptide for Binding Site Mapping. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201610836] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Eva‐Maria Schneeberger
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI) Universität Innsbruck Innrain 80-82 6020 Innsbruck Austria
| | - Kathrin Breuker
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI) Universität Innsbruck Innrain 80-82 6020 Innsbruck Austria
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24
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Gebetsberger J, Micura R. Unwinding the twister ribozyme: from structure to mechanism. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 8. [PMID: 27863022 PMCID: PMC5408937 DOI: 10.1002/wrna.1402] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 09/12/2016] [Accepted: 10/10/2016] [Indexed: 11/12/2022]
Abstract
The twister ribozyme motif has been identified by bioinformatic means very recently. Currently, four crystal structures with ordered active sites together with a series of chemical and biochemical data provide insights into how this RNA accomplishes its efficient self‐cleavage. Of particular interest for a mechanistic proposal are structural distinctions observed in the active sites that concern the conformation of the U‐A cleavage site dinucleotide (in‐line alignment of the attacking 2′‐O nucleophile to the to‐be‐cleaved P—O5′ bond versus suboptimal alignments) as well as the presence/absence of Mg2+ ions at the scissile phosphate. All structures support the notion that an active site guanine and the conserved adenine at the cleavage site are important contributors to cleavage chemistry, likely being involved in general acid base catalysis. Evidence for innersphere coordination of a Mg2+ ion to the pro‐S nonbridging oxygen of the scissile phosphate stems from two of the four crystal structures. Together with the finding of thio/rescue effects for phosphorothioate substrates, this suggests the participation of divalent ions in the overall catalytic strategy employed by twister ribozymes. In this context, it is notable that twister retains wild‐type activity when the phylogenetically conserved stem P1 is deleted, able to cleave a single nucleotide only. WIREs RNA 2017, 8:e1402. doi: 10.1002/wrna.1402 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Jennifer Gebetsberger
- Institute of Organic Chemistry, Leopold-Franzens University and Center of Molecular Biosciences Innsbruck CMBI, Innsbruck, Austria
| | - Ronald Micura
- Institute of Organic Chemistry, Leopold-Franzens University and Center of Molecular Biosciences Innsbruck CMBI, Innsbruck, Austria
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25
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Xia R, Sun LP, Qu GR. The synthesis of nebularine and its analogs via oxidative desulfuration in aqueous nitric acid. PHOSPHORUS SULFUR 2016. [DOI: 10.1080/10426507.2016.1225057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Ran Xia
- School of Chemistry and Chemical Engineering, School of Life Science and Technology, Xinxiang University, Xinxiang City, Henan Province, China
| | - Li-Ping Sun
- School of Chemistry and Chemical Engineering, School of Life Science and Technology, Xinxiang University, Xinxiang City, Henan Province, China
| | - Gui-Rong Qu
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang City, Henan Province, China
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26
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Wu RR, Chen Y, Rodgers MT. Mechanisms and energetics for N-glycosidic bond cleavage of protonated 2'-deoxyguanosine and guanosine. Phys Chem Chem Phys 2016; 18:2968-80. [PMID: 26740232 DOI: 10.1039/c5cp05738h] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Experimental and theoretical investigations suggest that hydrolysis of N-glycosidic bonds generally involves a concerted SN2 or a stepwise SN1 mechanism. While theoretical investigations have provided estimates for the intrinsic activation energies associated with N-glycosidic bond cleavage reactions, experimental measurements to validate the theoretical studies remain elusive. Here we report experimental investigations for N-glycosidic bond cleavage of the protonated guanine nucleosides, [dGuo+H](+) and [Guo+H](+), using threshold collision-induced dissociation (TCID) techniques. Two major dissociation pathways involving N-glycosidic bond cleavage, resulting in production of protonated guanine or the elimination of neutral guanine are observed in competition for both [dGuo+H](+) and [Guo+H](+). The detailed mechanistic pathways for the N-glycosidic bond cleavage reactions observed are mapped via electronic structure calculations. Excellent agreement between the measured and B3LYP calculated activation energies and reaction enthalpies for N-glycosidic bond cleavage of [dGuo+H](+) and [Guo+H](+) in the gas phase is found indicating that these dissociation pathways involve stepwise E1 mechanisms in analogy to the SN1 mechanisms that occur in the condensed phase. In contrast, MP2 is found to significantly overestimate the activation energies and slightly overestimate the reaction enthalpies. The 2'-hydroxyl substituent is found to stabilize the N-glycosidic bond such that [Guo+H](+) requires ∼25 kJ mol(-1) more than [dGuo+H](+) to activate the glycosidic bond.
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Affiliation(s)
- R R Wu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - Yu Chen
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
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