1
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Sattler C, Ceylan B, Hoffmann L, Juric A, Kraus J, Marandi S, Shahnazari A, Rühl M. Sequence confirmation of synthetic DNA exceeding 100 nucleotides using restriction enzyme mediated digestion combined with high-resolution tandem mass spectrometry. J Pharm Biomed Anal 2024; 245:116180. [PMID: 38703748 DOI: 10.1016/j.jpba.2024.116180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 04/11/2024] [Accepted: 04/23/2024] [Indexed: 05/06/2024]
Abstract
Oligonucleotides have emerged as important therapeutic options for inherited diseases. In recent years, RNA therapeutics, especially mRNA, have been pushed to the market. Analytical methods for these molecules have been published extensively in the last few years. Notably, mass spectrometry has proven as a state-of-the-art quality control method. For RNA based therapeutics, numerous methods are available, while DNA therapeutics lack of suitable MS-based methods when it comes to molecules exceeding approximately 60 nucleotides. We present a method which combines the use of common restriction enzymes and short enzyme-directing oligonucleotides to generate DNA digestion products with the advantages of high-resolution tandem mass spectrometry. The instrumentation includes ion pair reverse phase chromatography coupled to a time-of-flight mass spectrometer with a collision induced dissociation (CID) for sequence analysis. Utilizing this approach, we increased the sequence coverage from 23.3% for a direct CID-MS/MS experiment of a 100 nucleotide DNA molecule to 100% sequence coverage using the restriction enzyme mediated approach presented in this work. This approach is suitable for research and development and quality control purposes in a regulated environment, which makes it a versatile tool for drug development.
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Affiliation(s)
| | - Burak Ceylan
- BioSpring GmbH, Alt-Fechenheim 34, Frankfurt am Main 60386, Germany
| | - Luisa Hoffmann
- BioSpring GmbH, Alt-Fechenheim 34, Frankfurt am Main 60386, Germany
| | - Andela Juric
- BioSpring GmbH, Alt-Fechenheim 34, Frankfurt am Main 60386, Germany
| | - Julia Kraus
- BioSpring GmbH, Alt-Fechenheim 34, Frankfurt am Main 60386, Germany
| | - Shima Marandi
- BioSpring GmbH, Alt-Fechenheim 34, Frankfurt am Main 60386, Germany
| | - Aref Shahnazari
- BioSpring GmbH, Alt-Fechenheim 34, Frankfurt am Main 60386, Germany
| | - Michael Rühl
- BioSpring GmbH, Alt-Fechenheim 34, Frankfurt am Main 60386, Germany.
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2
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Sun RX, Zuo MQ, Zhang JS, Dong MQ. Charge-State-Dependent Collision-Induced Dissociation Behaviors of RNA Oligonucleotides via High-Resolution Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023. [PMID: 37463304 DOI: 10.1021/jasms.3c00073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Mass spectrometry (MS)-based analysis of RNA oligonucleotides (oligos) plays an increasingly important role in the development of RNA therapeutics and epitranscriptomics research. However, MS fragmentation behaviors of RNA oligomers are understood insufficiently. Herein, we characterized the negative-ion-mode fragmentation behaviors of 26 synthetic RNA oligos containing four to eight nucleotides using collision-induced dissociation (CID) on a high-resolution, accurate-mass instrument. We found that in CID spectra acquired under the normalized collision energy (NCE) of 35%, approximately 70% of the total peak intensity was attributed to sequencing ions (a-B, a, b, c, d, w, x, y, z), around 25% of the peak intensity came from precursor ions that experienced complete or partial loss of a nucleobase in the form of either a neutral or an anion, and the remainder were internal ions and anionic nucleobases. The top five sequencing ions were the y, c, w, a-B, and a ions. Furthermore, we observed that CID fragmentation behaviors of RNA oligos were significantly impacted by their precursor charge. Specifically, when the precursors had a charge from 1- to 5-, the fractional intensity of sequencing ions decreased, while that of precursors that underwent either neutral or charged losses of a nucleobase increased. Additionally, we found that RNA oligos containing 3'-U tended to produce precursors with HNCO and/or NCO- losses, which presumably corresponded to isocyanic acid and cyanate anion, respectively. These findings provide valuable insights for better comprehending the mechanism behind RNA fragmentation by MS/MS, thereby facilitating the future automated identification of RNA oligos based on their CID spectra in a more efficient manner.
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Affiliation(s)
- Rui-Xiang Sun
- National Institute of Biological Sciences, Beijing 102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 100084, China
| | - Mei-Qing Zuo
- National Institute of Biological Sciences, Beijing 102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 100084, China
| | - Ji-Shuai Zhang
- National Institute of Biological Sciences, Beijing 102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 100084, China
| | - Meng-Qiu Dong
- National Institute of Biological Sciences, Beijing 102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 100084, China
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3
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Investigation of the Influence of Charge State and Collision Energy on Oligonucleotide Fragmentation by Tandem Mass Spectrometry. Molecules 2023; 28:molecules28031169. [PMID: 36770836 PMCID: PMC9921629 DOI: 10.3390/molecules28031169] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/20/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023] Open
Abstract
Due to the increasing pharmaceutical interest of oligonucleotides, for example in antisense therapy and vaccines, their analytical characterization is of fundamental importance due to their complex structure. For this purpose, mass spectrometry is a viable tool for structural studies of nucleic acids. Structural information regarding the primary sequence of a nucleic acid can reliably be gained via tandem mass spectrometry (MSMS) fragmentation. In this work, we present the characteristic fragmentation behavior of short-chain oligonucleotides (15-35 nucleotides) with respect to the collision-induced dissociation (CID) voltage used. The relationship and influence of the length of the oligonucleotide and its charge state is also discussed. The results presented here can be helpful for estimating the required fragmentation energies of short-chain oligonucleotides and their sequencing.
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4
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Sutton JM, Kim J, El Zahar NM, Bartlett MG. BIOANALYSIS AND BIOTRANSFORMATION OF OLIGONUCLEOTIDE THERAPEUTICS BY LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY. MASS SPECTROMETRY REVIEWS 2021; 40:334-358. [PMID: 32588492 DOI: 10.1002/mas.21641] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 05/05/2020] [Accepted: 05/28/2020] [Indexed: 06/11/2023]
Abstract
Since 2016, eight new oligonucleotide therapies have been approved which has led to increased interest in oligonucleotide analysis. There is a particular need for powerful bioanalytical tools to study the metabolism and biotransformation of these molecules. This review provides the background on the biological basis of these molecules as currently used in therapies. The article also reviews the current state of analytical methodology including state of the art sample preparation techniques, liquid chromatography-mass spectrometry methods, and the current limits of detection/quantitation. Finally, the article summarizes the challenges in oligonucleotide bioanalysis and provides future perspectives for this emerging field. © 2020 John Wiley & Sons Ltd.
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Affiliation(s)
- James Michael Sutton
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
| | - Jaeah Kim
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
| | - Noha M El Zahar
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Organization of African Unity Street, Cairo, 11566, Egypt
| | - Michael G Bartlett
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
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5
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Zhang N, Shi S, Yuan X, Ni W, Wang X, Yoo B, Jia TZ, Li W, Zhang S. A General LC-MS-Based Method for Direct and De Novo Sequencing of RNA Mixtures Containing both Canonical and Modified Nucleotides. Methods Mol Biol 2021; 2298:261-277. [PMID: 34085251 DOI: 10.1007/978-1-0716-1374-0_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mass spectrometry (MS)-based sequencing has advantages in direct sequencing of RNA, compared to cDNA-based RNA sequencing methods, as it is completely independent of enzymes and base complementarity errors in sample preparation. In addition, it allows for sequencing of different RNA modifications in a single study, rather than just one specific modification type per study. However, many technical challenges remain in de novo MS sequencing of RNA, making it difficult to MS sequence mixed RNAs or to differentiate isomeric modifications such as pseudouridine (Ψ) from uridine (U). Our recent study incorporates a two-dimensional hydrophobic end labeling strategy into MS-based sequencing (2D-HELS MS Seq) to systematically address the current challenges in MS sequencing of RNA, making it possible to directly and de novo sequence purified single RNA and mixed RNA containing both canonical and modified nucleotides. Here, we describe the method to sequence representative single-RNA and mixed-RNA oligonucleotides, each with a different sequence and/or containing modified nucleotides such as Ψ and 5-methylcytosine (m5C), using 2D-HELS MS Seq.
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Affiliation(s)
- Ning Zhang
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY, USA.,Department of Chemical Engineering, Columbia University, New York, NY, USA
| | - Shundi Shi
- Department of Chemical Engineering, Columbia University, New York, NY, USA
| | - Xiaohong Yuan
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY, USA
| | - Wenhao Ni
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY, USA
| | - Xuanting Wang
- Department of Chemical Engineering, Columbia University, New York, NY, USA
| | - Barney Yoo
- Department of Chemistry, Hunter College, City University of New York, New York, NY, USA
| | - Tony Z Jia
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan.,Blue Marble Space Institute of Science, Seattle, WA, USA
| | - Wenjia Li
- Department of Computer Science, New York Institute of Technology, New York, NY, USA
| | - Shenglong Zhang
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY, USA.
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6
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Gu H, Ma K, Zhao W, Qiu L, Xu W. A general purpose MALDI matrix for the analyses of small organic, peptide and protein molecules. Analyst 2021; 146:4080-4086. [PMID: 34052846 DOI: 10.1039/d1an00474c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) has been widely applied for the analysis of large biomolecules. The emergence of inorganic material substrates and new organic matrices extends the use of MALDI MS for small molecule analyses. However, there are usually preferred matrices for different types of analytes. Here, an organic compound, 4-hydroxy-3-nitrobenzonitrile, was found to be a general purpose matrix for the analyses of small organic, peptide and protein molecules. In particular, 4-hydroxy-3-nitrobenzonitrile has a strong UV absorption property, and it provides a clean background in the low mass range. Its analytical performances as a UV-laser matrix were demonstrated for different types of analytes, including organic drugs, peptides, proteins, mouse brain tissue and bacteria. Compared with commercial matrices, this new matrix has better performances when analyzing small molecules, such as drugs, peptides and lipids, while it has similar performances when analyzing proteins.
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Affiliation(s)
- Hao Gu
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
| | - Kang Ma
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
| | - Weiqian Zhao
- School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China
| | - Lirong Qiu
- School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China
| | - Wei Xu
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
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7
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Du X, Cheng X, Li W, Ge Z, Zhong C, Fan C, Gu H. Engineering Allosteric Ribozymes to Detect Thiamine Pyrophosphate in Whole Blood. Anal Chem 2021; 93:4277-4284. [PMID: 33635634 DOI: 10.1021/acs.analchem.0c05276] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thiamine deficiency contributes to several human diseases including Alzheimer's. As its biologically active form, thiamine pyrophosphate (TPP) has been considered as a potential biomarker for Alzheimer's disease (AD) based on several clinical reports that apparently lower blood TPP levels were found in patients with mild cognitive impairment to AD. However, highly sensitive and high-throughput detection of TPP in biological fluids remains an analytical challenge. Here, we report engineering RNA-based sensors to quantitatively measure TPP concentrations in whole blood samples with a detection limit down to a few nM. By fusing a TPP-specific aptamer with the hammerhead ribozyme for in vitro selection, we isolated an allosteric ribozyme with an EC50 value (68 nM) similar to the aptamer's KD value (50 nM) for TPP, which for the first time demonstrates the possibility to maintain the effector binding affinity of the aptamer in such engineered allosteric RNA constructs. Meanwhile, we developed a new blood sample preparation protocol to be compatible with RNA. By coupling the TPP-induced ribozyme cleavage event with isothermal amplification, we achieved fluorescence monitoring of whole blood TPP levels through the "mix-and-read" operation with high-throughput potential. We expect that the engineered TPP-sensing RNAs will facilitate clinical research on AD as well as other thiamine-related diseases.
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Affiliation(s)
- Xinyu Du
- Fudan University Shanghai Cancer Center, and the Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Stomatological Hospital, Fudan University, Shanghai 200032, China.,Department of Neurology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xiaoqin Cheng
- Department of Neurology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Wei Li
- Fudan University Shanghai Cancer Center, and the Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Stomatological Hospital, Fudan University, Shanghai 200032, China.,Department of Neurology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Zhilei Ge
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chunjiu Zhong
- Department of Neurology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Chunhai Fan
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hongzhou Gu
- Fudan University Shanghai Cancer Center, and the Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Stomatological Hospital, Fudan University, Shanghai 200032, China.,Department of Neurology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China
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8
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Pourshahian S. THERAPEUTIC OLIGONUCLEOTIDES, IMPURITIES, DEGRADANTS, AND THEIR CHARACTERIZATION BY MASS SPECTROMETRY. MASS SPECTROMETRY REVIEWS 2021; 40:75-109. [PMID: 31840864 DOI: 10.1002/mas.21615] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Oligonucleotides are an emerging class of drugs that are manufactured by solid-phase synthesis. As a chemical class, they have unique product-related impurities and degradants, characterization of which is an essential step in drug development. The synthesis cycle, impurities produced during the synthesis and degradation products are presented and discussed. The use of liquid chromatography combined with mass spectrometry for characterization and quantification of product-related impurities and degradants is reviewed. In addition, sequence determination of oligonucleotides by gas-phase fragmentation and indirect mass spectrometric methods is discussed. © 2019 John Wiley & Sons Ltd. Mass Spec Rev.
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Affiliation(s)
- Soheil Pourshahian
- Janssen Pharmaceutical Companies of Johnson & Johnson, South San Francisco, CA, 94080
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9
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Zhang N, Shi S, Jia TZ, Ziegler A, Yoo B, Yuan X, Li W, Zhang S. A general LC-MS-based RNA sequencing method for direct analysis of multiple-base modifications in RNA mixtures. Nucleic Acids Res 2020; 47:e125. [PMID: 31504795 PMCID: PMC6847078 DOI: 10.1093/nar/gkz731] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/07/2019] [Accepted: 08/15/2019] [Indexed: 12/31/2022] Open
Abstract
A complete understanding of the structural and functional potential of RNA requires understanding of chemical modifications and non-canonical bases; this in turn requires advances in current sequencing methods to be able to sequence not only canonical ribonucleotides, but at the same time directly sequence these non-standard moieties. Here, we present the first direct and modification type-independent RNA sequencing method via introduction of a 2-dimensional hydrophobic end-labeling strategy into traditional mass spectrometry-based sequencing (2D HELS MS Seq) to allow de novo sequencing of RNA mixtures and enhance sample usage efficiency. Our method can directly read out the complete sequence, while identifying, locating, and quantifying base modifications accurately in both single and mixed RNA samples containing multiple different modifications at single-base resolution. Our method can also quantify stoichiometry/percentage of modified RNA versus its canonical counterpart RNA, simulating a real biological sample where modifications exist but may not be 100% at a particular site in the RNA. This method is a critical step towards fully sequencing real complex cellular RNA samples of any type and containing any modification type and can also be used in the quality control of modified therapeutic RNAs.
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Affiliation(s)
- Ning Zhang
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY 10023, USA.,Department of Chemical Engineering, Columbia University, New York, NY 10027, USA
| | - Shundi Shi
- Department of Chemical Engineering, Columbia University, New York, NY 10027, USA
| | - Tony Z Jia
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan.,Blue Marble Space Institute of Science, Seattle, WA 98154, USA
| | - Ashley Ziegler
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY 10023, USA
| | - Barney Yoo
- Department of Chemistry, Hunter College, City University of New York, New York, NY 10065, USA
| | - Xiaohong Yuan
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY 10023, USA
| | - Wenjia Li
- Department of Computer Science, New York Institute of Technology, New York, NY 10023, USA
| | - Shenglong Zhang
- Department of Biological and Chemical Sciences, New York Institute of Technology, New York, NY 10023, USA
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10
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Pourshahian S, Gryaznov SM. Sequencing of Phosphoramidate Oligonucleotides by Acid Hydrolysis and Mass Spectrometry. Anal Chem 2019; 91:11154-11161. [PMID: 31386344 DOI: 10.1021/acs.analchem.9b01858] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hydrolysis of N3'-P5' phosphoramidate and thiophosphoramidate oligonucleotides with 0.1% formic acid leads to the cleavage of the 3' N-P bond and generates two products, one of which contains a 5'-phosphate. Analysis of the hydrolytic products by liquid chromatography, coupled with mass spectrometry, reveals the mass ladder from both termini, which is used to determine the sequence. While acid hydrolysis does not result in depurination, internal fragments especially in the low mass range are detected. The method is applied to DNA and RNA analogues with and without modifications at the 2'-position. This approach enables rapid sequence confirmation of synthetic phosphoramidate oligonucleotides for quality control as well as denovo sequencing.
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Affiliation(s)
- Soheil Pourshahian
- Janssen Pharmaceutical Companies of Johnson & Johnson , South San Francisco , California 94080 , United States
| | - Sergei M Gryaznov
- Janssen Pharmaceutical Companies of Johnson & Johnson , South San Francisco , California 94080 , United States
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11
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Studzińska S. Review on investigations of antisense oligonucleotides with the use of mass spectrometry. Talanta 2017; 176:329-343. [PMID: 28917758 DOI: 10.1016/j.talanta.2017.08.025] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/03/2017] [Accepted: 08/07/2017] [Indexed: 11/17/2022]
Abstract
Antisense oligonucleotides have been investigated as potential drugs for years. They inhibit target gene or protein expression. The present review summarizes their modifications, modes of action, and applications of liquid chromatography coupled with mass spectrometry for qualitative and quantitative analysis of these compounds. The most recent reports on a given topic were given prominence, while some early studies were reviewed in order to provide a theoretical background. The present review covers the issues of using ion-exchange chromatography, ion-pair reversed-phase high performance liquid chromatography and hydrophilic interaction chromatography for the separation of antisense oligonucleotides. The application of mass spectrometry was described with regard to the ionization type used for the determination of these potential therapeutics. Moreover, the current approaches and applications of mass spectrometry for quantitative analysis of antisense oligonucleotides and their metabolites as well as their impurities during in vitro and in vivo studies were discussed. Finally, certain conclusions and perspectives on the determination of therapeutic oligonucleotides in various samples were briefly described.
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Affiliation(s)
- Sylwia Studzińska
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, 7 Gagarin Str., PL-87-100 Toruń, Poland.
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12
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MicroRNA MultiTool: A Software for Identifying Modified and Unmodified Human microRNA Using Mass Spectrometry. Noncoding RNA 2017; 3:ncrna3010013. [PMID: 29657285 PMCID: PMC5832007 DOI: 10.3390/ncrna3010013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 03/10/2017] [Accepted: 03/10/2017] [Indexed: 12/11/2022] Open
Abstract
microRNA (miRNA) are short endogenous non-coding RNA that play a crucial role in post-transcriptional gene regulation and have been implicated in the initiation and progression of 160+ human diseases. Excellent analytical methods have been developed for the measurement of miRNA by mass spectrometry. However, interpretation of mass spectrometric data has been an incapacitating bottleneck in miRNA identification. This study details the development of MicroRNA MultiTool, a software for the identification of miRNA from mass spectrometric data. The software includes capabilities such as miRNA search and mass calculator, modified miRNA mass calculator, and miRNA fragment search. MicroRNA MultiTool bridges the gap between experimental data and identification of miRNA by providing a rapid means of mass spectrometric data interpretation.
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13
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Goto R, Miyakawa S, Inomata E, Takami T, Yamaura J, Nakamura Y. De novo sequencing of highly modified therapeutic oligonucleotides by hydrophobic tag sequencing coupled with LC-MS. JOURNAL OF MASS SPECTROMETRY : JMS 2017; 52:78-93. [PMID: 27935159 DOI: 10.1002/jms.3902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 11/23/2016] [Accepted: 11/24/2016] [Indexed: 06/06/2023]
Abstract
Correct sequences are prerequisite for quality control of therapeutic oligonucleotides. However, there is no definitive method available for determining sequences of highly modified therapeutic RNAs, and thereby, most of the oligonucleotides have been used clinically without direct sequence determination. In this study, we developed a novel sequencing method called 'hydrophobic tag sequencing'. Highly modified oligonucleotides are sequenced by partially digesting oligonucleotides conjugated with a 5'-hydrophobic tag, followed by liquid chromatography-mass spectrometry analysis. 5'-Hydrophobic tag-printed fragments (5'-tag degradates) can be separated in order of their molecular masses from tag-free oligonucleotides by reversed-phase liquid chromatography. As models for the sequencing, the anti-VEGF aptamer (Macugen) and the highly modified 38-mer RNA sequences were analyzed under blind conditions. Most nucleotides were identified from the molecular weight of hydrophobic 5'-tag degradates calculated from monoisotopic mass in simple full mass data. When monoisotopic mass could not be assigned, the nucleotide was estimated using the molecular weight of the most abundant mass. The sequences of Macugen and 38-mer RNA perfectly matched the theoretical sequences. The hydrophobic tag sequencing worked well to obtain simple full mass data, resulting in accurate and clear sequencing. The present study provides for the first time a de novo sequencing technology for highly modified RNAs and contributes to quality control of therapeutic oligonucleotides. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- R Goto
- Bioanalysis Business Department, CMIC Pharma Science Co., Ltd., 17-18, Nakahata-cho, Nishiwaki-shi, Hyogo, 677-0032, Japan
| | - S Miyakawa
- Exploratory Research Laboratory, RIBOMIC Inc., 3-16-13, Shirokanedai, Minato-ku, Tokyo, 108-0071, Japan
| | - E Inomata
- Exploratory Research Laboratory, RIBOMIC Inc., 3-16-13, Shirokanedai, Minato-ku, Tokyo, 108-0071, Japan
| | - T Takami
- Bioanalysis Department, CMIC, Inc., Hoffman Estates, Illinois, 60192-3702, USA
| | - J Yamaura
- Exploratory Research Laboratory, RIBOMIC Inc., 3-16-13, Shirokanedai, Minato-ku, Tokyo, 108-0071, Japan
| | - Y Nakamura
- Exploratory Research Laboratory, RIBOMIC Inc., 3-16-13, Shirokanedai, Minato-ku, Tokyo, 108-0071, Japan
- Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan
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14
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Recent Advances in the Characterization and Analysis of Therapeutic Oligonucleotides by Analytical Separation Methods Coupling with Mass Spectrometry. ADVANCES IN CHROMATOGRAPHY 2016. [DOI: 10.1201/9781315370385-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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15
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Björkbom A, Lelyveld VS, Zhang S, Zhang W, Tam CP, Blain JC, Szostak JW. Bidirectional Direct Sequencing of Noncanonical RNA by Two-Dimensional Analysis of Mass Chromatograms. J Am Chem Soc 2015; 137:14430-8. [PMID: 26495937 PMCID: PMC7547889 DOI: 10.1021/jacs.5b09438] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Mass spectrometry (MS) is a powerful technique for characterizing noncanonical nucleobases and other chemical modifications in small RNAs, yielding rich chemical information that is complementary to high-throughput indirect sequencing. However, mass spectra are often prohibitively complex when fragment ions are analyzed following either solution phase hydrolysis or gas phase fragmentation. For all but the simplest cases, ions arising from multiple fragmentation events, alternative fragmentation pathways, and diverse salt adducts frequently obscure desired single-cut fragment ions. Here we show that it is possible to take advantage of predictable regularities in liquid chromatographic (LC) separation of optimized RNA digests to greatly simplify the interpretation of complex MS data. A two-dimensional analysis of extracted compound chromatograms permits straightforward and robust de novo sequencing, using a novel Monte Carlo algorithm that automatically generates bidirectional paired-end reads, pinpointing the position of modified nucleotides in a sequence. We demonstrate that these advances permit routine LC-MS sequencing of RNAs containing noncanonical nucleotides, and we furthermore examine the applicability of this approach to the study of oligonucleotides containing artificial modifications as well as those commonly observed in post-transcriptionally modified RNAs.
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Affiliation(s)
- Anders Björkbom
- Howard Hughes Medical Institute , Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , Boston, Massachusetts 02115, United States.,Åbo Akademi University , Department of Biosciences, Artillerigatan 6, FI-20520 Åbo, Finland
| | - Victor S Lelyveld
- Howard Hughes Medical Institute , Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , Boston, Massachusetts 02115, United States
| | - Shenglong Zhang
- Howard Hughes Medical Institute , Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
| | - Weicheng Zhang
- Howard Hughes Medical Institute , Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States
| | - Chun Pong Tam
- Howard Hughes Medical Institute , Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States
| | - J Craig Blain
- Howard Hughes Medical Institute , Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
| | - Jack W Szostak
- Howard Hughes Medical Institute , Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.,Department of Genetics, Harvard Medical School , Boston, Massachusetts 02115, United States
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16
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Riml C, Glasner H, Rodgers MT, Micura R, Breuker K. On the mechanism of RNA phosphodiester backbone cleavage in the absence of solvent. Nucleic Acids Res 2015; 43:5171-81. [PMID: 25904631 PMCID: PMC4446422 DOI: 10.1093/nar/gkv288] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 03/24/2015] [Indexed: 12/18/2022] Open
Abstract
Ribonucleic acid (RNA) modifications play an important role in the regulation of gene expression and the development of RNA-based therapeutics, but their identification, localization and relative quantitation by conventional biochemical methods can be quite challenging. As a promising alternative, mass spectrometry (MS) based approaches that involve RNA dissociation in ‘top-down’ strategies are currently being developed. For this purpose, it is essential to understand the dissociation mechanisms of unmodified and posttranscriptionally or synthetically modified RNA. Here, we have studied the effect of select nucleobase, ribose and backbone modifications on phosphodiester bond cleavage in collisionally activated dissociation (CAD) of positively and negatively charged RNA. We found that CAD of RNA is a stepwise reaction that is facilitated by, but does not require, the presence of positive charge. Preferred backbone cleavage next to adenosine and guanosine in CAD of (M+nH)n+ and (M−nH)n− ions, respectively, is based on hydrogen bonding between nucleobase and phosphodiester moieties. Moreover, CAD of RNA involves an intermediate that is sufficiently stable to survive extension of the RNA structure and intramolecular proton redistribution according to simple Coulombic repulsion prior to backbone cleavage into c and y ions from phosphodiester bond cleavage.
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Affiliation(s)
- Christian Riml
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Heidelinde Glasner
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - M T Rodgers
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202-3489, United States
| | - 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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Lin Z, Zheng J, Bian W, Cai Z. CuFe2O4 magnetic nanocrystal clusters as a matrix for the analysis of small molecules by negative-ion matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Analyst 2015; 140:5287-94. [DOI: 10.1039/c5an00625b] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
CuFe2O4 MNCs were proposed as a new matrix for negative ion MALDI-TOF MS, which exhibited interference-free background, high salt tolerance and good reproducibility for analysis of small molecules.
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Affiliation(s)
- Zian Lin
- Partner State Key Laboratory of Environmental and Biological Analysis
- Department of Chemistry
- Hong Kong Baptist University
- Kowloon Tong
- P. R. China
| | - Jiangnan Zheng
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety
- College of Chemistry
- Fuzhou University
- Fuzhou
- China
| | - Wei Bian
- Partner State Key Laboratory of Environmental and Biological Analysis
- Department of Chemistry
- Hong Kong Baptist University
- Kowloon Tong
- P. R. China
| | - Zongwei Cai
- Partner State Key Laboratory of Environmental and Biological Analysis
- Department of Chemistry
- Hong Kong Baptist University
- Kowloon Tong
- P. R. China
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18
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Thomas A, Walpurgis K, Delahaut P, Kohler M, Schänzer W, Thevis M. Detection of small interfering RNA (siRNA) by mass spectrometry procedures in doping controls. Drug Test Anal 2013; 5:853-60. [PMID: 23913913 DOI: 10.1002/dta.1519] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 07/03/2013] [Accepted: 07/06/2013] [Indexed: 01/26/2023]
Abstract
Uncovering manipulation of athletic performance via small interfering (si)RNA is an emerging field in sports drug testing. Due to the potential to principally knock down every target gene in the organism by means of the RNA interference pathway, this facet of gene doping has become a realistic scenario. In the present study, two distinct model siRNAs comprising 21 nucleotides were designed as double strands which were perfect counterparts to a sequence of the respective messenger RNA coding the muscle regulator myostatin of Rattus norvegicus. Several modified nucleotides were introduced in both the sense and the antisense strand comprising phosphothioates, 2'-O-methylation, 2'-fluoro-nucleotides, locked nucleic acids and a cholesterol tag at the 3'-end. The model siRNAs were applied to rats at 1 mg/kg (i.v.) and blood as well as urine samples were collected. After isolation of the RNA by means of a RNA purification kit, the target analytes were detected by liquid chromatography - high resolution/high accuracy mass spectrometry (LC-HRMS). Analytes were detected as modified nucleotides after alkaline hydrolysis, as intact oligonucleotide strands (top-down) and by means of denaturing SDS-PAGE analysis. The gel-separated siRNA was further subjected to in-gel hydrolysis with different RNases and subsequent identification of the fragments by untargeted LC-HRMS analysis (bottom-up, 'experimental RNomics'). Combining the results of all approaches, the identification of several 3'-truncated urinary metabolites was accomplished and target analytes were detected up to 24 h after a single administration. Simultaneously collected blood samples yielded no promising results. The methods were validated and found fit-for-purpose for doping controls.
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Affiliation(s)
- Andreas Thomas
- Center for Preventive Doping Research and Institute of Biochemistry, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany
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19
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Hwang HJ, Nam J, Yang SI, Kwon JH, Oh HB. MALDI-TOF Analysis of Polyhexamethylene Guanidine (PHMG) Oligomers Used as a Commercial Antibacterial Humidifier Disinfectant. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.6.1708] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Ma R, Lu M, Ding L, Ju H, Cai Z. Surface-assisted laser desorption/ionization mass spectrometric detection of biomolecules by using functional single-walled carbon nanohorns as the matrix. Chemistry 2012; 19:102-8. [PMID: 23239539 DOI: 10.1002/chem.201202838] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Indexed: 01/21/2023]
Abstract
A surface-assisted laser desorption/ionization time-of-flight mass spectrometric (SALDI-TOF MS) method was developed for the analysis of small biomolecules by using functional single-walled carbon nanohorns (SWNHs) as matrix. The functional SWNHs could transfer energy to the analyte under laser irradiation for accelerating its desorption and ionization, which led to low matrix effect, avoided fragmentation of the analyte, and provided high salt tolerance. Biomolecules including amino acids, peptides, and fatty acids could successfully be analyzed with about 3- and 5-fold higher signals than those obtained using conventional matrix. By integrating the advantages of SWNHs and the recognition ability of aptamers, a selective approach was proposed for simultaneous capture, enrichment, ionization, and MS detection of adenosine triphosphate (ATP). This method showed a greatly improved detection limit (1.0 μM) for the analysis of ATP in complex biological samples. This newly designed protocol not only opened a new application of SWNHs, but also offered a new technique for selective MS analysis of biomolecules based on aptamer recognition systems.
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Affiliation(s)
- Rongna Ma
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China
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21
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Shimizu H, Jinno F, Morohashi A, Yamazaki Y, Yamada M, Kondo T, Asahi S. Application of high-resolution ESI and MALDI mass spectrometry to metabolite profiling of small interfering RNA duplex. JOURNAL OF MASS SPECTROMETRY : JMS 2012; 47:1015-1022. [PMID: 22899510 DOI: 10.1002/jms.3054] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We investigated the application of a high-resolution Orbitrap mass spectrometer equipped with an electrospray ionization (ESI) source and a matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometer to the metabolite profiling of a model small interfering RNA (siRNA) duplex TSR#34 and compared their functions and capabilities. TSR#34 duplex was incubated in human serum in vitro, and the duplex and its metabolites were then purified by ion exchange chromatography in order to remove the biological matrices. The fraction containing the siRNA duplex and its metabolites was collected and desalted and then subjected to high-performance liquid chromatography (HPLC) equipped with a reversed phase column. The siRNA and its metabolites were separated into single strands by elevated chromatographic temperature and analyzed using the ESI-Orbitrap or the MALDI-TOF mass spectrometer. Using this method, the 5' and/or 3' truncated metabolites of each strand were detected in the human serum samples. The ESI-Orbitrap mass spectrometer enabled differentiation between two possible RNA-based sequences, a monoisotopic molecular mass difference which was less than 2 Da, with an intrinsic mass resolving power. In-source decay (ISD) analysis using a MALDI-TOF mass spectrometer allowed the sequencing of the RNA metabolite with characteristic fragment ions, using 2,4-dihydroxyacetophenone (2,4-DHAP) as a matrix. The ESI-Orbitrap mass spectrometer provided the highest mass accuracy and the benefit of on-line coupling with HPLC for metabolite profiling. Meanwhile, the MALDI-TOF mass spectrometer, in combination with 2,4-DHAP, has the potential for the sequencing of RNA by ISD analysis. The combined use of these methods will be beneficial to characterize the metabolites of therapeutic siRNA compounds.
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MESH Headings
- Acetophenones/chemistry
- Base Sequence
- Chromatography, High Pressure Liquid
- Chromatography, Reverse-Phase
- Humans
- Models, Chemical
- Molecular Sequence Data
- RNA, Small Interfering/blood
- RNA, Small Interfering/chemistry
- Sequence Analysis, RNA
- Spectrometry, Mass, Electrospray Ionization/methods
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
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Affiliation(s)
- Hisao Shimizu
- Drug Metabolism and Pharmacokinetics Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Kanagawa, Japan.
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22
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Wurm JP, Griese M, Bahr U, Held M, Heckel A, Karas M, Soppa J, Wöhnert J. Identification of the enzyme responsible for N1-methylation of pseudouridine 54 in archaeal tRNAs. RNA (NEW YORK, N.Y.) 2012; 18:412-420. [PMID: 22274954 PMCID: PMC3285930 DOI: 10.1261/rna.028498.111] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 11/23/2011] [Indexed: 05/31/2023]
Abstract
tRNAs from all three kingdoms of life contain a variety of modified nucleotides required for their stability, proper folding, and accurate decoding. One prominent example is the eponymous ribothymidine (rT) modification at position 54 in the T-arm of eukaryotic and bacterial tRNAs. In contrast, in most archaea this position is occupied by another hypermodified nucleotide: the isosteric N1-methylated pseudouridine. While the enzyme catalyzing pseudouridine formation at this position is known, the pseudouridine N1-specific methyltransferase responsible for this modification has not yet been experimentally identified. Here, we present biochemical and genetic evidence that the two homologous proteins, Mja_1640 (COG 1901, Pfam DUF358) and Hvo_1989 (Pfam DUF358) from Methanocaldococcus jannaschii and Haloferax volcanii, respectively, are representatives of the methyltransferase responsible for this modification. However, the in-frame deletion of the pseudouridine N1-methyltransferase gene in H. volcanii did not result in a discernable phenotype in line with similar observations for knockouts of other T-arm methylating enzymes.
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Affiliation(s)
- Jan Philip Wurm
- Institut für Molekulare Biowissenschaften, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
| | - Marco Griese
- Institut für Molekulare Biowissenschaften, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
| | - Ute Bahr
- Institut für Pharmazeutische Chemie, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
| | - Martin Held
- Institut für Pharmazeutische Chemie, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
- Institut für Organische Chemie und Chemische Biologie, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
| | - Alexander Heckel
- Institut für Pharmazeutische Chemie, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
- Institut für Organische Chemie und Chemische Biologie, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
- Cluster of Excellence “Macromolecular complexes,” Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
| | - Michael Karas
- Institut für Pharmazeutische Chemie, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
- Cluster of Excellence “Macromolecular complexes,” Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
| | - Jörg Soppa
- Institut für Molekulare Biowissenschaften, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
| | - Jens Wöhnert
- Institut für Molekulare Biowissenschaften, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
- Cluster of Excellence “Macromolecular complexes,” Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
- Center for Biomolecular Magnetic Resonance (BMRZ), Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
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23
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Kohler M, Schänzer W, Thevis M. RNA interference for performance enhancement and detection in doping control. Drug Test Anal 2012; 3:661-7. [PMID: 22031503 DOI: 10.1002/dta.330] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
RNA interference represents a comparably new route of regulating and manipulating specific gene expression. Promising results were obtained in experimental therapies aim at the treatment of different kinds of diseases including cancer, diabetes mellitus or Dychenne muscular dystrophy. While studies on down-regulation efficiency are often performed by analyzing the regulated protein, the direct detection of small, interfering RNA molecules and antisense oligonucleotides is of great interest for the investigation of the metabolism and degradation and also for the detection of a putative misuse of these molecules in sports. Myostatin down-regulation was shown to result in increased performance and muscle growth and the regulation of several other proteins could be relevant for performance enhancement. This mini-review summarizes current approaches for the mass spectrometric analysis of siRNA and antisense oligonucleotides from biological matrices and the available data on biodistribution, metabolism, and half-life of relevant substances are discussed.
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Affiliation(s)
- Maxie Kohler
- Center for Preventive Doping Research/Institute of Biochemistry, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany
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24
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Affiliation(s)
- Feng Xian
- Department
of Chemistry and
Biochemistry, Florida State University,
95 Chieftain Way, Tallahassee, Florida 32310-4390, United States
| | - Christopher L. Hendrickson
- Department
of Chemistry and
Biochemistry, Florida State University,
95 Chieftain Way, Tallahassee, Florida 32310-4390, United States
- Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, 1800
East Paul Dirac Drive, Tallahassee, Florida 32310-4005, United States
| | - Alan G. Marshall
- Department
of Chemistry and
Biochemistry, Florida State University,
95 Chieftain Way, Tallahassee, Florida 32310-4390, United States
- Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, 1800
East Paul Dirac Drive, Tallahassee, Florida 32310-4005, United States
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25
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Zhao C, Yin R, Yin J, Zhang D, Wang H. Capillary monolithic bioreactor of immobilized snake venom phosphodiesterase for mass spectrometry based oligodeoxynucleotide sequencing. Anal Chem 2011; 84:1157-64. [PMID: 22208283 DOI: 10.1021/ac2029387] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A capillary monolithic bioreactor of snake venom phosphodiesterase (SVP) was constructed to generate different single-nucleotide mass ladders of oligodeoxynucleotides for mass spectrometry (MS)-based sequencing by immobilization. The immobilization of SVP in the porous silica monolith significantly enhances its stability for prolonged and repeated applications. The constructed capillary bioreactor has the advantages of handling (sub)microliter DNA samples and having good permeability. Benefiting from its good permeability, DNA solutions can be directly injected into the sequential digestion bioreactor simply by hand pushing or a low-pressure microinjection pump. Moreover, the immobilization of SVP facilitates the elimination or repression of the metal adducts of oligodeoxynucleotides, improving the analytical performance of MS sequencing. By the application of capillary bioreactor of immobilized SVP, the sequence-specific modification of single-stranded oligodeoxynucleotide induced by a ubiquitous pollutant acrolein (Acr) was identified, demonstrating its promising applications in identification of sequence-specific damage, which may further our understanding of DNA damage caused mutagenesis.
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Affiliation(s)
- Chao Zhao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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26
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Beverly MB. Applications of mass spectrometry to the study of siRNA. MASS SPECTROMETRY REVIEWS 2011; 30:979-998. [PMID: 20201110 DOI: 10.1002/mas.20260] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2008] [Revised: 08/13/2009] [Accepted: 08/13/2009] [Indexed: 05/28/2023]
Abstract
RNA interference (RNAi) has quickly become a well-established laboratory tool for regulating gene expression and is currently being explored for its therapeutic potential. The design and use of double-stranded RNA oligonucleotides as therapeutics to trigger the RNAi mechanism and a greater effort to understand the RNAi pathway itself is driving the development of analytical techniques that can characterize these oligonucleotides. Electrospray (ESI) and MALDI have been used routinely to analyze oligonucleotides and their ability to provide mass and sequence information has made them ideal for this application. Reviewed here is the work done to date on the use of ESI and MALDI for the study of RNAi oligonucleotides as well as the strategies and issues associated with siRNA analysis by mass spectrometry. While there is not a large body of literature on the specific application of mass spectrometry to RNAi, the work done in this area is a good demonstration of the range of experiments that can be conducted and the value that ESI and MALDI can provide to the RNAi field.
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Affiliation(s)
- Michael B Beverly
- RNA Therapeutics Department, Merck and Co., Inc., Boulder, CO 80301, USA.
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27
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McGinnis AC, Chen B, Bartlett MG. Chromatographic methods for the determination of therapeutic oligonucleotides. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 883-884:76-94. [PMID: 21945211 DOI: 10.1016/j.jchromb.2011.09.007] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 08/31/2011] [Accepted: 09/05/2011] [Indexed: 11/25/2022]
Abstract
Both DNA and RNA are being explored for their therapeutic potential against a wide range of diseases. As these new drugs emerge, new demands arise for the analysis and quantitation of these biomolecules. Pharmacokinetic and pharmacodynamic analysis requirements for drug approval place enormous challenges on the methods for analyzing these therapeutics. This review will focus on bioanalytical methods for DNA antisense and aptamers as well as small-interfering RNA (siRNA) therapeutics. Chromatography methods employing ultraviolet (UV), fluorescence and mass spectrometric (MS) detection along with matrix-assisted laser desorption/ionization (MALDI) will be covered. Sample preparation from biological matrices will be reviewed as well as metabolite analysis and identification. All of these techniques are important contributions toward oligonucleotide therapeutic development. They will also be important in microRNA (miRNA) biomarker discovery and RNomics in general, as more non-coding RNAs are inevitably discovered.
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Affiliation(s)
- A Cary McGinnis
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA 30602-2352, USA
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28
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Taucher M, Ganisl B, Breuker K. Identification, localization, and relative quantitation of pseudouridine in RNA by tandem mass spectrometry of hydrolysis products. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2011; 304:91-97. [PMID: 21960742 PMCID: PMC3180913 DOI: 10.1016/j.ijms.2010.05.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The constitutional isomers uridine (U) and pseudouridine (Ψ) cannot be distinguished from each other by simple mass measurements of RNA or its fragments because the conversion of U into Ψ is a "mass-silent" post-transcriptional modification. Here we propose a new mass spectrometry based method for identification, localization, and relative quantitation of Ψ in RNA consisting of ∼20 nucleotides that does not require chemical labeling. Our approach takes advantage of the different fragmentation behavior of uridine (N-glycosidic bond) and pseudouridine (C-glycosidic bond) residues in RNA upon collisionally activated dissociation.
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Affiliation(s)
| | | | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
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29
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Lu M, Lai Y, Chen G, Cai Z. Matrix interference-free method for the analysis of small molecules by using negative ion laser desorption/ionization on graphene flakes. Anal Chem 2011; 83:3161-9. [PMID: 21428301 DOI: 10.1021/ac2002559] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This work presents a new approach for the analysis of small molecules with direct negative ion laser desorption/ionization (LDI) on graphene flakes. A series of matrix interference-free mass spectra were obtained for the analysis of a wide range of small molecules including peptides, amino acids, fatty acids, as well as nucleosides and nucleotides. The mixture of analytes and graphene flakes suspension were directly pipetted onto a sample plate for LDI-time-of-flight mass spectrometry (TOFMS) analysis. Deprotonated monomeric species [M-H](-) ions were homogeneously obtained on uniform graphene flakes film when negative ion mode was applied. In positive ion mode, the analytes were detected in form of multiple adduct ions such as sodium adduct [M+Na](+), potassium adduct [M+K](+), double sodium adduct [M+2Na-H](+), double potassium adduct [M+2K-H](+), as well as sodium and potassium mixed adduct [M+Na+K-H](+). Better sensitivity and reproducibility were achieved in negative ion mode compared to positive ion mode. It is believed that the new method of matrix interference-free negative ion LDI on graphene flakes may be expanded for LDI-MS analysis of various small molecules.
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Affiliation(s)
- Minghua Lu
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Kowloon, Hong Kong SAR, China
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30
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Smith M. Characterisation of a modified oligonucleotide together with its synthetic impurities using accurate mass measurements. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:511-525. [PMID: 21259360 DOI: 10.1002/rcm.4886] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Oligonucleotide-based drugs are beginning to establish themselves within the pharmaceutical industry as important agents in the treatment of various disease states with the potential of exhibiting high specificity with gene targeted therapies. Recent studies regarding RNA interference has stimulated interest in this field. There are now an increasing number of oligonucleotide-based pharmaceutical products in various stages of clinical development for the treatment of life-threatening diseases. As a result, the production of synthetic oligonucleotides has become increasingly important, with both antisense and RNAi-related oligonucleotides under development as therapeutic agents. One potential drug candidate currently under development at GlaxoSmithKline, is a 2'-O-methyl phosphorothioate in which the non-bridging oxygens of the phosphate diester are replaced with sulphur. Oligonucleotides are polymeric sequences made from an array of nucleotides (RNA, DNA and their respective analogs) usually ranging from 20-100 nucleotides. The polar nature, low thermal stability, complexity and large molecular weights of oligonucleotides have posed a challenge for the analysis of oligonucleotides by mass spectrometry. This paper demonstrates the use of negative ion electrospray with a combination of high resolution and high mass accuracy for the characterisation of oligonucleotides with the intention of supporting an evidence of structure document for a regulatory submission. This is a new area within the mass spectrometry field and as such there is limited software amongst the instrument companies for the data processing for the analysis of these compounds. Therefore, many of the examples in the literature only use mass spectrometry to generate average molecular weights by deconvoluting the multiple charged states observed to give an average molecular weight; under-utilizing the capability of high-resolution instruments.
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Affiliation(s)
- Marco Smith
- GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire, UK.
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31
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Ganisl B, Taucher M, Riml C, Breuker K. Charge as you like! Efficient manipulation of negative ion net charge in electrospray ionization of proteins and nucleic acids. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2011; 17:333-343. [PMID: 22006635 DOI: 10.1255/ejms.1140] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Acidic proteins and nucleic acids such as RNA are most readily ionized in electrospray ionization (ESI) operated in negative-ion mode. The multiply deprotonated protein or RNA ions can be used as precursors in top- down mass spectrometry. Because the performance of the dissociation method used critically depends on precursor ion negative net charge, it is important that the extent of charging in ESI can be manipulated efficiently. We show here that (M - nH)(n-) ion net charge of proteins and RNA can be controlled efficiently by the addition of organic bases to the electrosprayed solution. Our study also highlights the fact that ion formation in ESI in negative mode is only poorly understood.
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32
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Gardner MW, Li N, Ellington AD, Brodbelt JS. Infrared multiphoton dissociation of small-interfering RNA anions and cations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:580-91. [PMID: 20129797 PMCID: PMC2847665 DOI: 10.1016/j.jasms.2009.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2009] [Revised: 12/21/2009] [Accepted: 12/22/2009] [Indexed: 05/13/2023]
Abstract
Infrared multiphoton dissociation (IRMPD) on a linear ion trap mass spectrometer is applied for the sequencing of small interfering RNA (siRNA). Both single-strand siRNAs and duplex siRNA were characterized by IRMPD, and the results were compared with that obtained by traditional ion trap-based collision induced dissociation (CID). The single-strand siRNA anions were observed to dissociate via cleavage of the 5' P-O bonds yielding c- and y-type product ions as well as undergo neutral base loss. Full sequence coverage of the siRNA anions was obtained by both IRMPD and CID. While the CID mass spectra were dominated by base loss ions, accounting for approximately 25% to 40% of the product ion current, these ions were eliminated through secondary dissociation by increasing the irradiation time in the IRMPD mass spectra to produce higher abundances of informative sequence ions. With longer irradiation times, however, internal ions corresponding to cleavage of two 5' P-O bonds began to populate the product ion mass spectra as well as higher abundances of [a - Base] and w-type ions. IRMPD of siRNA cations predominantly produced c- and y-type ions with minimal contributions of [a - Base] and w-type ions to the product ion current; the presence of only two complementary series of product ions in the IRMPD mass spectra simplified spectral interpretation. In addition, IRMPD produced high abundances of protonated nucleobases, [G + H](+), [A + H](+), and [C + H](+), which were not detected in the CID mass spectra due to the low-mass cut-off associated with conventional CID in ion traps. CID and IRMPD using short irradiation times of duplex siRNA resulted in strand separation, similar to the dissociation trends observed for duplex DNA. With longer irradiation times, however, the individual single-strands underwent secondary dissociation to yield informative sequence ions not obtained by CID.
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Affiliation(s)
- Myles W Gardner
- Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712-0165, USA
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Taucher M, Rieder U, Breuker K. Minimizing base loss and internal fragmentation in collisionally activated dissociation of multiply deprotonated RNA. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:278-85. [PMID: 19932627 DOI: 10.1016/j.jasms.2009.10.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 09/28/2009] [Accepted: 10/14/2009] [Indexed: 05/25/2023]
Abstract
In recent years, new classes of nonprotein-coding ribonucleic acids (ncRNAs) with important cellular functions have been discovered. Of particular interest for biomolecular research and pharmaceutical developments are small ncRNAs that are involved in gene regulation, such as small interfering RNAs (21-28 nt), pre-microRNAs (70-80 nt), or riboswitches (34-200 nt). De novo sequencing of RNA by top-down mass spectrometry has so far been limited to RNA consisting of up to approximately 20 nt. We report here complete sequence coverage for 34 nt RNA (10.9 kDa), along with 30 out of 32 possible complementary ion pairs from collisionally activated dissociation (CAD) experiments. The key to minimizing undesired base loss and internal fragmentation is to minimize the internal energy of fragment ions from primary backbone cleavage. This can be achieved by collisional cooling of primary fragment ions and selection of precursor ions of relatively low negative net charge (about -0.2/nt).
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Affiliation(s)
- Monika Taucher
- Institute of Organic Chemistry and Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
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Wurm JP, Meyer B, Bahr U, Held M, Frolow O, Kötter P, Engels JW, Heckel A, Karas M, Entian KD, Wöhnert J. The ribosome assembly factor Nep1 responsible for Bowen-Conradi syndrome is a pseudouridine-N1-specific methyltransferase. Nucleic Acids Res 2010; 38:2387-98. [PMID: 20047967 PMCID: PMC2853112 DOI: 10.1093/nar/gkp1189] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Nep1 (Emg1) is a highly conserved nucleolar protein with an essential function in ribosome biogenesis. A mutation in the human Nep1 homolog causes Bowen-Conradi syndrome-a severe developmental disorder. Structures of Nep1 revealed a dimer with a fold similar to the SPOUT-class of RNA-methyltransferases suggesting that Nep1 acts as a methyltransferase in ribosome biogenesis. The target for this putative methyltransferase activity has not been identified yet. We characterized the RNA-binding specificity of Methanocaldococcus jannaschii Nep1 by fluorescence- and NMR-spectroscopy as well as by yeast three-hybrid screening. Nep1 binds with high affinity to short RNA oligonucleotides corresponding to nt 910-921 of M. jannaschii 16S rRNA through a highly conserved basic surface cleft along the dimer interface. Nep1 only methylates RNAs containing a pseudouridine at a position corresponding to a previously identified hypermodified N1-methyl-N3-(3-amino-3-carboxypropyl) pseudouridine (m1acp3-Psi) in eukaryotic 18S rRNAs. Analysis of the methylated nucleoside by MALDI-mass spectrometry, HPLC and NMR shows that the methyl group is transferred to the N1 of the pseudouridine. Thus, Nep1 is the first identified example of an N1-specific pseudouridine methyltransferase. This enzymatic activity is also conserved in human Nep1 suggesting that Nep1 is the methyltransferase in the biosynthesis of m1acp3-Psi in eukaryotic 18S rRNAs.
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Affiliation(s)
- Jan Philip Wurm
- Institut für Molekulare Biowissenschaften, Johann-Wolfgang-Goethe-Universität, 60438 Frankfurt/M., Germany
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Luo Y, Li T, Yu F, Kramer T, Cristea IM. Resolving the composition of protein complexes using a MALDI LTQ Orbitrap. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:34-46. [PMID: 19822444 PMCID: PMC2820827 DOI: 10.1016/j.jasms.2009.08.026] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 08/18/2009] [Accepted: 08/31/2009] [Indexed: 05/28/2023]
Abstract
Current biological studies have been advanced by the continuous development of robust, accurate, and sensitive mass spectrometric technologies. The MALDI LTQ Orbitrap is a new addition to the Orbitrap configurations, known for their high resolving power and accuracy. This configuration provides features inherent to the MALDI source, such as reduced spectra complexity, forgiveness to contaminants, and sample retention for follow-up analyses with targeted or hypothesis-driven questions. Here we investigate its performance for characterizing the composition of isolated protein complexes. To facilitate the assessment, we selected two well characterized complexes from Saccharomyces cerevisiae, Apl1 and Nup84. Manual and automatic MS and MS/MS analyses readily resolved their compositions, with increased confidence of protein identification compared with our previous reports using MALDI QqTOF and MALDI IT. CID fragmentation of singly-charged peptides provided sufficient information for conclusive identification of the isolated proteins. We then assessed the resolution, accuracy, and sensitivity provided by this instrument in the context of analyzing the isolated protein assemblies. Our analysis of complex mixtures of singly-charged ions up to m/z 4000 showed that (1) the resolving power, inversely proportional to the square root of m/z, had over four orders of magnitude dynamic range; (2) internal calibration led to improved accuracy, with an average absolute mass error of 0.5 ppm and a distribution centered at 0 ppm; and (3) subfemtomole sensitivity was achieved using both CHCA and DHB matrices. Additionally, our analyses of a synthetic phosphorylated peptide in mixtures showed subfemtomole level of detection using neutral loss scanning.
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Affiliation(s)
| | | | | | | | - Ileana M. Cristea
- Address reprint requests to: 210 Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ 08544, Tel: 6092589417, Fax: 6092584575,
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Oberacher H. Frontiers of mass spectrometry in nucleic acids analysis. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2010; 16:351-365. [PMID: 20530841 DOI: 10.1255/ejms.1045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Nucleic acids research is a highly competitive field of research. A number of well established methods are available. The current output of high throughput ("next generation") sequencing technologies is impressive, and still technologies are continuing to make progress regarding read lengths, bp per second, accuracy and costs. Although in the 1990s MS was considered as an analytical platform for sequencing, it was soon realized that MS will never be competitive. Thus, the focus shifted from de novo sequencing towards other areas of application where MS has proven to be a powerful analytical tool. Potential niches for the application of MS in nucleic acids research include genotyping of genetic markers (single nucleotide polymorphisms, short tandem repeats, and combinations thereof), quality control of synthetic oligonucleotides, metabolic profiling of therapeutics, characterization of modified nucleobases in DNA and RNA molecules, and the study of non covalent interactions among nucleic acids as well as interactions of nucleic acids with drugs and proteins. The diversity of possible applications for MS highlights its significance for nucleic acid research.
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Affiliation(s)
- Herbert Oberacher
- Institute of Legal Medicine, Innsbruck Medical University, Innsbruck, Austria.
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