1
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Solotchi M, Patel SS. Proofreading mechanisms of the innate immune receptor RIG-I: distinguishing self and viral RNA. Biochem Soc Trans 2024; 52:1131-1148. [PMID: 38884803 DOI: 10.1042/bst20230724] [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: 04/13/2024] [Revised: 06/02/2024] [Accepted: 06/04/2024] [Indexed: 06/18/2024]
Abstract
The RIG-I-like receptors (RLRs), comprising retinoic acid-inducible gene I (RIG-I), melanoma differentiation-associated gene 5 (MDA5), and laboratory of genetics and physiology 2 (LGP2), are pattern recognition receptors belonging to the DExD/H-box RNA helicase family of proteins. RLRs detect viral RNAs in the cytoplasm and respond by initiating a robust antiviral response that up-regulates interferon and cytokine production. RIG-I and MDA5 complement each other by recognizing different RNA features, and LGP2 regulates their activation. RIG-I's multilayered RNA recognition and proofreading mechanisms ensure accurate viral RNA detection while averting harmful responses to host RNAs. RIG-I's C-terminal domain targets 5'-triphosphate double-stranded RNA (dsRNA) blunt ends, while an intrinsic gating mechanism prevents the helicase domains from non-specifically engaging with host RNAs. The ATPase and RNA translocation activity of RIG-I adds another layer of selectivity by minimizing the lifetime of RIG-I on non-specific RNAs, preventing off-target activation. The versatility of RIG-I's ATPase function also amplifies downstream signaling by enhancing the signaling domain (CARDs) exposure on 5'-triphosphate dsRNA and promoting oligomerization. In this review, we offer an in-depth understanding of the mechanisms RIG-I uses to facilitate viral RNA sensing and regulate downstream activation of the immune system.
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Affiliation(s)
- Mihai Solotchi
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, U.S.A
- Graduate School of Biomedical Sciences, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, U.S.A
| | - Smita S Patel
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, U.S.A
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2
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Weber F, Motzkus NA, Brandl L, Möhler M, Alempijevic A, Jäschke A. Identification and in vitro characterization of UDP-GlcNAc-RNA cap-modifying and decapping enzymes. Nucleic Acids Res 2024; 52:5438-5450. [PMID: 38716860 PMCID: PMC11162767 DOI: 10.1093/nar/gkae353] [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: 06/13/2023] [Revised: 04/09/2024] [Accepted: 04/22/2024] [Indexed: 06/11/2024] Open
Abstract
In recent years, several noncanonical RNA caps derived from cofactors and metabolites have been identified. Purine-containing RNA caps have been extensively studied, with multiple decapping enzymes identified and efficient capture and sequencing protocols developed for nicotinamide adenine dinucleotide (NAD)-RNA, which allowed for a stepwise elucidation of capping functions. Despite being identified as an abundant noncanonical RNA-cap, UDP-sugar-capped RNA remains poorly understood, which is partly due to its complex in vitro preparation. Here, we describe a scalable synthesis of sugar-capped uridine-guanosine dinucleotides from readily available protected building blocks and their enzymatic conversion into several cell wall precursor-capped dinucleotides. We employed these capped dinucleotides in T7 RNA polymerase-catalyzed in vitro transcription reactions to efficiently generate RNAs capped with uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), its N-azidoacetyl derivative UDP-GlcNAz, and various cell wall precursors. We furthermore identified four enzymes capable of processing UDP-GlcNAc-capped RNA in vitro: MurA, MurB and MurC from Escherichia coli can sequentially modify the sugar-cap structure and were used to introduce a bioorthogonal, clickable moiety, and the human Nudix hydrolase Nudt5 was shown to efficiently decap UDP-GlcNAc-RNA. Our findings underscore the importance of efficient synthetic methods for capped model RNAs. Additionally, we provide useful enzymatic tools that could be utilized in the development and application of UDP-GlcNAc capture and sequencing protocols. Such protocols are essential for deepening our understanding of the widespread yet enigmatic GlcNAc modification of RNA and its physiological significance.
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Affiliation(s)
- Frederik Weber
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, Heidelberg 69120, Germany
| | - Nikolas Alexander Motzkus
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, Heidelberg 69120, Germany
| | - Leona Brandl
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, Heidelberg 69120, Germany
| | - Marvin Möhler
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, Heidelberg 69120, Germany
| | - Andrijana Alempijevic
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, Heidelberg 69120, Germany
| | - Andres Jäschke
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, Heidelberg 69120, Germany
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3
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Chen S, Jiang Z, Li Q, Pan W, Chen Y, Liu J. Viral RNA capping: Mechanisms and antiviral therapy. J Med Virol 2024; 96:e29622. [PMID: 38682614 DOI: 10.1002/jmv.29622] [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: 12/19/2023] [Revised: 03/25/2024] [Accepted: 04/11/2024] [Indexed: 05/01/2024]
Abstract
RNA capping is an essential trigger for protein translation in eukaryotic cells. Many viruses have evolved various strategies for initiating the translation of viral genes and generating progeny virions in infected cells via synthesizing cap structure or stealing the RNA cap from nascent host messenger ribonucleotide acid (mRNA). In addition to protein translation, a new understanding of the role of the RNA cap in antiviral innate immunity has advanced the field of mRNA synthesis in vitro and therapeutic applications. Recent studies on these viral RNA capping systems have revealed startlingly diverse ways and molecular machinery. A comprehensive understanding of how viruses accomplish the RNA capping in infected cells is pivotal for designing effective broad-spectrum antiviral therapies. Here we systematically review the contemporary insights into the RNA-capping mechanisms employed by viruses causing human and animal infectious diseases, while also highlighting its impact on host antiviral innate immune response. The therapeutic applications of targeting RNA capping against viral infections and the development of RNA-capping inhibitors are also summarized.
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Affiliation(s)
- Saini Chen
- National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Zhimin Jiang
- National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Qiuchen Li
- National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Wenliang Pan
- National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yu Chen
- National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jinhua Liu
- National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
- Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, College of Veterinary Medicine, China Agricultural University, Beijing, China
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4
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Zhou KI, Pecot CV, Holley CL. 2'- O-methylation (Nm) in RNA: progress, challenges, and future directions. RNA (NEW YORK, N.Y.) 2024; 30:570-582. [PMID: 38531653 PMCID: PMC11019748 DOI: 10.1261/rna.079970.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 02/09/2024] [Indexed: 03/28/2024]
Abstract
RNA 2'-O-methylation (Nm) is highly abundant in noncoding RNAs including ribosomal RNA (rRNA), transfer RNA (tRNA), and small nuclear RNA (snRNA), and occurs in the 5' cap of virtually all messenger RNAs (mRNAs) in higher eukaryotes. More recently, Nm has also been reported to occur at internal sites in mRNA. High-throughput methods have been developed for the transcriptome-wide detection of Nm. However, these methods have mostly been applied to abundant RNAs such as rRNA, and the validity of the internal mRNA Nm sites detected with these approaches remains controversial. Nonetheless, Nm in both coding and noncoding RNAs has been demonstrated to impact cellular processes, including translation and splicing. In addition, Nm modifications at the 5' cap and possibly at internal sites in mRNA serve to prevent the binding of nucleic acid sensors, thus preventing the activation of the innate immune response by self-mRNAs. Finally, Nm has been implicated in a variety of diseases including cancer, cardiovascular diseases, and neurologic syndromes. In this review, we discuss current challenges in determining the distribution, regulation, function, and disease relevance of Nm, as well as potential future directions for the field.
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Affiliation(s)
- Katherine I Zhou
- Division of Medical Oncology, Department of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Chad V Pecot
- UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Division of Hematology and Oncology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514, USA
- University of North Carolina RNA Discovery Center, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Christopher L Holley
- Division of Cardiology, Department of Medicine, Duke University, Durham, North Carolina 27710, USA
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5
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Chen BJ, Lin CH, Wu HY, Cai JJ, Chao DY. Experimental and analytical pipeline for sub-genomic RNA landscape of coronavirus by Nanopore sequencer. Microbiol Spectr 2024; 12:e0395423. [PMID: 38483513 PMCID: PMC10986531 DOI: 10.1128/spectrum.03954-23] [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: 11/15/2023] [Accepted: 02/26/2024] [Indexed: 04/06/2024] Open
Abstract
Coronaviruses (CoVs), including severe acute respiratory syndrome coronavirus 2, can infect a variety of mammalian and avian hosts with significant medical and economic consequences. During the life cycle of CoV, a coordinated series of subgenomic RNAs, including canonical subgenomic messenger RNA and non-canonical defective viral genomes (DVGs), are generated with different biological implications. Studies that adopted the Nanopore sequencer (ONT) to investigate the landscape and dynamics of viral RNA subgenomic transcriptomes applied arbitrary bioinformatics parameters without justification or experimental validation. The current study used bovine coronavirus (BCoV), which can be performed under biosafety level 2 for library construction and experimental validation using traditional colony polymerase chain reaction and Sanger sequencing. Four different ONT protocols, including RNA direct and cDNA direct sequencing with or without exonuclease treatment, were used to generate RNA transcriptomic libraries from BCoV-infected cell lysates. Through rigorously examining the k-mer, gap size, segment size, and bin size, the optimal cutoffs for the bioinformatic pipeline were determined to remove the sequence noise while keeping the informative DVG reads. The sensitivity and specificity of identifying DVG reads using the proposed pipeline can reach 82.6% and 99.6% under the k-mer size cutoff of 15. Exonuclease treatment reduced the abundance of RNA transcripts; however, it was not necessary for future library preparation. Additional recovery of clipped BCoV nucleotide sequences with experimental validation expands the landscape of the CoV discontinuous RNA transcriptome, whose biological function requires future investigation. The results of this study provide the benchmarks for library construction and bioinformatic parameters for studying the discontinuous CoV RNA transcriptome.IMPORTANCEFunctional defective viral genomic RNA, containing all the cis-acting elements required for translation or replication, may play different roles in triggering cell innate immune signaling, interfering with the canonical subgenomic messenger RNA transcription/translation or assisting in establishing persistence infection. This study does not only provide benchmarks for library construction and bioinformatic parameters for studying the discontinuous coronavirus RNA transcriptome but also reveals the complexity of the bovine coronavirus transcriptome, whose functional assays will be critical in future studies.
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Affiliation(s)
- Bo-Jia Chen
- Doctoral Program in Microbial Genomics, National Chung Hsing University and Academia Sinica, Taichung, Taiwan
| | - Ching-Hung Lin
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Hung-Yi Wu
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - James J. Cai
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Day-Yu Chao
- Doctoral Program in Microbial Genomics, National Chung Hsing University and Academia Sinica, Taichung, Taiwan
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
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6
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Qiu J, Xu X, Guo J, Wang Z, Wu J, Ding H, Xu Y, Wu Y, Ying Q, Qiu J, Wu S, Shi S. Comparison of extraction processes, characterization and intestinal protection activity of Bletilla striata polysaccharides. Int J Biol Macromol 2024; 263:130267. [PMID: 38378109 DOI: 10.1016/j.ijbiomac.2024.130267] [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: 08/14/2023] [Revised: 02/12/2024] [Accepted: 02/15/2024] [Indexed: 02/22/2024]
Abstract
We optimized the extraction process of Bletilla striata polysaccharides using orthogonal design, Box-Behnken design (BBD), and genetic algorithm-back propagation (GA-BP), then compared and evaluated them to confirm that the combination of BBD and GA-BP neural networks was capable of increasing polysaccharide yields and antioxidant activity. The optimal extraction parameters were as follows: liquid-to-solid ratio of 15 mL/g, extraction power of 450 W, and extraction time of 34 min. Under these conditions, the polysaccharide yield and antioxidant activity were 8.29 ± 0.50 % and 26.20 ± 0.28 (mM FE/mg). Subsequently, the polysaccharide was purified to obtain purified Bletilla striata polysaccharides 1 (pBSP1) with a Mw of 255.172 kDa. Scanning electron microscope (SEM), ultraviolet-visible detector (UV), fourier transform infrared spectrometer (FTIR), high performance liquid chromatography (HPLC), X-ray diffraction (XRD), nuclear magnetic resonance (NMR) and periodate oxidation were used to analyze the structure of pBSP1. The results showed pBSP1 had a smooth surface and a rough interior, with a composition of α-D conformation glucose (18.23 %) and β-D conformation mannose (53.77 %), and an amorphous crystal structure. According to the results of thermogravimetric and rheological tests, pBSP1 exhibits good thermal stability and viscoelastic behavior. Furthermore, pBSP1 protected lipopolysaccharide (LPS)-induced GES - 1 and Caco2 cells, the results showed pBSP1(400 μg/mL) lowered TEER synthesis in Caco2 cells as well as apoptosis and reactive oxygen species (ROS) production in both cells, indicating that pBSP1 may have an intestine protective effect.
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Affiliation(s)
- Junjie Qiu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Xiao Xu
- Asset Management Co., Ltd, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Jingyan Guo
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Zhenyu Wang
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Jinjin Wu
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Huiqin Ding
- The Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yuchen Xu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Yili Wu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Qianyi Ying
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Jiawei Qiu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Suxiang Wu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China.
| | - Senlin Shi
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China.
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7
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Liu WW, Zheng SQ, Li T, Fei YF, Wang C, Zhang S, Wang F, Jiang GM, Wang H. RNA modifications in cellular metabolism: implications for metabolism-targeted therapy and immunotherapy. Signal Transduct Target Ther 2024; 9:70. [PMID: 38531882 DOI: 10.1038/s41392-024-01777-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 02/08/2024] [Accepted: 02/19/2024] [Indexed: 03/28/2024] Open
Abstract
Cellular metabolism is an intricate network satisfying bioenergetic and biosynthesis requirements of cells. Relevant studies have been constantly making inroads in our understanding of pathophysiology, and inspiring development of therapeutics. As a crucial component of epigenetics at post-transcription level, RNA modification significantly determines RNA fates, further affecting various biological processes and cellular phenotypes. To be noted, immunometabolism defines the metabolic alterations occur on immune cells in different stages and immunological contexts. In this review, we characterize the distribution features, modifying mechanisms and biological functions of 8 RNA modifications, including N6-methyladenosine (m6A), N6,2'-O-dimethyladenosine (m6Am), N1-methyladenosine (m1A), 5-methylcytosine (m5C), N4-acetylcytosine (ac4C), N7-methylguanosine (m7G), Pseudouridine (Ψ), adenosine-to-inosine (A-to-I) editing, which are relatively the most studied types. Then regulatory roles of these RNA modification on metabolism in diverse health and disease contexts are comprehensively described, categorized as glucose, lipid, amino acid, and mitochondrial metabolism. And we highlight the regulation of RNA modifications on immunometabolism, further influencing immune responses. Above all, we provide a thorough discussion about clinical implications of RNA modification in metabolism-targeted therapy and immunotherapy, progression of RNA modification-targeted agents, and its potential in RNA-targeted therapeutics. Eventually, we give legitimate perspectives for future researches in this field from methodological requirements, mechanistic insights, to therapeutic applications.
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Affiliation(s)
- Wei-Wei Liu
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- School of Clinical Medicine, Shandong University, Jinan, China
| | - Si-Qing Zheng
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Core Unit of National Clinical Research Center for Laboratory Medicine, Hefei, China
| | - Tian Li
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Core Unit of National Clinical Research Center for Laboratory Medicine, Hefei, China
| | - Yun-Fei Fei
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Core Unit of National Clinical Research Center for Laboratory Medicine, Hefei, China
| | - Chen Wang
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Core Unit of National Clinical Research Center for Laboratory Medicine, Hefei, China
| | - Shuang Zhang
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Core Unit of National Clinical Research Center for Laboratory Medicine, Hefei, China
| | - Fei Wang
- Neurosurgical Department, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
| | - Guan-Min Jiang
- Department of Clinical Laboratory, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.
| | - Hao Wang
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
- Core Unit of National Clinical Research Center for Laboratory Medicine, Hefei, China.
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8
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Warminski M, Trepkowska E, Smietanski M, Sikorski PJ, Baranowski MR, Bednarczyk M, Kedzierska H, Majewski B, Mamot A, Papiernik D, Popielec A, Serwa RA, Shimanski BA, Sklepkiewicz P, Sklucka M, Sokolowska O, Spiewla T, Toczydlowska-Socha D, Warminska Z, Wolosewicz K, Zuberek J, Mugridge JS, Nowis D, Golab J, Jemielity J, Kowalska J. Trinucleotide mRNA Cap Analogue N6-Benzylated at the Site of Posttranscriptional m6A m Mark Facilitates mRNA Purification and Confers Superior Translational Properties In Vitro and In Vivo. J Am Chem Soc 2024; 146:8149-8163. [PMID: 38442005 PMCID: PMC10979456 DOI: 10.1021/jacs.3c12629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 02/12/2024] [Accepted: 02/12/2024] [Indexed: 03/07/2024]
Abstract
Eukaryotic mRNAs undergo cotranscriptional 5'-end modification with a 7-methylguanosine cap. In higher eukaryotes, the cap carries additional methylations, such as m6Am─a common epitranscriptomic mark unique to the mRNA 5'-end. This modification is regulated by the Pcif1 methyltransferase and the FTO demethylase, but its biological function is still unknown. Here, we designed and synthesized a trinucleotide FTO-resistant N6-benzyl analogue of the m6Am-cap-m7GpppBn6AmpG (termed AvantCap) and incorporated it into mRNA using T7 polymerase. mRNAs carrying Bn6Am showed several advantages over typical capped transcripts. The Bn6Am moiety was shown to act as a reversed-phase high-performance liquid chromatography (RP-HPLC) purification handle, allowing the separation of capped and uncapped RNA species, and to produce transcripts with lower dsRNA content than reference caps. In some cultured cells, Bn6Am mRNAs provided higher protein yields than mRNAs carrying Am or m6Am, although the effect was cell-line-dependent. m7GpppBn6AmpG-capped mRNAs encoding reporter proteins administered intravenously to mice provided up to 6-fold higher protein outputs than reference mRNAs, while mRNAs encoding tumor antigens showed superior activity in therapeutic settings as anticancer vaccines. The biochemical characterization suggests several phenomena potentially underlying the biological properties of AvantCap: (i) reduced propensity for unspecific interactions, (ii) involvement in alternative translation initiation, and (iii) subtle differences in mRNA impurity profiles or a combination of these effects. AvantCapped-mRNAs bearing the Bn6Am may pave the way for more potent mRNA-based vaccines and therapeutics and serve as molecular tools to unravel the role of m6Am in mRNA.
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Affiliation(s)
- Marcin Warminski
- Division
of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-089 Warsaw, Poland
| | - Edyta Trepkowska
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | | | - Pawel J. Sikorski
- Centre
of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
- Laboratory
of Epitranscriptomics, Department of Environmental Microbiology and
Biotechnology, Institute of Microbiology, Faculty of Biology, Biological
and Chemical Research Centre, University
of Warsaw, 02-089 Warsaw, Poland
| | | | - Marcelina Bednarczyk
- Centre
of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Hanna Kedzierska
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Bartosz Majewski
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Adam Mamot
- Centre
of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
| | - Diana Papiernik
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Agnieszka Popielec
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Remigiusz A. Serwa
- Proteomics
Core Facility, IMol Polish Academy of Sciences, 02-247 Warsaw, Poland
| | - Brittany A. Shimanski
- Department
of Chemistry & Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Piotr Sklepkiewicz
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Marta Sklucka
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Olga Sokolowska
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Tomasz Spiewla
- Division
of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-089 Warsaw, Poland
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | | | - Zofia Warminska
- Centre
of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
| | - Karol Wolosewicz
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Joanna Zuberek
- Division
of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-089 Warsaw, Poland
| | - Jeffrey S. Mugridge
- Department
of Chemistry & Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Dominika Nowis
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
- Laboratory
of Experimental Medicine, Faculty of Medicine, Medical University of Warsaw, 02-097 Warsaw, Poland
| | - Jakub Golab
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
- Laboratory
of Experimental Medicine, Faculty of Medicine, Medical University of Warsaw, 02-097 Warsaw, Poland
| | - Jacek Jemielity
- Centre
of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Joanna Kowalska
- Division
of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-089 Warsaw, Poland
- Explorna
Therapeutics sp. z o.o. Zwirki i Wigury 93, 02-089 Warsaw, Poland
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9
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Avila-Bonilla RG, Macias S. The molecular language of RNA 5' ends: guardians of RNA identity and immunity. RNA (NEW YORK, N.Y.) 2024; 30:327-336. [PMID: 38325897 PMCID: PMC10946433 DOI: 10.1261/rna.079942.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 02/01/2024] [Indexed: 02/09/2024]
Abstract
RNA caps are deposited at the 5' end of RNA polymerase II transcripts. This modification regulates several steps of gene expression, in addition to marking transcripts as self to enable the innate immune system to distinguish them from uncapped foreign RNAs, including those derived from viruses. Specialized immune sensors, such as RIG-I and IFITs, trigger antiviral responses upon recognition of uncapped cytoplasmic transcripts. Interestingly, uncapped transcripts can also be produced by mammalian hosts. For instance, 5'-triphosphate RNAs are generated by RNA polymerase III transcription, including tRNAs, Alu RNAs, or vault RNAs. These RNAs have emerged as key players of innate immunity, as they can be recognized by the antiviral sensors. Mechanisms that regulate the presence of 5'-triphosphates, such as 5'-end dephosphorylation or RNA editing, prevent immune recognition of endogenous RNAs and excessive inflammation. Here, we provide a comprehensive overview of the complexity of RNA cap structures and 5'-triphosphate RNAs, highlighting their roles in transcript identity, immune surveillance, and disease.
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Affiliation(s)
- Rodolfo Gamaliel Avila-Bonilla
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, EH9 3FL Edinburgh, United Kingdom
| | - Sara Macias
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, EH9 3FL Edinburgh, United Kingdom
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10
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Wang X, Yu D, Yu J, Hu H, Hang R, Amador Z, Chen Q, Chai J, Chen X. Toll/interleukin-1 receptor (TIR) domain-containing proteins have NAD-RNA decapping activity. Nat Commun 2024; 15:2261. [PMID: 38480720 PMCID: PMC10937652 DOI: 10.1038/s41467-024-46499-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 02/29/2024] [Indexed: 03/17/2024] Open
Abstract
The occurrence of NAD+ as a non-canonical RNA cap has been demonstrated in diverse organisms. TIR domain-containing proteins present in all kingdoms of life act in defense responses and can have NADase activity that hydrolyzes NAD+. Here, we show that TIR domain-containing proteins from several bacterial and one archaeal species can remove the NAM moiety from NAD-capped RNAs (NAD-RNAs). We demonstrate that the deNAMing activity of AbTir (from Acinetobacter baumannii) on NAD-RNA specifically produces a cyclic ADPR-RNA, which can be further decapped in vitro by known decapping enzymes. Heterologous expression of the wild-type but not a catalytic mutant AbTir in E. coli suppressed cell propagation and reduced the levels of NAD-RNAs from a subset of genes before cellular NAD+ levels are impacted. Collectively, the in vitro and in vivo analyses demonstrate that TIR domain-containing proteins can function as a deNAMing enzyme of NAD-RNAs, raising the possibility of TIR domain proteins acting in gene expression regulation.
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Affiliation(s)
- Xufeng Wang
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Joint Center for Life Sciences, School of Life Sciences, Peking University, Beijing, 100871, China
- Beijing Advanced Center of RNA Biology (BEACON), Peking University, Beijing, 100871, China
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Dongli Yu
- Institute of Biochemistry, University of Cologne, Cologne, 50674, Germany
- Max Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02215, USA
| | - Jiancheng Yu
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT, 84112, USA
| | - Hao Hu
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Joint Center for Life Sciences, School of Life Sciences, Peking University, Beijing, 100871, China
- Beijing Advanced Center of RNA Biology (BEACON), Peking University, Beijing, 100871, China
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Runlai Hang
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Joint Center for Life Sciences, School of Life Sciences, Peking University, Beijing, 100871, China
- Beijing Advanced Center of RNA Biology (BEACON), Peking University, Beijing, 100871, China
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Zachary Amador
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Qi Chen
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT, 84112, USA
- Molecular Medicine Program, Division of Urology, Department of Surgery, University of Utah School of Medicine, Salt Lake City, UT, 84112, USA
| | - Jijie Chai
- Institute of Biochemistry, University of Cologne, Cologne, 50674, Germany
- Max Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
| | - Xuemei Chen
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Joint Center for Life Sciences, School of Life Sciences, Peking University, Beijing, 100871, China.
- Beijing Advanced Center of RNA Biology (BEACON), Peking University, Beijing, 100871, China.
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11
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Ge S, Wang X, Wang Y, Dong M, Li D, Niu K, Wang T, Liu R, Zhao C, Liu N, Zhong M. Hidden features of NAD-RNA epitranscriptome in Drosophila life cycle. iScience 2024; 27:108618. [PMID: 38197055 PMCID: PMC10775904 DOI: 10.1016/j.isci.2023.108618] [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: 04/26/2023] [Revised: 09/26/2023] [Accepted: 11/30/2023] [Indexed: 01/11/2024] Open
Abstract
Nicotinamide adenine dinucleotide (NAD), a nucleotide-containing metabolite, can be incorporated into the RNA 5'-terminus to result in NAD-capped RNA (NAD-RNA). Since NAD has been heightened as one of the most essential metabolites in cells, its linkage to RNA represents a critical but poorly studied modification at the epitranscriptomic level. Here, we design a highly sensitive method, DO-seq, to capture NAD-RNAs. Using Drosophila, we identify thousands of previously unexplored NAD-RNAs and their dynamics in the fly life cycle, from embryo to adult. We show the evidence that chromosomal clustering might be the structural basis by which co-expression can couple with NAD capping on physically and functionally linked genes. Furthermore, we note that NAD capping of cuticle genes inversely correlates with their gene expression. Combined, we propose NAD-RNA epitranscriptome as a hidden layer of regulation that underlies biological processes. DO-seq empowers the identification of NAD-capped RNAs, facilitating functional investigation into this modification.
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Affiliation(s)
- Shuwen Ge
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Road, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xueting Wang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Road, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yingqin Wang
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Lung Inflammation and Injury, 180 Fenglin Road, Shanghai, China
- Shanghai Institute of Infectious Disease and Biosecurity, School of Public Health, Fudan University, Shanghai, China
| | - Minghui Dong
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Lung Inflammation and Injury, 180 Fenglin Road, Shanghai, China
- Shanghai Institute of Infectious Disease and Biosecurity, School of Public Health, Fudan University, Shanghai, China
| | - Dean Li
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Road, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kongyan Niu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Road, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tongyao Wang
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, 131 Dong An Road, Shanghai 200032, China
| | - Rui Liu
- Singlera Genomics, 500 Fu Rong Hua Road, Shanghai 201204, China
| | - Chao Zhao
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, 131 Dong An Road, Shanghai 200032, China
| | - Nan Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Road, Shanghai 201210, China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, 131 Dong An Road, Shanghai 200032, China
- Shanghai Key Laboratory of Aging Studies, 100 Hai Ke Road, Shanghai 201210, China
| | - Ming Zhong
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Lung Inflammation and Injury, 180 Fenglin Road, Shanghai, China
- Shanghai Institute of Infectious Disease and Biosecurity, School of Public Health, Fudan University, Shanghai, China
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12
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Potužník JF, Cahova H. If the 5' cap fits (wear it) - Non-canonical RNA capping. RNA Biol 2024; 21:1-13. [PMID: 39007883 PMCID: PMC11253889 DOI: 10.1080/15476286.2024.2372138] [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: 04/10/2024] [Accepted: 06/18/2024] [Indexed: 07/16/2024] Open
Abstract
RNA capping is a prominent RNA modification that influences RNA stability, metabolism, and function. While it was long limited to the study of the most abundant eukaryotic canonical m7G cap, the field recently went through a large paradigm shift with the discovery of non-canonical RNA capping in bacteria and ultimately all domains of life. The repertoire of non-canonical caps has expanded to encompass metabolite caps, including NAD, FAD, CoA, UDP-Glucose, and ADP-ribose, alongside alarmone dinucleoside polyphosphate caps, and methylated phosphate cap-like structures. This review offers an introduction into the field, presenting a summary of the current knowledge about non-canonical RNA caps. We highlight the often still enigmatic biological roles of the caps together with their processing enzymes, focusing on the most recent discoveries. Furthermore, we present the methods used for the detection and analysis of these non-canonical RNA caps and thus provide an introduction into this dynamic new field.
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Affiliation(s)
- Jiří František Potužník
- Institute of Organic Chemistry and Biochemistry of the CAS, Prague 6, Czechia
- Department of Cell Biology, Charles University, Faculty of Science, Prague 2, Czechia
| | - Hana Cahova
- Institute of Organic Chemistry and Biochemistry of the CAS, Prague 6, Czechia
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13
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Benak D, Kolar F, Zhang L, Devaux Y, Hlavackova M. RNA modification m 6Am: the role in cardiac biology. Epigenetics 2023; 18:2218771. [PMID: 37331009 DOI: 10.1080/15592294.2023.2218771] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 05/19/2023] [Accepted: 05/23/2023] [Indexed: 06/20/2023] Open
Abstract
Epitranscriptomic modifications have recently emerged into the spotlight of researchers due to their vast regulatory effects on gene expression and thereby cellular physiology and pathophysiology. N6,2'-O-dimethyladenosine (m6Am) is one of the most prevalent chemical marks on RNA and is dynamically regulated by writers (PCIF1, METTL4) and erasers (FTO). The presence or absence of m6Am in RNA affects mRNA stability, regulates transcription, and modulates pre-mRNA splicing. Nevertheless, its functions in the heart are poorly known. This review summarizes the current knowledge and gaps about m6Am modification and its regulators in cardiac biology. It also points out technical challenges and lists the currently available techniques to measure m6Am. A better understanding of epitranscriptomic modifications is needed to improve our knowledge of the molecular regulations in the heart which may lead to novel cardioprotective strategies.
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Affiliation(s)
- Daniel Benak
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Frantisek Kolar
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Lu Zhang
- Bioinformatics Platform, Luxembourg Institute of Health, Strassen, Luxembourg
| | - Yvan Devaux
- Cardiovascular Research Unit, Department of Population Health, Luxembourg Institute of Health, Strassen, Luxembourg
| | - Marketa Hlavackova
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
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14
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Ammann G, Berg M, Dalwigk JF, Kaiser SM. Pitfalls in RNA Modification Quantification Using Nucleoside Mass Spectrometry. Acc Chem Res 2023; 56:3121-3131. [PMID: 37944919 PMCID: PMC10666278 DOI: 10.1021/acs.accounts.3c00402] [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: 07/18/2023] [Revised: 10/10/2023] [Accepted: 10/10/2023] [Indexed: 11/12/2023]
Abstract
In recent years, there has been a high interest in researching RNA modifications, as they are involved in many cellular processes and in human diseases. A substantial set of enzymes within the cell, called RNA writers, place RNA modifications selectively and site-specifically. Another set of enzymes, called readers, recognize these modifications which guide the fate of the modified RNA. Although RNA is a transient molecule and RNA modification could be removed by RNA degradation, a subclass of enzymes, called RNA erasers, remove RNA modifications selectively and site-specifically to alter the characteristics of the RNA. The detection of RNA modifications can be done by various methods including second and next generation sequencing but also mass spectrometry. An approach capable of both qualitative and quantitative RNA modification analysis is liquid chromatography coupled to mass spectrometry of enzymatic hydrolysates of RNA into nucleosides. However, for successful detection and quantification, various factors must be considered to avoid biased identification and inaccurate quantification. In this Account, we identify three classes of errors that may distort the analysis. These classes comprise (I) errors related to chemical instabilities, (II) errors revolving around enzymatic hydrolysis to nucleosides, and (III) errors arising from issues with chromatographic separation and/or subsequent mass spectrometric analysis.A prominent example for class 1 is Dimroth rearrangement of m1A to m6A, but class 1 also comprises hydrolytic reactions and reactions with buffer components. Here, we also present the conversion of m3C to m3U under mild alkaline conditions and propose a practical solution to overcome these instabilities. Class 2 errors-such as contaminations in hydrolysis reagents or nuclease specificities-have led to erroneous discoveries of nucleosides in the past and possess the potential for misquantification of nucleosides. Impurities in the samples may also lead to class 3 errors: For instance, issues with chromatographic separation may arise from residual organic solvents, and salt adducts may hamper mass spectrometric quantification. This Account aims to highlight various errors connected to mass spectrometry analysis of nucleosides and presents solutions for how to overcome or circumnavigate those issues. Therefore, the authors anticipate that many scientists, but especially those who plan on doing nucleoside mass spectrometry, will benefit from the collection of data presented in this Account as a raised awareness, toward the variety of potential pitfalls, may further enhance the quality of data.
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Affiliation(s)
- Gregor Ammann
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany
| | - Maximilian Berg
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany
| | - Jan Felix Dalwigk
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany
| | - Stefanie M. Kaiser
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany
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15
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Möhler M, Jäschke A. Future Perspectives for the Identification and Sequencing of Nicotinamide Adenine Dinucleotide-Capped RNAs. Acc Chem Res 2023; 56:3000-3009. [PMID: 37852615 PMCID: PMC10634297 DOI: 10.1021/acs.accounts.3c00446] [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: 07/31/2023] [Indexed: 10/20/2023]
Abstract
Ribonucleic acid (RNA) is composed primarily of four canonical building blocks. In addition, more than 170 modifications contribute to its stability and function. Metabolites like nicotinamide adenine dinucleotide (NAD) were found to function as 5'-cap structures of RNA, just like 7-methylguanosine (m7G). The identification of NAD-capped RNA sequences was first made possible by NAD captureSeq, a multistep protocol for the specific targeting, purification, and sequencing of NAD-capped RNAs, developed in the authors' laboratory in the year 2015. In recent years, a number of NAD-RNA identification protocols have been developed by researchers around the world. They have enabled the discovery and identification of NAD-RNAs in bacteria, archaea, yeast, plants, mice, and human cells, and they play a key role in studying the biological functions of NAD capping. We introduce the four parameters of yield, specificity, evaluability, and throughput and describe to the reader how an ideal NAD-RNA identification protocol would perform in each of these disciplines. These parameters are further used to describe and analyze existing protocols that follow two general methodologies: the capture approach and the decapping approach. Capture protocols introduce an exogenous moiety into the NAD-cap structure in order to either specifically purify or sequence NAD-capped RNAs. In decapping protocols, the NAD cap is digested to 5'-monophosphate RNA, which is then specifically targeted and sequenced. Both approaches, as well as the different protocols within them, have advantages and challenges that we evaluate based on the aforementioned parameters. In addition, we suggest improvements in order to meet the future needs of research on NAD-modified RNAs, which is beginning to emerge in the area of cell-type specific samples. A limiting factor of the capture approach is the need for large amounts of input RNA. Here we see a high potential for innovation within the key targeting step: The enzymatic modification reaction of the NAD-cap structure catalyzed by ADP-ribosyl cyclase (ADPRC) is a major contributor to the parameters of yield and specificity but has mostly seen minor changes since the pioneering protocol of NAD captureSeq and needs to be more stringently analyzed. The major challenge of the decapping approach remains the specificity of the decapping enzymes, many of which act on a variety of 5'-cap structures. Exploration of new decapping enzymes or engineering of already known enzymes could lead to improvements in NAD-specific protocols. The use of a curated set of decapping enzymes in a combinatorial approach could allow for the simultaneous detection of multiple 5'-caps. The throughput of both approaches could be greatly improved by early sample pooling. We propose that this could be achieved by introducing a barcode RNA sequence before or immediately after the NAD-RNA targeting steps. With increased processing capacity and a potential decrease in the cost per sample, protocols will gain the potential to analyze large numbers of samples from different growth conditions and treatments. This will support the search for biological roles of NAD-capped RNAs in all types of organisms.
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Affiliation(s)
- Marvin Möhler
- Institute of Pharmacy and
Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
| | - Andres Jäschke
- Institute of Pharmacy and
Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
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16
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Chan C, Kwan Sze NS, Suzuki Y, Ohira T, Suzuki T, Begley TJ, Dedon PC. Dengue virus exploits the host tRNA epitranscriptome to promote viral replication. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.05.565734. [PMID: 37986976 PMCID: PMC10659268 DOI: 10.1101/2023.11.05.565734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
The 40-50 RNA modifications of the epitranscriptome regulate posttranscriptional gene expression. Here we show that flaviviruses hijack the host tRNA epitranscriptome to promote expression of pro-viral proteins, with tRNA-modifying ALKBH1 acting as a host restriction factor in dengue virus infection. Early in the infection of human Huh-7 cells, ALKBH1 and its tRNA products 5-formylcytidine (f5C) and 2'-O-methyl-5-formylcytidine (f5Cm) were reduced. ALKBH1 knockdown mimicked viral infection, but caused increased viral NS3 protein levels during infection, while ALKBH1 overexpression reduced NS3 levels and viral replication, and increased f5C and f5Cm. Viral NS5, but not host FTSJ1, increased f5Cm levels late in infection. Consistent with reports of impaired decoding of leucine UUA codon by f5Cm-modified tRNALeu(CAA), ALKBH1 knockdown induced translation of UUA-deficient transcripts, most having pro-viral functions. Our findings support a dynamic ALKBH1/f5Cm axis during dengue infection, with virally-induced remodeling of the proteome by tRNA reprogramming and codon-biased translation.
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Affiliation(s)
- Cheryl Chan
- Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, 138602, Singapore
| | - Newman Siu Kwan Sze
- School of Biological Sciences, Nanyang Technological University, Singapore 639798, Singapore
| | - Yuka Suzuki
- Department of Bioengineering, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takayuki Ohira
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Tsutomu Suzuki
- Department of Bioengineering, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Thomas J. Begley
- Department of Biological Sciences and The RNA Institute, College of Arts and Science, University at Albany, SUNY, Albany, NY, 12222, USA
| | - Peter C. Dedon
- Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, 138602, Singapore
- Department of Biological Engineering and Center for Environmental Health Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
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17
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Chan SH, Molé CN, Nye D, Mitchell L, Dai N, Buss J, Kneller DW, Whipple JM, Robb GB. Biochemical characterization of mRNA capping enzyme from Faustovirus. RNA (NEW YORK, N.Y.) 2023; 29:1803-1817. [PMID: 37625853 PMCID: PMC10578482 DOI: 10.1261/rna.079738.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023]
Abstract
The mammalian mRNA 5' cap structures play important roles in cellular processes such as nuclear export, efficient translation, and evading cellular innate immune surveillance and regulating 5'-mediated mRNA turnover. Hence, installation of the proper 5' cap is crucial in therapeutic applications of synthetic mRNA. The core 5' cap structure, Cap-0, is generated by three sequential enzymatic activities: RNA 5' triphosphatase, RNA guanylyltransferase, and cap N7-guanine methyltransferase. Vaccinia virus RNA capping enzyme (VCE) is a heterodimeric enzyme that has been widely used in synthetic mRNA research and manufacturing. The large subunit of VCE D1R exhibits a modular structure where each of the three structural domains possesses one of the three enzyme activities, whereas the small subunit D12L is required to activate the N7-guanine methyltransferase activity. Here, we report the characterization of a single-subunit RNA capping enzyme from an amoeba giant virus. Faustovirus RNA capping enzyme (FCE) exhibits a modular array of catalytic domains in common with VCE and is highly efficient in generating the Cap-0 structure without an activation subunit. Phylogenetic analysis suggests that FCE and VCE are descended from a common ancestral capping enzyme. We found that compared to VCE, FCE exhibits higher specific activity, higher activity toward RNA containing secondary structures and a free 5' end, and a broader temperature range, properties favorable for synthetic mRNA manufacturing workflows.
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Affiliation(s)
- S Hong Chan
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Christa N Molé
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Dillon Nye
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Lili Mitchell
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Nan Dai
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Jackson Buss
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | | | | | - G Brett Robb
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
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18
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Burdick JT, Comai A, Bruzel A, Sun G, Dedon PC, Cheung VG. Nanopore-based direct sequencing of RNA transcripts with 10 different modified nucleotides reveals gaps in existing technology. G3 (BETHESDA, MD.) 2023; 13:jkad200. [PMID: 37655917 PMCID: PMC10627276 DOI: 10.1093/g3journal/jkad200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 06/14/2023] [Accepted: 08/23/2023] [Indexed: 09/02/2023]
Abstract
RNA undergoes complex posttranscriptional processing including chemical modifications of the nucleotides. The resultant-modified nucleotides are an integral part of RNA sequences that must be considered in studying the biology of RNA and in the design of RNA therapeutics. However, the current "RNA-sequencing" methods primarily sequence complementary DNA rather than RNA itself, which means that the modifications present in RNA are not captured in the sequencing results. Emerging direct RNA-sequencing technologies, such as those offered by Oxford Nanopore, aim to address this limitation. In this study, we synthesized and used Nanopore technology to sequence RNA transcripts consisting of canonical nucleotides and 10 different modifications in various concentrations. The results show that direct RNA sequencing still has a baseline error rate of >10%, and although some modifications can be detected, many remain unidentified. Thus, there is a need to develop sequencing technologies and analysis methods that can comprehensively capture the total complexity of RNA. The RNA sequences obtained through this project are made available for benchmarking analysis methods.
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Affiliation(s)
- Joshua T Burdick
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Annelise Comai
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alan Bruzel
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Guangxin Sun
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Peter C Dedon
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Vivian G Cheung
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109, USA
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19
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Mickutė M, Krasauskas R, Kvederavičiūtė K, Tupikaitė G, Osipenko A, Kaupinis A, Jazdauskaitė M, Mineikaitė R, Valius M, Masevičius V, Vilkaitis G. Interplay between bacterial 5'-NAD-RNA decapping hydrolase NudC and DEAD-box RNA helicase CsdA in stress responses. mSystems 2023; 8:e0071823. [PMID: 37706681 PMCID: PMC10654059 DOI: 10.1128/msystems.00718-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 09/15/2023] Open
Abstract
IMPORTANCE Non-canonical 5'-caps removing RNA hydrolase NudC, along with stress-responsive RNA helicase CsdA, is crucial for 5'-NAD-RNA decapping and bacterial movement.
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Affiliation(s)
- Milda Mickutė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Renatas Krasauskas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Kotryna Kvederavičiūtė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Gytė Tupikaitė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Aleksandr Osipenko
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Algirdas Kaupinis
- Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Monika Jazdauskaitė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Thermo Fisher Scientific Baltics, Vilnius, Lithuania
| | - Raminta Mineikaitė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Mindaugas Valius
- Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Viktoras Masevičius
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Vilnius, Lithuania
| | - Giedrius Vilkaitis
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
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20
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Wang YS, Kumari M, Chen GH, Hong MH, Yuan JPY, Tsai JL, Wu HC. mRNA-based vaccines and therapeutics: an in-depth survey of current and upcoming clinical applications. J Biomed Sci 2023; 30:84. [PMID: 37805495 PMCID: PMC10559634 DOI: 10.1186/s12929-023-00977-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Accepted: 09/29/2023] [Indexed: 10/09/2023] Open
Abstract
mRNA-based drugs have tremendous potential as clinical treatments, however, a major challenge in realizing this drug class will promise to develop methods for safely delivering the bioactive agents with high efficiency and without activating the immune system. With regard to mRNA vaccines, researchers have modified the mRNA structure to enhance its stability and promote systemic tolerance of antigenic presentation in non-inflammatory contexts. Still, delivery of naked modified mRNAs is inefficient and results in low levels of antigen protein production. As such, lipid nanoparticles have been utilized to improve delivery and protect the mRNA cargo from extracellular degradation. This advance was a major milestone in the development of mRNA vaccines and dispelled skepticism about the potential of this technology to yield clinically approved medicines. Following the resounding success of mRNA vaccines for COVID-19, many other mRNA-based drugs have been proposed for the treatment of a variety of diseases. This review begins with a discussion of mRNA modifications and delivery vehicles, as well as the factors that influence administration routes. Then, we summarize the potential applications of mRNA-based drugs and discuss further key points pertaining to preclinical and clinical development of mRNA drugs targeting a wide range of diseases. Finally, we discuss the latest market trends and future applications of mRNA-based drugs.
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Affiliation(s)
- Yu-Shiuan Wang
- Institute of Cellular and Organismic Biology, Academia Sinica, No. 128, Academia Road, Section 2, Nankang, Taipei, 11529, Taiwan
| | - Monika Kumari
- Institute of Cellular and Organismic Biology, Academia Sinica, No. 128, Academia Road, Section 2, Nankang, Taipei, 11529, Taiwan
| | - Guan-Hong Chen
- Biomedical Translation Research Center (BioTReC), Academia Sinica, Taipei, 11571, Taiwan
| | - Ming-Hsiang Hong
- Biomedical Translation Research Center (BioTReC), Academia Sinica, Taipei, 11571, Taiwan
| | - Joyce Pei-Yi Yuan
- Biomedical Translation Research Center (BioTReC), Academia Sinica, Taipei, 11571, Taiwan
| | - Jui-Ling Tsai
- Institute of Cellular and Organismic Biology, Academia Sinica, No. 128, Academia Road, Section 2, Nankang, Taipei, 11529, Taiwan
| | - Han-Chung Wu
- Institute of Cellular and Organismic Biology, Academia Sinica, No. 128, Academia Road, Section 2, Nankang, Taipei, 11529, Taiwan.
- Biomedical Translation Research Center (BioTReC), Academia Sinica, Taipei, 11571, Taiwan.
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21
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Abstract
RNA modification is manifested as chemically altered nucleotides, widely exists in diverse natural RNAs, and is closely related to RNA structure and function. Currently, mRNA-based vaccines have received great attention and rapid development as novel and mighty fighters against various diseases including cancer. The achievement of RNA vaccines in clinical application is largely attributed to some methodological innovations including the incorporation of modified nucleotides into the synthetic RNA. The selection of optimal RNA modifications aimed at reducing the instability and immunogenicity of RNA molecules is a very critical task to improve the efficacy and safety of mRNA vaccines. This review summarizes the functions of RNA modifications and their application in mRNA vaccines, highlights recent advances of mRNA vaccines in cancer immunotherapy, and provides perspectives for future development of mRNA vaccines in the context of personalized tumor therapy.
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Affiliation(s)
- Yingxue Mei
- Institute of Cancer Stem Cell, Cancer Center, Dalian Medical University, Dalian, 116044, Liaoning, People's Republic of China
| | - Xiang Wang
- Institute of Cancer Stem Cell, Cancer Center, Dalian Medical University, Dalian, 116044, Liaoning, People's Republic of China.
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22
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Sun H, Li K, Liu C, Yi C. Regulation and functions of non-m 6A mRNA modifications. Nat Rev Mol Cell Biol 2023; 24:714-731. [PMID: 37369853 DOI: 10.1038/s41580-023-00622-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2023] [Indexed: 06/29/2023]
Abstract
Nucleobase modifications are prevalent in eukaryotic mRNA and their discovery has resulted in the emergence of epitranscriptomics as a research field. The most abundant internal (non-cap) mRNA modification is N6-methyladenosine (m6A), the study of which has revolutionized our understanding of post-transcriptional gene regulation. In addition, numerous other mRNA modifications are gaining great attention because of their major roles in RNA metabolism, immunity, development and disease. In this Review, we focus on the regulation and function of non-m6A modifications in eukaryotic mRNA, including pseudouridine (Ψ), N6,2'-O-dimethyladenosine (m6Am), N1-methyladenosine (m1A), inosine, 5-methylcytidine (m5C), N4-acetylcytidine (ac4C), 2'-O-methylated nucleotide (Nm) and internal N7-methylguanosine (m7G). We highlight their regulation, distribution, stoichiometry and known roles in mRNA metabolism, such as mRNA stability, translation, splicing and export. We also discuss their biological consequences in physiological and pathological processes. In addition, we cover research techniques to further study the non-m6A mRNA modifications and discuss their potential future applications.
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Affiliation(s)
- Hanxiao Sun
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Kai Li
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Cong Liu
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Chengqi Yi
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China.
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.
- Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.
- Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.
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23
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Wang J, Chew BLA, Lai Y, Dong H, Xu L, Liu Y, Fu XY, Lin Z, Shi PY, Lu TK, Luo D, Jaffrey SR, Dedon PC. A systems-level mass spectrometry-based technique for accurate and sensitive quantification of the RNA cap epitranscriptome. Nat Protoc 2023; 18:2671-2698. [PMID: 37567932 DOI: 10.1038/s41596-023-00857-0] [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: 08/11/2021] [Accepted: 04/26/2023] [Indexed: 08/13/2023]
Abstract
Chemical modifications of transcripts with a 5' cap occur in all organisms and function in many aspects of RNA metabolism. To facilitate analysis of RNA caps, we developed a systems-level mass spectrometry-based technique, CapQuant, for accurate and sensitive quantification of the cap epitranscriptome. The protocol includes the addition of stable isotope-labeled cap nucleotides (CNs) to RNA, enzymatic hydrolysis of endogenous RNA to release CNs, and off-line enrichment of CNs by ion-pairing high-pressure liquid chromatography, followed by a 17 min chromatography-coupled tandem quadrupole mass spectrometry run for the identification and quantification of individual CNs. The total time required for the protocol can be up to 7 d. In this approach, 26 CNs can be quantified in eukaryotic poly(A)-tailed RNA, bacterial total RNA and viral RNA. This protocol can be modified to analyze other types of RNA and RNA from in vitro sources. CapQuant stands out from other methods in terms of superior specificity, sensitivity and accuracy, and it is not limited to individual caps nor does it require radiolabeling. Thanks to its unique capability of accurately and sensitively quantifying RNA caps on a systems level, CapQuant can reveal both the RNA cap landscape and the transcription start site distribution of capped RNA in a broad range of settings.
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Affiliation(s)
- Jin Wang
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, People's Republic of China.
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore.
- Institute of Biomedical Sciences, Inner Mongolia University, Hohhot, China.
| | - Bing Liang Alvin Chew
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- NTU Institute of Health Technologies, Interdisciplinary Graduate Programme, Nanyang Technological University, Singapore, Singapore
| | - Yong Lai
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
- Department of Chemical and Biological Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | | | - Luang Xu
- Cancer Science Institute of Singapore, Singapore, Singapore
- School of Life Science and Technology, Shanghai Institute of Biochemistry and Cell Biology, Shanghai, China
| | - Yu Liu
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, People's Republic of China
| | - Xin-Yuan Fu
- Cancer Science Institute of Singapore, Singapore, Singapore
- Generos Pharmaceutical Co. Ltd, Hangzhou, China
| | - Zhenguo Lin
- Department of Biology, Saint Louis University, St. Louis, MO, USA
| | - Pei-Yong Shi
- Departments of Biochemistry & Molecular Biology and Pharmacology & Toxicology, and Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA
- GlaxoSmithKline, Rockville, MD, USA
| | - Timothy K Lu
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
- Synthetic Biology Center, Departments of Biological Engineering and Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
- Senti Bio, San Francisco, CA, USA
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Samie R Jaffrey
- Department of Pharmacology, Weill Medical College, Cornell University, New York, NY, USA
| | - Peter C Dedon
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore.
- Dept. of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
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24
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Schweibenz BD, Solotchi M, Hanpude P, Devarkar S, Patel S. RIG-I recognizes metabolite-capped RNAs as signaling ligands. Nucleic Acids Res 2023; 51:8102-8114. [PMID: 37326006 PMCID: PMC10450190 DOI: 10.1093/nar/gkad518] [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: 10/06/2022] [Accepted: 06/12/2023] [Indexed: 06/17/2023] Open
Abstract
The innate immune receptor RIG-I recognizes 5'-triphosphate double-stranded RNAs (5' PPP dsRNA) as pathogenic RNAs. Such RNA-ends are present in viral genomes and replication intermediates, and they activate the RIG-I signaling pathway to produce a potent interferon response essential for viral clearance. Endogenous mRNAs cap the 5' PPP-end with m7G and methylate the 2'-O-ribose to evade RIG-I, preventing aberrant immune responses deleterious to the cell. Recent studies have identified RNAs in cells capped with metabolites such as NAD+, FAD and dephosphoCoA. Whether RIG-I recognizes these metabolite-capped RNAs has not been investigated. Here, we describe a strategy to make metabolite-capped RNAs free from 5' PPP dsRNA contamination, using in vitro transcription initiated with metabolites. Mechanistic studies show that metabolite-capped RNAs have a high affinity for RIG-I, stimulating the ATPase activity at comparable levels to 5' PPP dsRNA. Cellular signaling assays show that the metabolite-capped RNAs potently stimulate the innate antiviral immune response. This demonstrates that RIG-I can tolerate diphosphate-linked, capped RNAs with bulky groups at the 5' RNA end. This novel class of RNAs that stimulate RIG-I signaling may have cellular roles in activating the interferon response and may be exploited with proper functionalities for RIG-I-related RNA therapeutics.
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Affiliation(s)
- Brandon D Schweibenz
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
- Graduate School of Biomedical Sciences at the Robert Wood Johnson Medical School of Rutgers University, USA
| | - Mihai Solotchi
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
- Graduate School of Biomedical Sciences at the Robert Wood Johnson Medical School of Rutgers University, USA
| | - Pranita Hanpude
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
| | - Swapnil C Devarkar
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
- Graduate School of Biomedical Sciences at the Robert Wood Johnson Medical School of Rutgers University, USA
| | - Smita S Patel
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
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25
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Wolfram-Schauerte M, Pozhydaieva N, Grawenhoff J, Welp LM, Silbern I, Wulf A, Billau FA, Glatter T, Urlaub H, Jäschke A, Höfer K. A viral ADP-ribosyltransferase attaches RNA chains to host proteins. Nature 2023; 620:1054-1062. [PMID: 37587340 PMCID: PMC10468400 DOI: 10.1038/s41586-023-06429-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 07/12/2023] [Indexed: 08/18/2023]
Abstract
The mechanisms by which viruses hijack the genetic machinery of the cells they infect are of current interest. When bacteriophage T4 infects Escherichia coli, it uses three different adenosine diphosphate (ADP)-ribosyltransferases (ARTs) to reprogram the transcriptional and translational apparatus of the host by ADP-ribosylation using nicotinamide adenine dinucleotide (NAD) as a substrate1,2. NAD has previously been identified as a 5' modification of cellular RNAs3-5. Here we report that the T4 ART ModB accepts not only NAD but also NAD-capped RNA (NAD-RNA) as a substrate and attaches entire RNA chains to acceptor proteins in an 'RNAylation' reaction. ModB specifically RNAylates the ribosomal proteins rS1 and rL2 at defined Arg residues, and selected E. coli and T4 phage RNAs are linked to rS1 in vivo. T4 phages that express an inactive mutant of ModB have a decreased burst size and slowed lysis of E. coli. Our findings reveal a distinct biological role for NAD-RNA, namely the activation of the RNA for enzymatic transfer to proteins. The attachment of specific RNAs to ribosomal proteins might provide a strategy for the phage to modulate the host's translation machinery. This work reveals a direct connection between RNA modification and post-translational protein modification. ARTs have important roles far beyond viral infections6, so RNAylation may have far-reaching implications.
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Affiliation(s)
- Maik Wolfram-Schauerte
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | | | - Julia Grawenhoff
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Luisa M Welp
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Clinical Chemistry, University Medical Center, Göttingen, Germany
| | - Ivan Silbern
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Clinical Chemistry, University Medical Center, Göttingen, Germany
| | - Alexander Wulf
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Franziska A Billau
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Timo Glatter
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Clinical Chemistry, University Medical Center, Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), Georg-August-University, Göttingen, Germany
| | - Andres Jäschke
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany.
| | - Katharina Höfer
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany.
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany.
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26
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Sherwood AV, Rivera-Rangel LR, Ryberg LA, Larsen HS, Anker KM, Costa R, Vågbø CB, Jakljevič E, Pham LV, Fernandez-Antunez C, Indrisiunaite G, Podolska-Charlery A, Grothen JER, Langvad NW, Fossat N, Offersgaard A, Al-Chaer A, Nielsen L, Kuśnierczyk A, Sølund C, Weis N, Gottwein JM, Holmbeck K, Bottaro S, Ramirez S, Bukh J, Scheel TKH, Vinther J. Hepatitis C virus RNA is 5'-capped with flavin adenine dinucleotide. Nature 2023:10.1038/s41586-023-06301-3. [PMID: 37407817 DOI: 10.1038/s41586-023-06301-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 06/08/2023] [Indexed: 07/07/2023]
Abstract
RNA viruses have evolved elaborate strategies to protect their genomes, including 5' capping. However, until now no RNA 5' cap has been identified for hepatitis C virus1,2 (HCV), which causes chronic infection, liver cirrhosis and cancer3. Here we demonstrate that the cellular metabolite flavin adenine dinucleotide (FAD) is used as a non-canonical initiating nucleotide by the viral RNA-dependent RNA polymerase, resulting in a 5'-FAD cap on the HCV RNA. The HCV FAD-capping frequency is around 75%, which is the highest observed for any RNA metabolite cap across all kingdoms of life4-8. FAD capping is conserved among HCV isolates for the replication-intermediate negative strand and partially for the positive strand. It is also observed in vivo on HCV RNA isolated from patient samples and from the liver and serum of a human liver chimeric mouse model. Furthermore, we show that 5'-FAD capping protects RNA from RIG-I mediated innate immune recognition but does not stabilize the HCV RNA. These results establish capping with cellular metabolites as a novel viral RNA-capping strategy, which could be used by other viruses and affect anti-viral treatment outcomes and persistence of infection.
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Affiliation(s)
- Anna V Sherwood
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Lizandro R Rivera-Rangel
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Line A Ryberg
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Helena S Larsen
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Klara M Anker
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Rui Costa
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Cathrine B Vågbø
- Proteomics and Modomics Experimental Core (PROMEC), Norwegian University of Science and Technology and the Central Norway Regional Health Authority, Trondheim, Norway
| | - Eva Jakljevič
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Long V Pham
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Carlota Fernandez-Antunez
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Gabriele Indrisiunaite
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Agnieszka Podolska-Charlery
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Julius E R Grothen
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Nicklas W Langvad
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Nicolas Fossat
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Anna Offersgaard
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Amal Al-Chaer
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Louise Nielsen
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Anna Kuśnierczyk
- Proteomics and Modomics Experimental Core (PROMEC), Norwegian University of Science and Technology and the Central Norway Regional Health Authority, Trondheim, Norway
| | - Christina Sølund
- Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen N, Denmark
| | - Nina Weis
- Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen N, Denmark
| | - Judith M Gottwein
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Kenn Holmbeck
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Sandro Bottaro
- Section for Biomolecular Sciences, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Santseharay Ramirez
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark.
| | - Troels K H Scheel
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, University of Copenhagen, Copenhagen N, Denmark.
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY, USA.
| | - Jeppe Vinther
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, Copenhagen N, Denmark.
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27
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Abstract
Chemical modifications on mRNA represent a critical layer of gene expression regulation. Research in this area has continued to accelerate over the last decade, as more modifications are being characterized with increasing depth and breadth. mRNA modifications have been demonstrated to influence nearly every step from the early phases of transcript synthesis in the nucleus through to their decay in the cytoplasm, but in many cases, the molecular mechanisms involved in these processes remain mysterious. Here, we highlight recent work that has elucidated the roles of mRNA modifications throughout the mRNA life cycle, describe gaps in our understanding and remaining open questions, and offer some forward-looking perspective on future directions in the field.
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Affiliation(s)
- Wendy V Gilbert
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, Connecticut, USA;
| | - Sigrid Nachtergaele
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut, USA;
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28
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Lukaszewicz M, Mrozek AF, Bojarska E, Stelmach J, Stepinski J, Darzynkiewicz E. Contribution of Nudt12 enzyme to differentially methylated dinucleotides of 5'RNA cap structure. Biochim Biophys Acta Gen Subj 2023:130400. [PMID: 37301333 DOI: 10.1016/j.bbagen.2023.130400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/17/2023] [Accepted: 06/04/2023] [Indexed: 06/12/2023]
Abstract
Recent findings have substantially broadened our knowledge about the diversity of modifications of the 5'end of RNAs, an issue generally attributed to mRNA cap structure (m7GpppN). Nudt12 is one of the recently described new enzymatic activities involved in cap metabolism. However, in contrast to its roles in metabolite-cap turnover (e.g., NAD-cap) and NADH/NAD metabolite hydrolysis, little is known regarding its hydrolytic activity towards dinucleotide cap structures. In order to gain further insight into this Nudt12 activity, comprehensive analysis with a spectrum of cap-like dinucleotides was performed with respect to different nucleotide types adjacent to the (m7)G moiety and its methylation status. Among the tested compounds, GpppA, GpppAm, and Gpppm6Am were identified as novel potent Nudt12 substrates, with KM values in the same range as that of NADH. Interestingly, substrate inhibition of Nudt12 catalytic activity was detected in the case of the GpppG dinucleotide, a phenomenon not reported to date. Finally, comparison of Nudt12 with DcpS and Nud16, two other enzymes with known activity on dinucleotide cap structures, revealed their overlapping and more specific substrates. Altogether, these findings provide a basis for clarifying the role of Nudt12 in cap-like dinucleotide turnover.
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Affiliation(s)
- Maciej Lukaszewicz
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland.
| | - Aleksandra-Ferenc Mrozek
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Elzbieta Bojarska
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Joanna Stelmach
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Janusz Stepinski
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Edward Darzynkiewicz
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland; Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
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29
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Liang S, Almohammed R, Cowling VH. The RNA cap methyltransferases RNMT and CMTR1 co-ordinate gene expression during neural differentiation. Biochem Soc Trans 2023:233029. [PMID: 37145036 DOI: 10.1042/bst20221154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 04/03/2023] [Accepted: 04/18/2023] [Indexed: 05/06/2023]
Abstract
Regulation of RNA cap formation has potent impacts on gene regulation, controlling which transcripts are expressed, processed and translated into protein. Recently, the RNA cap methyltransferases RNA guanine-7 methyltransferase (RNMT) and cap-specific mRNA (nucleoside-2'-O-)-methyltransferase 1 (CMTR1) have been found to be independently regulated during embryonic stem (ES) cell differentiation controlling the expression of overlapping and distinct protein families. During neural differentiation, RNMT is repressed and CMTR1 is up-regulated. RNMT promotes expression of the pluripotency-associated gene products; repression of the RNMT complex (RNMT-RAM) is required for repression of these RNAs and proteins during differentiation. The predominant RNA targets of CMTR1 encode the histones and ribosomal proteins (RPs). CMTR1 up-regulation is required to maintain the expression of histones and RPs during differentiation and to maintain DNA replication, RNA translation and cell proliferation. Thus the co-ordinate regulation of RNMT and CMTR1 is required for different aspects of ES cell differentiation. In this review, we discuss the mechanisms by which RNMT and CMTR1 are independently regulated during ES cell differentiation and explore how this influences the co-ordinated gene regulation required of emerging cell lineages.
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Affiliation(s)
- Shang Liang
- Cancer Research UK Beatson Institute, Glasgow, U.K
- School of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, U.K
| | - Rajaei Almohammed
- Cancer Research UK Beatson Institute, Glasgow, U.K
- School of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, U.K
| | - Victoria H Cowling
- Cancer Research UK Beatson Institute, Glasgow, U.K
- School of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, U.K
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30
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Mititelu MB, Hudeček O, Gozdek A, Benoni R, Nešuta O, Krasnodębski S, Kufel J, Cahová H. Arabidopsis thaliana NudiXes have RNA-decapping activity. RSC Chem Biol 2023; 4:223-228. [PMID: 36908703 PMCID: PMC9994101 DOI: 10.1039/d2cb00213b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 01/02/2023] [Indexed: 01/11/2023] Open
Abstract
Recent discoveries of various noncanonical RNA caps, such as dinucleoside polyphosphates (Np n N), coenzyme A (CoA), and nicotinamide adenine dinucleotide (NAD) in all domains of life have led to a revision of views on RNA cap function and metabolism. Enzymes from the NudiX family capable of hydrolyzing a polyphosphate backbone attached to a nucleoside are the strongest candidates for degradation of noncanonically capped RNA. The model plant organism Arabidopsis thaliana encodes as many as 28 NudiX enzymes. For most of them, only in vitro substrates in the form of small molecules are known. In our study, we focused on four A. thaliana NudiX enzymes (AtNUDT6, AtNUDT7, AtNUDT19 and AtNUDT27), and we studied whether these enzymes can cleave RNA capped with Np n Ns (Ap2-5A, Gp3-4G, Ap3-5G, m7Gp3G, m7Gp3A), CoA, ADP-ribose, or NAD(H). While AtNUDT19 preferred NADH-RNA over other types of capped RNA, AtNUDT6 and AtNUDT7 preferentially cleaved Ap4A-RNA. The most powerful decapping enzyme was AtNUDT27, which cleaved almost all types of capped RNA at a tenfold lower concentration than the other enzymes. We also compared cleavage efficiency of each enzyme on free small molecules with RNA capped with corresponding molecules. We found that AtNUDT6 prefers free Ap4A, while AtNUDT7 preferentially cleaved Ap4A-RNA. These findings show that NudiX enzymes may act as RNA-decapping enzymes in A. thaliana and that other noncanonical RNA caps such as Ap4A and NADH should be searched for in plant RNA.
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Affiliation(s)
- Maria-Bianca Mititelu
- Institute of Organic Chemistry and Biochemistry of the CAS Flemingovo náměstí 2 Prague 6 Czechia .,Charles University, Faculty of Science, Department of Cell Biology Viničná 7 Prague 2 Czechia
| | - Oldřich Hudeček
- Institute of Organic Chemistry and Biochemistry of the CAS Flemingovo náměstí 2 Prague 6 Czechia
| | - Agnieszka Gozdek
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw Pawinskiego 5a Warsaw 02-106 Poland
| | - Roberto Benoni
- Institute of Organic Chemistry and Biochemistry of the CAS Flemingovo náměstí 2 Prague 6 Czechia
| | - Ondřej Nešuta
- Institute of Organic Chemistry and Biochemistry of the CAS Flemingovo náměstí 2 Prague 6 Czechia
| | - Szymon Krasnodębski
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw Pawinskiego 5a Warsaw 02-106 Poland
| | - Joanna Kufel
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw Pawinskiego 5a Warsaw 02-106 Poland
| | - Hana Cahová
- Institute of Organic Chemistry and Biochemistry of the CAS Flemingovo náměstí 2 Prague 6 Czechia
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31
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Anreiter I, Tian YW, Soller M. The cap epitranscriptome: Early directions to a complex life as mRNA. Bioessays 2023; 45:e2200198. [PMID: 36529693 DOI: 10.1002/bies.202200198] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/07/2022] [Accepted: 12/08/2022] [Indexed: 12/23/2022]
Abstract
Animal, protist and viral messenger RNAs (mRNAs) are most prominently modified at the beginning by methylation of cap-adjacent nucleotides at the 2'-O-position of the ribose (cOMe) by dedicated cap methyltransferases (CMTrs). If the first nucleotide of an mRNA is an adenosine, PCIF1 can methylate at the N6 -position (m6 A), while internally the Mettl3/14 writer complex can methylate. These modifications are introduced co-transcriptionally to affect many aspects of gene expression including localisation to synapses and local translation. Of particular interest, transcription start sites of many genes are heterogeneous leading to sequence diversity at the beginning of mRNAs, which together with cOMe and m6 Am could constitute an extensive novel layer of gene expression control. Given the role of cOMe and m6 A in local gene expression at synapses and higher brain functions including learning and memory, such code could be implemented at the transcriptional level for lasting memories through local gene expression at synapses.
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Affiliation(s)
- Ina Anreiter
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, Canada
| | - Yuan W Tian
- Birmingham Centre for Genome Biology, University of Birmingham, Birmingham, UK.,School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - Matthias Soller
- Birmingham Centre for Genome Biology, University of Birmingham, Birmingham, UK.,School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
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32
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Wolfram-Schauerte M, Höfer K. NAD-capped RNAs - a redox cofactor meets RNA. Trends Biochem Sci 2023; 48:142-155. [PMID: 36068130 DOI: 10.1016/j.tibs.2022.08.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/03/2022] [Accepted: 08/04/2022] [Indexed: 01/25/2023]
Abstract
RNA modifications immensely expand the diversity of the transcriptome, thereby influencing the function, localization, and stability of RNA. One prominent example of an RNA modification is the eukaryotic cap located at the 5' terminus of mRNAs. Interestingly, the redox cofactor NAD can be incorporated into RNA by RNA polymerase in vitro. The existence of NAD-modified RNAs in vivo was confirmed using liquid chromatography and mass spectrometry (LC-MS). In the past few years novel technologies and methods have characterized NAD as a cap-like RNA structure and enabled the investigation of NAD-capped RNAs (NAD-RNAs) in a physiological context. We highlight the identification of NAD-RNAs as well as the regulation and functions of this epitranscriptomic mark in all domains of life.
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Affiliation(s)
| | - Katharina Höfer
- Max-Planck-Institute for Terrestrial Microbiology, Marburg, 35043, Hessen, Germany.
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33
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Regulation of Gene Expression by m6Am RNA Modification. Int J Mol Sci 2023; 24:ijms24032277. [PMID: 36768600 PMCID: PMC9916840 DOI: 10.3390/ijms24032277] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/17/2023] [Accepted: 01/21/2023] [Indexed: 01/26/2023] Open
Abstract
The field of RNA modification, also referred to as "epitranscriptomics," is gaining more and more interest from the scientific community. More than 160 chemical modifications have been identified in RNA molecules, but the functional significance of most of them still needs to be clarified. In this review, we discuss the role of N6,2'-O-dimethyladenosine (m6Am) in gene expression regulation. m6Am is present in the first transcribed nucleotide close to the cap in many mRNAs and snRNAs in mammals and as internal modification in the snRNA U2. The writer and eraser proteins for these modifications have been recently identified and their deletions have been utilized to understand their contributions in gene expression regulation. While the role of U2 snRNA-m6Am in splicing regulation has been reported by different independent studies, conflicting data were found for the role of cap-associated m6Am in mRNA stability and translation. However, despite the open debate on the role of m6Am in mRNA expression, the modulation of regulators produced promising results in cancer cells. We believe that the investigation on m6Am will continue to yield relevant results in the future.
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34
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Muthmann N, Albers M, Rentmeister A. CAPturAM, a Chemo-Enzymatic Strategy for Selective Enrichment and Detection of Physiological CAPAM-Targets. Angew Chem Int Ed Engl 2023; 62:e202211957. [PMID: 36282111 PMCID: PMC10107118 DOI: 10.1002/anie.202211957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/23/2022] [Accepted: 10/25/2022] [Indexed: 11/07/2022]
Abstract
Modified nucleotides impact all aspects of eukaryotic mRNAs and contribute to regulation of gene expression at the transcriptional and translational level. At the 5' cap, adenosine as first transcribed nucleotide is often N6 -methyl-2'-O-methyl adenosine (m6 Am ). This modification is tissue dependent and reversible, pointing to a regulatory function. CAPAM was recently identified as methyltransferase responsible for m6 Am formation, however, the direct assignment of its target transcripts proves difficult. Antibodies do not discriminate between internal N6 -methyl adenosine (m6 A) and m6 Am . Here we present CAPturAM, an antibody-free chemical biology approach for direct enrichment and probing of physiological CAPAM-targets. We harness CAPAM's cosubstrate promiscuity to install propargyl groups on its targets. Subsequent functionalization with an affinity handle allows for their enrichment. Using wildtype and CAPAM-/- cells, we successfully applied CAPturAM to confirm or disprove CAPAM-targets, facilitating the verification and identification of CAPAM targets.
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Affiliation(s)
- Nils Muthmann
- Department of Chemistry, Institute of Biochemistry, University of Münster, Corrensstrasse 36, 48149, Münster, Germany
| | - Marvin Albers
- Department of Chemistry, Institute of Biochemistry, University of Münster, Corrensstrasse 36, 48149, Münster, Germany
| | - Andrea Rentmeister
- Department of Chemistry, Institute of Biochemistry, University of Münster, Corrensstrasse 36, 48149, Münster, Germany
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35
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Niu K, Zhang J, Ge S, Li D, Sun K, You Y, Qiu J, Wang K, Wang X, Liu R, Liu Y, Li B, Zhu ZJ, Qu L, Jiang H, Liu N. ONE-seq: epitranscriptome and gene-specific profiling of NAD-capped RNA. Nucleic Acids Res 2022; 51:e12. [PMID: 36477375 PMCID: PMC9881147 DOI: 10.1093/nar/gkac1136] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 11/01/2022] [Accepted: 11/15/2022] [Indexed: 12/13/2022] Open
Abstract
The hub metabolite, nicotinamide adenine dinucleotide (NAD), can be used as an initiating nucleotide in RNA synthesis to result in NAD-capped RNAs (NAD-RNA). Since NAD has been heightened as one of the most essential modulators in aging and various age-related diseases, its attachment to RNA might indicate a yet-to-be discovered mechanism that impacts adult life-course. However, the unknown identity of NAD-linked RNAs in adult and aging tissues has hindered functional studies. Here, we introduce ONE-seq method to identify the RNA transcripts that contain NAD cap. ONE-seq has been optimized to use only one-step chemo-enzymatic biotinylation, followed by streptavidin capture and the nudix phosphohydrolase NudC-catalyzed elution, to specifically recover NAD-capped RNAs for epitranscriptome and gene-specific analyses. Using ONE-seq, we discover more than a thousand of previously unknown NAD-RNAs in the mouse liver and reveal epitranscriptome-wide dynamics of NAD-RNAs with age. ONE-seq empowers the identification of NAD-capped RNAs that are responsive to distinct physiological states, facilitating functional investigation into this modification.
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Affiliation(s)
| | | | | | | | - Kunfeng Sun
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Rd., Pudong, Shanghai 201210, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yingnan You
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Rd., Pudong, Shanghai 201210, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiaqian Qiu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Rd., Pudong, Shanghai 201210, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kun Wang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Rd., Pudong, Shanghai 201210, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xueting Wang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Rd., Pudong, Shanghai 201210, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Liu
- Singlera Genomics, 500 Fu Rong Hua Rd., Pudong, Shanghai 201204, China
| | - Yandong Liu
- Department of Vascular and Endovascular Surgery, Chang Zheng Hospital, Naval Medical University, Shanghai 200003, China
| | - Bing Li
- IH Bluex Technology, 58 Xiang Cheng Road, Shanghai 200122, China
| | - Zheng-Jiang Zhu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 100 Hai Ke Rd., Pudong, Shanghai 201210, China,Shanghai Key Laboratory of Aging Studies, 100 Hai Ke Rd., Pudong, Shanghai 201210, China
| | - Lefeng Qu
- Correspondence may also be addressed to Lefeng Qu. Tel: +86 21 6361 0109;
| | - Hong Jiang
- Correspondence may also be addressed to Hong Jiang. Tel: +86 21 6858 2396;
| | - Nan Liu
- To whom correspondence should be addressed. Tel: +86 21 6858 2308;
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36
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van den Elzen AMG, Watson MJ, Thoreen CC. mRNA 5' terminal sequences drive 200-fold differences in expression through effects on synthesis, translation and decay. PLoS Genet 2022; 18:e1010532. [PMID: 36441824 PMCID: PMC9731452 DOI: 10.1371/journal.pgen.1010532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/08/2022] [Accepted: 11/15/2022] [Indexed: 11/30/2022] Open
Abstract
mRNA regulatory sequences control gene expression at multiple levels including translation initiation and mRNA decay. The 5' terminal sequences of mRNAs have unique regulatory potential because of their proximity to key post-transcriptional regulators. Here we have systematically probed the function of 5' terminal sequences in gene expression in human cells. Using a library of reporter mRNAs initiating with all possible 7-mer sequences at their 5' ends, we find an unexpected impact on transcription that underlies 200-fold differences in mRNA expression. Library sequences that promote high levels of transcription mirrored those found in native mRNAs and define two basic classes with similarities to classic Initiator (Inr) and TCT core promoter motifs. By comparing transcription, translation and decay rates, we identify sequences that are optimized for both efficient transcription and growth-regulated translation and stability, including variants of terminal oligopyrimidine (TOP) motifs. We further show that 5' sequences of endogenous mRNAs are enriched for multi-functional TCT/TOP hybrid sequences. Together, our results reveal how 5' sequences define two general classes of mRNAs with distinct growth-responsive profiles of expression across synthesis, translation and decay.
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Affiliation(s)
- Antonia M. G. van den Elzen
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut, United States of America
| | - Maegan J. Watson
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut, United States of America
| | - Carson C. Thoreen
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut, United States of America
- * E-mail:
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37
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Mattay J. Noncanonical metabolite RNA caps: Classification, quantification, (de)capping, and function. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1730. [PMID: 35675554 DOI: 10.1002/wrna.1730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/11/2022] [Accepted: 03/15/2022] [Indexed: 06/15/2023]
Abstract
The 5' cap of eukaryotic mRNA is a hallmark for cellular functions from mRNA stability to translation. However, the discovery of novel 5'-terminal RNA caps derived from cellular metabolites has challenged this long-standing singularity in both eukaryotes and prokaryotes. Reminiscent of the 7-methylguanosine (m7G) cap structure, these noncanonical caps originate from abundant coenzymes such as NAD, FAD, or CoA and from metabolites like dinucleoside polyphosphates (NpnN). As of now, the significance of noncanonical RNA caps is elusive: they differ for individual transcripts, occur in distinct types of RNA, and change in response to environmental stimuli. A thorough comparison of their prevalence, quantity, and characteristics is indispensable to define the distinct classes of metabolite-capped RNAs. This is achieved by a structured analysis of all present studies covering functional, quantitative, and sequencing data which help to uncover their biological impact. The biosynthetic strategies of noncanonical RNA capping and the elaborate decapping machinery reveal the regulation and turnover of metabolite-capped RNAs. With noncanonical capping being a universal and ancient phenomenon, organisms have developed diverging strategies to adapt metabolite-derived caps to their metabolic needs, but ultimately to establish noncanonical RNA caps as another intriguing layer of RNA regulation. This article is categorized under: RNA Processing > Capping and 5' End Modifications RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Turnover and Surveillance > Regulation of RNA Stability.
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Affiliation(s)
- Johanna Mattay
- Institute of Biochemistry, University of Münster, Münster, Germany
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38
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Dix TC, Haussmann IU, Brivio S, Nallasivan MP, HadzHiev Y, Müller F, Müller B, Pettitt J, Soller M. CMTr mediated 2'- O-ribose methylation status of cap-adjacent nucleotides across animals. RNA (NEW YORK, N.Y.) 2022; 28:1377-1390. [PMID: 35970556 PMCID: PMC9479742 DOI: 10.1261/rna.079317.122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Cap methyltransferases (CMTrs) O methylate the 2' position of the ribose (cOMe) of cap-adjacent nucleotides of animal, protist, and viral mRNAs. Animals generally have two CMTrs, whereas trypanosomes have three, and many viruses encode one in their genome. In the splice leader of mRNAs in trypanosomes, the first four nucleotides contain cOMe, but little is known about the status of cOMe in animals. Here, we show that cOMe is prominently present on the first two cap-adjacent nucleotides with species- and tissue-specific variations in Caenorhabditis elegans, honeybees, zebrafish, mouse, and human cell lines. In contrast, Drosophila contains cOMe primarily on the first cap-adjacent nucleotide. De novo RoseTTA modeling of CMTrs reveals close similarities of the overall structure and near identity for the catalytic tetrad, and for cap and cofactor binding for human, Drosophila and C. elegans CMTrs. Although viral CMTrs maintain the overall structure and catalytic tetrad, they have diverged in cap and cofactor binding. Consistent with the structural similarity, both CMTrs from Drosophila and humans methylate the first cap-adjacent nucleotide of an AGU consensus start. Because the second nucleotide is also methylated upon heat stress in Drosophila, these findings argue for regulated cOMe important for gene expression regulation.
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Affiliation(s)
- Thomas C Dix
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
- Birmingham Centre for Genome Biology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Irmgard U Haussmann
- Department of Life Science, Faculty of Health, Education and Life Sciences, Birmingham City University, Birmingham, B15 3TN, United Kingdom
| | - Sarah Brivio
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Mohannakarthik P Nallasivan
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
- Birmingham Centre for Genome Biology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Yavor HadzHiev
- Birmingham Centre for Genome Biology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
- School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, United Kingdom
| | - Ferenc Müller
- Birmingham Centre for Genome Biology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
- School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, United Kingdom
| | - Berndt Müller
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Jonathan Pettitt
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Matthias Soller
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
- Birmingham Centre for Genome Biology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
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39
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Sharma S, Yang J, Doamekpor SK, Grudizen-Nogalska E, Tong L, Kiledjian M. Identification of a novel deFADding activity in human, yeast and bacterial 5' to 3' exoribonucleases. Nucleic Acids Res 2022; 50:8807-8817. [PMID: 35904778 PMCID: PMC9410882 DOI: 10.1093/nar/gkac617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/18/2022] [Accepted: 07/21/2022] [Indexed: 11/19/2022] Open
Abstract
Identification of metabolite caps including FAD on the 5' end of RNA has uncovered a previously unforeseen intersection between cellular metabolism and gene expression. To understand the function of FAD caps in cellular physiology, we characterised the proteins interacting with FAD caps in budding yeast. Here we demonstrate that highly conserved 5'-3' exoribonucleases, Xrn1 and Rat1, physically interact with the RNA 5' FAD cap and both possess FAD cap decapping (deFADding) activity and subsequently degrade the resulting RNA. Xrn1 deFADding activity was also evident in human cells indicating its evolutionary conservation. Furthermore, we report that the recently identified bacterial 5'-3' exoribonuclease RNase AM also possesses deFADding activity that can degrade FAD-capped RNAs in vitro and in Escherichia coli cells. To gain a molecular understanding of the deFADding reaction, an RNase AM crystal structure with three manganese ions coordinated by a sulfate molecule and the active site amino acids was generated that provided details underlying hydrolysis of the FAD cap. Our findings reveal a general propensity for 5'-3' exoribonucleases to hydrolyse and degrade RNAs with 5' end noncanonical caps in addition to their well characterized 5' monophosphate RNA substrates indicating an intrinsic property of 5'-3' exoribonucleases.
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Affiliation(s)
- Sunny Sharma
- Department of Cell Biology and Neurosciences, Rutgers, University, Piscataway, NJ 08854, USA
| | - Jun Yang
- Department of Cell Biology and Neurosciences, Rutgers, University, Piscataway, NJ 08854, USA
| | - Selom K Doamekpor
- Department Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Ewa Grudizen-Nogalska
- Department of Cell Biology and Neurosciences, Rutgers, University, Piscataway, NJ 08854, USA
| | - Liang Tong
- Department Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Megerditch Kiledjian
- Department of Cell Biology and Neurosciences, Rutgers, University, Piscataway, NJ 08854, USA
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40
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Drazkowska K, Tomecki R, Warminski M, Baran N, Cysewski D, Depaix A, Kasprzyk R, Kowalska J, Jemielity J, Sikorski P. 2'-O-Methylation of the second transcribed nucleotide within the mRNA 5' cap impacts the protein production level in a cell-specific manner and contributes to RNA immune evasion. Nucleic Acids Res 2022; 50:9051-9071. [PMID: 36018811 PMCID: PMC9458431 DOI: 10.1093/nar/gkac722] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/02/2022] [Accepted: 08/16/2022] [Indexed: 12/24/2022] Open
Abstract
In mammals, m7G-adjacent nucleotides undergo extensive modifications. Ribose of the first or first and second transcribed nucleotides can be subjected to 2'-O-methylation to form cap1 or cap2, respectively. When the first transcribed nucleotide is 2'-O-methylated adenosine, it can be additionally modified to N6,2'-O-dimethyladenosine (m6Am). Recently, the crucial role of cap1 in distinguishing between 'self' and 'non-self' in mammalian cells during viral infection was revealed. Here, we attempted to understand the impact of cap methylations on RNA-related processes. Therefore, we synthesized tetranucleotide cap analogues and used them for RNA capping during in vitro transcription. Using this tool, we found that 2'-O-methylation of the second transcribed nucleotide within the mRNA 5' cap influences protein production levels in a cell-specific manner. This modification can strongly hamper protein biosynthesis or have no influence on protein production levels, depending on the cell line. Interestingly, 2'-O-methylation of the second transcribed nucleotide and the presence of m6Am as the first transcribed nucleotide serve as determinants that define transcripts as 'self' and contribute to transcript escape from the host innate immune response. Additionally, cap methylation status does not influence transcript affinity towards translation initiation factor eIF4E or in vitro susceptibility to decapping by DCP2; however, we observe the resistance of cap2-RNA to DXO (decapping exoribonuclease)-mediated decapping and degradation.
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Affiliation(s)
- Karolina Drazkowska
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Rafal Tomecki
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawinskiego 5a, 02-106 Warsaw, Poland
| | - Marcin Warminski
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Natalia Baran
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland,Department of Environmental Microbiology and Biotechnology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Dominik Cysewski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland,Clinical Research Centre, Medical University of Bialystok, M. Sklodowskiej-Curie 24a, 15-276 Bialystok, Poland
| | - Anaïs Depaix
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Renata Kasprzyk
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Joanna Kowalska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Jacek Jemielity
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Pawel J Sikorski
- To whom correspondence should be addressed. Tel: +48 22 55 43775; Fax: +48 22 55 43771;
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Depaix A, Grudzien-Nogalska E, Fedorczyk B, Kiledjian M, Jemielity J, Kowalska J. Preparation of RNAs with non-canonical 5' ends using novel di- and trinucleotide reagents for co-transcriptional capping. Front Mol Biosci 2022; 9:854170. [PMID: 36060251 PMCID: PMC9437278 DOI: 10.3389/fmolb.2022.854170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 07/06/2022] [Indexed: 12/04/2022] Open
Abstract
Many eukaryotic and some bacterial RNAs are modified at the 5' end by the addition of cap structures. In addition to the classic 7-methylguanosine 5' cap in eukaryotic mRNA, several non-canonical caps have recently been identified, including NAD-linked, FAD-linked, and UDP-glucose-linked RNAs. However, studies of the biochemical properties of these caps are impaired by the limited access to in vitro transcribed RNA probes of high quality, as the typical capping efficiencies with NAD or FAD dinucleotides achieved in the presence of T7 polymerase rarely exceed 50%, and pyrimidine derivatives are not incorporated because of promoter sequence limitations. To address this issue, we developed a series of di- and trinucleotide capping reagents and in vitro transcription conditions to provide straightforward access to unconventionally capped RNAs with improved 5'-end homogeneity. We show that because of the transcription start site flexibility of T7 polymerase, R1ppApG-type structures (where R1 is either nicotinamide riboside or riboflavin) are efficiently incorporated into RNA during transcription from dsDNA templates containing both φ 6.5 and φ 2.5 promoters and enable high capping efficiencies (∼90%). Moreover, uridine-initiated RNAs are accessible by transcription from templates containing the φ 6.5 promoter performed in the presence of R2ppUpG-type initiating nucleotides (where R2 is a sugar or phosphate moiety). We successfully employed this strategy to obtain several nucleotide-sugar-capped and uncapped RNAs. The capping reagents developed herein provide easy access to chemical probes to elucidate the biological roles of non-canonical RNA 5' capping.
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Affiliation(s)
- Anaïs Depaix
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
| | - Ewa Grudzien-Nogalska
- Department of Cell Biology and Neuroscience, Rutgers University, New York, NJ, United States
| | | | - Megerditch Kiledjian
- Department of Cell Biology and Neuroscience, Rutgers University, New York, NJ, United States
| | - Jacek Jemielity
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
| | - Joanna Kowalska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
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42
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Multiple Roles of m6A RNA Modification in Translational Regulation in Cancer. Int J Mol Sci 2022; 23:ijms23168971. [PMID: 36012237 PMCID: PMC9408962 DOI: 10.3390/ijms23168971] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022] Open
Abstract
Despite its discovery in the early 1970s, m6A modification within mRNA molecules has only powerfully entered the oncology field in recent years. This chemical modification can control all aspects of the maturation of mRNAs, both in the nucleus and in the cytoplasm. Thus, the alteration in expression levels of writers, erasers, and readers may significantly contribute to the alteration of gene expression observed in cancer. In particular, the activation of oncogenic pathways can lead to an alteration of the global rate of mRNA translation or the selective translation of specific mRNAs. In both cases, m6A can play an important role. In this review, we highlight the role of m6A in the regulation of translation by focusing on regulatory mechanisms and cancer-related functions of this novel but still controversial field.
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Petrov DP, Kaiser S, Kaiser S, Jung K. Opportunities and challenges to profile mRNA modifications in Escherichia coli. Chembiochem 2022; 23:e202200270. [PMID: 35822398 PMCID: PMC9542048 DOI: 10.1002/cbic.202200270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/12/2022] [Indexed: 11/23/2022]
Abstract
mRNA methylation is an important regulator of many physiological processes in eukaryotes but has not been studied in depth in prokaryotes. Working with bacterial mRNA is challenging because it lacks a poly(A)‐tail. However, methods for detecting RNA modifications, both sequencing and mass spectrometry, rely on efficient preparation of mRNA. Here, we compared size‐dependent separation by electrophoresis and rRNA depletion for enrichment of Escherichia coli mRNA. The purification success was monitored by qRT‐PCR and RNA sequencing. Neither method allowed complete removal of rRNA. Nevertheless, we were able to quantitatively analyze several modified nucleosides in the different RNA types. We found evidence for stress dependent RNA modification reprofiling in rRNA, but also several modified nucleosides in the mRNA enriched fractions showed significant changes.
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Affiliation(s)
| | - Steffen Kaiser
- Goethe-Universität Frankfurt am Main: Goethe-Universitat Frankfurt am Main, Pharmacy, GERMANY
| | - Stefanie Kaiser
- Goethe-Universität Frankfurt am Main: Goethe-Universitat Frankfurt am Main, Pharmacy, GERMANY
| | - Kirsten Jung
- Ludwig-Maximilians-Universitat Munchen, Biology, Grosshaderner Str. 2-4, 82152, Martinsried, GERMANY
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44
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Sáez Moreno D, Udi Q, Azeredo J, Domingues L. Towards T7 RNA polymerase (T7RNAP)-based expression system in yeast: challenges and opportunities. Bioengineered 2022; 13:14947-14959. [PMID: 37105766 DOI: 10.1080/21655979.2023.2180579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Abstract
During the last decades, we have witnessed unprecedented advances in biological engineering and synthetic biology. These disciplines aim to take advantage of gene pathway regulation and gene expression in different organisms, to enable cells to perform desired functions. Yeast has been widely utilized as a model for the study of eukaryotic protein expression while bacteriophage T7RNAP and its promoter constitute the preferred system for prokaryotic protein expression (such as pET-based expression systems). The ability to integrate a T7RNAP-based expression system in yeast could allow for a better understanding of gene regulation in eukaryotic cells, and potentially increase the efficiency and processivity of yeast as an expression system. However, the attempts for the creation of such a system have been unsuccessful to date. This review aims to: (i) summarize the efforts that, for many years, have been devoted to the creation of a T7RNAP-based yeast expression system and ii) provide an overview of the latest advances in knowledge of eukaryotic transcription and translation that could lead to the construction of a successful T7RNAP expression system in yeast. The completion of this new expression system would allow to further expand the toolkit of yeast in synthetic biology and ultimately contribute to boost yeast usage as a key cell factory in sustainable biorefinery and circular economy.
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Affiliation(s)
- David Sáez Moreno
- CEB-Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal
- LABBELS-Associate Laboratory, 4835-198, Guimarães, Braga, Portugal
| | - Qimron Udi
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Joana Azeredo
- CEB-Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal
- LABBELS-Associate Laboratory, 4835-198, Guimarães, Braga, Portugal
| | - Lucília Domingues
- CEB-Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal
- LABBELS-Associate Laboratory, 4835-198, Guimarães, Braga, Portugal
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45
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Dai X, Shen L. Advances and Trends in Omics Technology Development. Front Med (Lausanne) 2022; 9:911861. [PMID: 35860739 PMCID: PMC9289742 DOI: 10.3389/fmed.2022.911861] [Citation(s) in RCA: 68] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 05/09/2022] [Indexed: 12/11/2022] Open
Abstract
The human history has witnessed the rapid development of technologies such as high-throughput sequencing and mass spectrometry that led to the concept of “omics” and methodological advancement in systematically interrogating a cellular system. Yet, the ever-growing types of molecules and regulatory mechanisms being discovered have been persistently transforming our understandings on the cellular machinery. This renders cell omics seemingly, like the universe, expand with no limit and our goal toward the complete harness of the cellular system merely impossible. Therefore, it is imperative to review what has been done and is being done to predict what can be done toward the translation of omics information to disease control with minimal cell perturbation. With a focus on the “four big omics,” i.e., genomics, transcriptomics, proteomics, metabolomics, we delineate hierarchies of these omics together with their epiomics and interactomics, and review technologies developed for interrogation. We predict, among others, redoxomics as an emerging omics layer that views cell decision toward the physiological or pathological state as a fine-tuned redox balance.
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Abstract
The chemical modification of ribonucleotides plays an integral role in the biology of diverse viruses and their eukaryotic host cells. Mapping the precise identity, location, and abundance of modified ribonucleotides remains a key goal of many studies aimed at characterizing the function and importance of a given modification. While mapping of specific RNA modifications through short-read sequencing approaches has powered a wealth of new discoveries in the past decade, this approach is limited by inherent biases and an absence of linkage information. Moreover, in viral contexts, the challenge is increased due to the compact nature of viral genomes giving rise to many overlapping transcript isoforms that cannot be adequately resolved using short-read sequencing approaches. The recent emergence of nanopore sequencing, specifically the ability to directly sequence native RNAs from virus-infected host cells, provides not just a new methodology for mapping modified ribonucleotides but also a new conceptual framework for what can be derived from the resulting sequencing data. In this minireview, we provide a detailed overview of how nanopore direct RNA sequencing works, the computational approaches applied to identify modified ribonucleotides, and the core concepts underlying both. We further highlight recent studies that have applied this approach to interrogating viral biology and finish by discussing key experimental considerations and how we predict that these methodologies will continue to evolve.
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47
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Staphylococcus aureus Small RNAs Possess Dephospho-CoA 5′-Caps, but No CoAlation Marks. Noncoding RNA 2022; 8:ncrna8040046. [PMID: 35893229 PMCID: PMC9326634 DOI: 10.3390/ncrna8040046] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 06/23/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022] Open
Abstract
Novel features of coenzyme A (CoA) and its precursor, 3′-dephospho-CoA (dpCoA), recently became evident. dpCoA was found to attach to 5′-ends of small ribonucleic acids (dpCoA-RNAs) in two bacterial species (Escherichia coli and Streptomyces venezuelae). Furthermore, CoA serves, in addition to its well-established coenzymatic roles, as a ubiquitous posttranslational protein modification (‘CoAlation’), thought to prevent the irreversible oxidation of cysteines. Here, we first identified and quantified dpCoA-RNAs in the small RNA fraction of the human pathogen Staphylococcus aureus, using a newly developed enzymatic assay. We found that the amount of dpCoA caps was similar to that of the other two bacteria. We furthermore tested the hypothesis that, in the environment of a cell, the free thiol of the dpCoA-RNAs, as well as other sulfur-containing RNA modifications, may be oxidized by disulfide bond formation, e.g., with CoA. While we could not find evidence for such an ‘RNA CoAlation’, we observed that CoA disulfide reductase, the enzyme responsible for reducing CoA homodisulfides in S. aureus, did efficiently reduce several synthetic dpCoA-RNA disulfides to dpCoA-RNAs in vitro. This activity may imply a role in reversing RNA CoAlation.
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48
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Doamekpor SK, Sharma S, Kiledjian M, Tong L. Recent insights into noncanonical 5' capping and decapping of RNA. J Biol Chem 2022; 298:102171. [PMID: 35750211 PMCID: PMC9283932 DOI: 10.1016/j.jbc.2022.102171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/15/2022] [Accepted: 06/16/2022] [Indexed: 11/30/2022] Open
Abstract
The 5' N7-methylguanosine cap is a critical modification for mRNAs and many other RNAs in eukaryotic cells. Recent studies have uncovered an RNA 5' capping quality surveillance mechanism, with DXO/Rai1 decapping enzymes removing incomplete caps and enabling the degradation of the RNAs, in a process we also refer to as "no-cap decay." It has also been discovered recently that RNAs in eukaryotes, bacteria, and archaea can have noncanonical caps (NCCs), which are mostly derived from metabolites and cofactors such as NAD, FAD, dephospho-CoA, UDP-glucose, UDP-N-acetylglucosamine, and dinucleotide polyphosphates. These NCCs can affect RNA stability, mitochondrial functions, and possibly mRNA translation. The DXO/Rai1 enzymes and selected Nudix (nucleotide diphosphate linked to X) hydrolases have been shown to remove NCCs from RNAs through their deNADding, deFADding, deCoAping, and related activities, permitting the degradation of the RNAs. In this review, we summarize the recent discoveries made in this exciting new area of RNA biology.
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Affiliation(s)
- Selom K. Doamekpor
- Department of Biological Sciences, Columbia University, New York, New York, USA
| | - Sunny Sharma
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey, USA
| | - Megerditch Kiledjian
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey, USA.
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, New York, USA.
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Bollu A, Peters A, Rentmeister A. Chemo-Enzymatic Modification of the 5' Cap To Study mRNAs. Acc Chem Res 2022; 55:1249-1261. [PMID: 35420432 DOI: 10.1021/acs.accounts.2c00059] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The central dogma of molecular biology hinges on messenger RNA (mRNA), which presents a blueprint of the genetic information encoded in the DNA and serves as a template for translation into proteins. In addition to its fundamental importance in basic research, this class of biomolecules has recently become the first approved Covid vaccine, underscoring its utility in medical applications.Eukaryotic mRNA is heavily processed, including the 5' cap as the primary hallmark. This 5' cap protects mRNA from degradation by exoribonucleases but also interacts specifically with several proteins and enzymes to ensure mRNA turnover and processing, like splicing, export from the nucleus to the cytoplasm, and initiation of translation. The absence of a 5' cap leads to a strong immune response, and the methylation status contributes to distinguishing self from non-self RNA.Non-natural modifications of the 5' cap provide an avenue to label mRNAs and make them accessible to analyses, which is important to study their cellular localization, trafficking, and binding partners. They bear potential to engineer mRNAs, e.g., more stable or immunogenic mRNAs that are still translated, by impacting select interactions in a distinct manner. The modification of the 5' cap itself is powerful as it can be applied to make long mRNAs (∼1000 nt, not directly accessible by solid-phase synthesis) by in vitro transcription.This Account describes our contribution to the field of chemo-enzymatic modification of mRNA at the 5' cap. Our approach relies on RNA methyltransferases (MTases) with promiscuous activity on analogues of their natural cosubstrate S-adenosyl-L-methionine (AdoMet). We will describe how RNA MTases in combination with non-natural cosubstrates provide access to site-specific modification of different positions of the 5' cap, namely, the N2 and N7 position of guanosine and the N6 position of adenosine as the transcription start nucleotide (TSN) and exemplify strategies to make long mRNAs with modified 5' caps.We will compare the chemical and enzymatic synthesis of the AdoMet analogues used for this purpose. We could overcome previous limitations in methionine adenosyltransferase (MAT) substrate scope by engineering variants (termed PC-MATs) with the ability to convert methionine analogues with benzylic and photocaging groups at the sulfonium ion.The final part of this Account will highlight applications of the modified mRNAs. Like in many chemo-enzymatic approaches, a versatile strategy is to install small functional groups enzymatically and use them as handles in subsequent bioorthogonal reactions. We showed fluorescent labeling of mRNAs via different types of click chemistry in vitro and in cells. In a second line of applications, we used the handles to make mRNAs amenable for analyses, most notably next-generation sequencing. In the case of extremely promiscuous enzymes, the direct installation of photo-cross-linking groups was successful also and provided a way to covalently bind protein-interaction partners. Finally, the non-natural modifications of mRNAs can also modulate the properties of mRNAs. Propargylation of Am as the transcription start nucleotide at its N6 position maintained the translation of mRNAs but increased their immunogenicity. The installation of photocaging groups provides a way to revert these effects and control interactions by light.
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Affiliation(s)
- Amarnath Bollu
- Department of Chemistry and Pharmacy, Institute of Biochemistry Westfälische Wilhelms-Universität Münster, University of Münster, Corrensstrasse 36, 48149 Münster, Germany
| | - Aileen Peters
- Department of Chemistry and Pharmacy, Institute of Biochemistry Westfälische Wilhelms-Universität Münster, University of Münster, Corrensstrasse 36, 48149 Münster, Germany
| | - Andrea Rentmeister
- Department of Chemistry and Pharmacy, Institute of Biochemistry Westfälische Wilhelms-Universität Münster, University of Münster, Corrensstrasse 36, 48149 Münster, Germany
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50
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Vidya E, Duchaine TF. Eukaryotic mRNA Decapping Activation. Front Genet 2022; 13:832547. [PMID: 35401681 PMCID: PMC8984151 DOI: 10.3389/fgene.2022.832547] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/14/2022] [Indexed: 11/13/2022] Open
Abstract
The 5′-terminal cap is a fundamental determinant of eukaryotic gene expression which facilitates cap-dependent translation and protects mRNAs from exonucleolytic degradation. Enzyme-directed hydrolysis of the cap (decapping) decisively affects mRNA expression and turnover, and is a heavily regulated event. Following the identification of the decapping holoenzyme (Dcp1/2) over two decades ago, numerous studies revealed the complexity of decapping regulation across species and cell types. A conserved set of Dcp1/2-associated proteins, implicated in decapping activation and molecular scaffolding, were identified through genetic and molecular interaction studies, and yet their exact mechanisms of action are only emerging. In this review, we discuss the prevailing models on the roles and assembly of decapping co-factors, with considerations of conservation across species and comparison across physiological contexts. We next discuss the functional convergences of decapping machineries with other RNA-protein complexes in cytoplasmic P bodies and compare current views on their impact on mRNA stability and translation. Lastly, we review the current models of decapping activation and highlight important gaps in our current understanding.
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Affiliation(s)
- Elva Vidya
- Goodman Cancer Institute, McGill University, Montréal, QC, Canada
- Department of Biochemistry, McGill University, Montréal, QC, Canada
| | - Thomas F. Duchaine
- Goodman Cancer Institute, McGill University, Montréal, QC, Canada
- Department of Biochemistry, McGill University, Montréal, QC, Canada
- *Correspondence: Thomas F. Duchaine,
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