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Fisher AJ, Beal PA. Structural perspectives on adenosine to inosine RNA editing by ADARs. MOLECULAR THERAPY. NUCLEIC ACIDS 2024; 35:102284. [PMID: 39165563 PMCID: PMC11334849 DOI: 10.1016/j.omtn.2024.102284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/22/2024]
Abstract
Adenosine deaminases acting on RNA (ADARs) are enzymes that catalyze the hydrolytic deamination of adenosine to inosine. The editing feature of ADARs has garnered much attention as a therapeutic tool to repurpose ADARs to correct disease-causing mutations at the mRNA level in a technique called site-directed RNA editing (SDRE). Administering a short guide RNA oligonucleotide that hybridizes to a mutant sequence forms the requisite dsRNA substrate, directing ADARs to edit the desired adenosine. However, much is still unknown about ADARs' selectivity and sequence-specific effects on editing. Atomic-resolution structures can help provide additional insight to ADARs' selectivity and lead to novel guide RNA designs. Indeed, recent structures of ADAR domains have expanded our understanding on RNA binding and the base-flipping catalytic mechanism. These efforts have enabled the rational design of improved ADAR guide strands and advanced the therapeutic potential of the SDRE approach. While no full-length structure of any ADAR is known, this review presents an exposition of the structural basis for function of the different ADAR domains, focusing on human ADAR2. Key insights are extrapolated to human ADAR1, which is of substantial interest because of its widespread expression in most human tissues.
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Affiliation(s)
- Andrew J. Fisher
- Department of Chemistry, University of California, Davis, One Shields Ave, Davis, CA 95616, USA
- Department of Molecular and Cellular Biology, University of California, Davis, One Shields Ave, Davis, CA 95616, USA
| | - Peter A. Beal
- Department of Chemistry, University of California, Davis, One Shields Ave, Davis, CA 95616, USA
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2
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Wulff TF, Hahnke K, Lécrivain AL, Schmidt K, Ahmed-Begrich R, Finstermeier K, Charpentier E. Dynamics of diversified A-to-I editing in Streptococcus pyogenes is governed by changes in mRNA stability. Nucleic Acids Res 2024:gkae629. [PMID: 39087550 DOI: 10.1093/nar/gkae629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 07/01/2024] [Accepted: 07/23/2024] [Indexed: 08/02/2024] Open
Abstract
Adenosine-to-inosine (A-to-I) RNA editing plays an important role in the post-transcriptional regulation of eukaryotic cell physiology. However, our understanding of the occurrence, function and regulation of A-to-I editing in bacteria remains limited. Bacterial mRNA editing is catalysed by the deaminase TadA, which was originally described to modify a single tRNA in Escherichia coli. Intriguingly, several bacterial species appear to perform A-to-I editing on more than one tRNA. Here, we provide evidence that in the human pathogen Streptococcus pyogenes, tRNA editing has expanded to an additional tRNA substrate. Using RNA sequencing, we identified more than 27 editing sites in the transcriptome of S. pyogenes SF370 and demonstrate that the adaptation of S. pyogenes TadA to a second tRNA substrate has also diversified the sequence context and recoding scope of mRNA editing. Based on the observation that editing is dynamically regulated in response to several infection-relevant stimuli, such as oxidative stress, we further investigated the underlying determinants of editing dynamics and identified mRNA stability as a key modulator of A-to-I editing. Overall, our findings reveal the presence and diversification of A-to-I editing in S. pyogenes and provide novel insights into the plasticity of the editome and its regulation in bacteria.
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Affiliation(s)
- Thomas F Wulff
- Max Planck Unit for the Science of Pathogens, 10117 Berlin, Germany
| | - Karin Hahnke
- Max Planck Unit for the Science of Pathogens, 10117 Berlin, Germany
| | | | - Katja Schmidt
- Max Planck Unit for the Science of Pathogens, 10117 Berlin, Germany
| | | | | | - Emmanuelle Charpentier
- Max Planck Unit for the Science of Pathogens, 10117 Berlin, Germany
- Institute for Biology, Humboldt University Berlin, 10115 Berlin, Germany
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3
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Kawakami S, Johmura Y, Nakanishi M. Intracellular acidification and glycolysis modulate inflammatory pathway in senescent cells. J Biochem 2024; 176:97-108. [PMID: 38564227 PMCID: PMC11289320 DOI: 10.1093/jb/mvae032] [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: 03/01/2024] [Accepted: 03/05/2024] [Indexed: 04/04/2024] Open
Abstract
Senescent cells accumulate in various organs with ageing, and its accumulation induces chronic inflammation and age-related physiological dysfunctions. Several remodelling of intracellular environments have been identified in senescent cells, including enlargement of cell/nuclear size and intracellular acidification. Although these alterations of intracellular environments were reported to be involved in the unique characteristics of senescent cells, the contribution of intracellular acidification to senescence-associated cellular phenotypes is poorly understood. Here, we identified that the upregulation of TXNIP and its paralog ARRDC4 as a hallmark of intracellular acidification in addition to KGA-type GLS1. These genes were also upregulated in response to senescence-associated intracellular acidification. Neutralization of the intracellular acidic environment ameliorated not only senescence-related upregulation of TXNIP, ARRDC4 and KGA but also inflammation-related genes, possibly through suppression of PDK-dependent anaerobic glycolysis. Furthermore, we found that expression of the intracellular acidification-induced genes, TXNIP and ARRDC4, correlated with inflammatory gene expression in heterogeneous senescent cell population in vitro and even in vivo, implying that the contribution of intracellular pH to senescence-associated cellular features, such as SASP.
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Affiliation(s)
- Satoshi Kawakami
- Division of Cancer Cell Biology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
- Department of Biological Sciences, School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoshikazu Johmura
- Division of Cancer and Senescence Biology, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 Japan
| | - Makoto Nakanishi
- Division of Cancer Cell Biology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
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Jiao Y, Xu Y, Liu C, Miao R, Liu C, Wang Y, Liu J. The role of ADAR1 through and beyond its editing activity in cancer. Cell Commun Signal 2024; 22:42. [PMID: 38233935 PMCID: PMC10795376 DOI: 10.1186/s12964-023-01465-x] [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: 11/06/2023] [Accepted: 12/27/2023] [Indexed: 01/19/2024] Open
Abstract
Adenosine-to-inosine (A-to-I) editing of RNA, catalyzed by adenosine deaminase acting on RNA (ADAR) enzymes, is a prevalent RNA modification in mammals. It has been shown that A-to-I editing plays a critical role in multiple diseases, such as cardiovascular disease, neurological disorder, and particularly cancer. ADARs are the family of enzymes, including ADAR1, ADAR2, and ADAR3, that catalyze the occurrence of A-to-I editing. Notably, A-to-I editing is mainly catalyzed by ADAR1. Given the significance of A-to-I editing in disease development, it is important to unravel the complex roles of ADAR1 in cancer for the development of novel therapeutic interventions.In this review, we briefly describe the progress of research on A-to-I editing and ADARs in cancer, mainly focusing on the role of ADAR1 in cancer from both editing-dependent and independent perspectives. In addition, we also summarized the factors affecting the expression and editing activity of ADAR1 in cancer.
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Affiliation(s)
- Yue Jiao
- School of Basic Medicine Sciences, Weifang Medical University, Weifang, 261053, China
| | - Yuqin Xu
- School of Basic Medicine Sciences, Weifang Medical University, Weifang, 261053, China
| | - Chengbin Liu
- School of Basic Medicine Sciences, Weifang Medical University, Weifang, 261053, China
| | - Rui Miao
- School of Basic Medicine Sciences, Weifang Medical University, Weifang, 261053, China
| | - Chunyan Liu
- School of Basic Medicine Sciences, Weifang Medical University, Weifang, 261053, China
| | - Yilong Wang
- School of Basic Medicine Sciences, Weifang Medical University, Weifang, 261053, China
| | - Jiao Liu
- School of Basic Medicine Sciences, Weifang Medical University, Weifang, 261053, China.
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5
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Li W, Bu M, Hu R, Jiang S, Chen L, Somero GN. Tissue-specific temperature dependence of RNA editing levels in zebrafish. BMC Biol 2023; 21:262. [PMID: 37981664 PMCID: PMC10659053 DOI: 10.1186/s12915-023-01738-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 10/16/2023] [Indexed: 11/21/2023] Open
Abstract
BACKGROUND RNA editing by adenosine deaminase acting on RNA (ADAR) occurs in all metazoans and fulfils several functions. Here, we examined effects of acclimation temperature (27 °C, 18 °C,13 °C) on editing patterns in six tissues of zebrafish (Danio rerio). RESULTS Sites and total amounts of editing differed among tissues. Brain showed the highest levels, followed by gill and skin. In these highly edited tissues, decreases in temperatures led to large increases in total amounts of editing and changes in specific edited sites. Gene ontology analysis showed both similarities (e.g., endoplasmic reticulum stress response) and differences in editing among tissues. The majority of edited sites were in transcripts of transposable elements and the 3'UTR regions of protein coding genes. By experimental validation, translation efficiency was directly related to extent of editing of the 3'UTR region of an mRNA. CONCLUSIONS RNA editing increases 3'UTR polymorphism and affects efficiency of translation. Such editing may lead to temperature-adaptive changes in the proteome through altering relative amounts of synthesis of different proteins.
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Affiliation(s)
- Wenhao Li
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
- International Research Center for Marine Biosciences, Ministry of Science and Technology, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
| | - Mengdi Bu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
- International Research Center for Marine Biosciences, Ministry of Science and Technology, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
| | - Ruiqin Hu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
- International Research Center for Marine Biosciences, Ministry of Science and Technology, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
| | - Shouwen Jiang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
- International Research Center for Marine Biosciences, Ministry of Science and Technology, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China
| | - Liangbiao Chen
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China.
- International Research Center for Marine Biosciences, Ministry of Science and Technology, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, 201306, China.
| | - George N Somero
- Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, CA, 93950, USA.
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6
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Pfeiffer LS, Stafforst T. Precision RNA base editing with engineered and endogenous effectors. Nat Biotechnol 2023; 41:1526-1542. [PMID: 37735261 DOI: 10.1038/s41587-023-01927-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 07/26/2023] [Indexed: 09/23/2023]
Abstract
RNA base editing refers to the rewriting of genetic information within an intact RNA molecule and serves various functions, such as evasion of the endogenous immune system and regulation of protein function. To achieve this, certain enzymes have been discovered in human cells that catalyze the conversion of one nucleobase into another. This natural process could be exploited to manipulate and recode any base in a target transcript. In contrast to DNA base editing, analogous changes introduced in RNA are not permanent or inheritable but rather allow reversible and doseable effects that appeal to various therapeutic applications. The current practice of RNA base editing involves the deamination of adenosines and cytidines, which are converted to inosines and uridines, respectively. In this Review, we summarize current site-directed RNA base-editing strategies and highlight recent achievements to improve editing efficiency, precision, codon-targeting scope and in vivo delivery into disease-relevant tissues. Besides engineered editing effectors, we focus on strategies to harness endogenous adenosine deaminases acting on RNA (ADAR) enzymes and discuss limitations and future perspectives to apply the tools in basic research and as a therapeutic modality. We expect the field to realize the first RNA base-editing drug soon, likely on a well-defined genetic disease. However, the long-term challenge will be to carve out the sweet spot of the technology where its unique ability is exploited to modulate signaling cues, metabolism or other clinically relevant processes in a safe and doseable manner.
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Affiliation(s)
- Laura S Pfeiffer
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Thorsten Stafforst
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany.
- Gene and RNA Therapy Center, Faculty of Medicine, University of Tübingen, Tübingen, Germany.
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7
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Mendoza HG, Beal PA. Chemical Modifications in RNA: Elucidating the Chemistry of dsRNA-Specific Adenosine Deaminases (ADARs). Acc Chem Res 2023; 56:2489-2499. [PMID: 37665999 PMCID: PMC10826463 DOI: 10.1021/acs.accounts.3c00390] [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] [Indexed: 09/06/2023]
Abstract
The term RNA editing refers to any structural change in an RNA molecule (e.g. insertion, deletion, or base modification) that changes its coding properties and is not a result of splicing. An important class of enzymes involved in RNA editing is the ADAR family (adenosine deaminases acting on RNA), which facilitate the deamination of adenosine (A) to inosine (I) in double-stranded RNA (dsRNA). Inosines are decoded as guanosines (G) in most cellular processes; hence, A-to-I editing can be considered an A-to-G substitution. Among the RNA editing enzymes, ADARs are of particular interest because a large portion of RNA editing events are due to A-to-I editing by the two catalytically active human ADARs (ADAR1 and ADAR2). ADARs have diverse roles in RNA processing, gene expression regulation, and innate immunity; and mutations in the ADAR genes and dysregulated ADAR activity have been associated with cancer, autoimmune diseases, and neurological disorders. A-to-I editing is also currently being explored for correcting disease-causing mutations in the RNA, where therapeutic guide oligonucleotides complementary to the target transcript are used to form a dsRNA substrate and site-specifically direct ADAR editing. Knowledge of the mechanism of ADAR-catalyzed reaction and the origin of its substrate selectivity will allow understanding of ADAR’s role in disease biology and expedite the process of developing ADAR-targeted therapeutics. Chemically modified oligonucleotides provide a versatile platform for modulating the activity and interrogating the structure, function, and selectivity of nucleic acid binding or modifying proteins. In this account, we provide an overview of oligonucleotide modifications that have allowed us to gain deeper understanding of ADAR’s molecular mechanisms, which we utilize in the rational design and optimization of ADAR activity modulators. First, we describe the use of the nucleoside analog 8-azanebularine (8-azaN) to generate high-affinity ADAR-RNA complexes for biochemical and biophysical studies with ADARs, with particular emphasis on X-ray crystallography. We then discuss key observations derived from the crystal structures of ADAR bound to 8-azaN-modified RNA duplexes and describe how these findings provided insight into ADAR editing optimization by introducing nucleoside modifications at various positions in synthetic guide strands. We also present the informed design of 8-azaN-modified RNA duplexes that selectively bind and inhibit ADAR1 but not the closely-related ADAR2 enzyme. Finally, we conclude with some open questions on ADAR structure and substrate recognition and share our current endeavors in the development of ADAR guide oligonucleotides and inhibitors.
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Affiliation(s)
- Herra G. Mendoza
- Department of Chemistry, University of California, Davis, CA 95616 USA
| | - Peter A. Beal
- Department of Chemistry, University of California, Davis, CA 95616 USA
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8
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Tang Q, Li L, Wang Y, Wu P, Hou X, Ouyang J, Fan C, Li Z, Wang F, Guo C, Zhou M, Liao Q, Wang H, Xiang B, Jiang W, Li G, Zeng Z, Xiong W. RNA modifications in cancer. Br J Cancer 2023; 129:204-221. [PMID: 37095185 PMCID: PMC10338518 DOI: 10.1038/s41416-023-02275-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 03/30/2023] [Accepted: 04/06/2023] [Indexed: 04/26/2023] Open
Abstract
Currently, more than 170 modifications have been identified on RNA. Among these RNA modifications, various methylations account for two-thirds of total cases and exist on almost all RNAs. Roles of RNA modifications in cancer are garnering increasing interest. The research on m6A RNA methylation in cancer is in full swing at present. However, there are still many other popular RNA modifications involved in the regulation of gene expression post-transcriptionally besides m6A RNA methylation. In this review, we focus on several important RNA modifications including m1A, m5C, m7G, 2'-O-Me, Ψ and A-to-I editing in cancer, which will provide a new perspective on tumourigenesis by peeking into the complex regulatory network of epigenetic RNA modifications, transcript processing, and protein translation.
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Affiliation(s)
- Qiling Tang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Lvyuan Li
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Yumin Wang
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, 410078, Changsha, Hunan, China
| | - Pan Wu
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Xiangchan Hou
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Jiawei Ouyang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Chunmei Fan
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Zheng Li
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Fuyan Wang
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Can Guo
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Ming Zhou
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Qianjin Liao
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
| | - Hui Wang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
| | - Bo Xiang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Weihong Jiang
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, 410078, Changsha, Hunan, China
| | - Guiyuan Li
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Zhaoyang Zeng
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Wei Xiong
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China.
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China.
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9
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Booth BJ, Nourreddine S, Katrekar D, Savva Y, Bose D, Long TJ, Huss DJ, Mali P. RNA editing: Expanding the potential of RNA therapeutics. Mol Ther 2023; 31:1533-1549. [PMID: 36620962 PMCID: PMC9824937 DOI: 10.1016/j.ymthe.2023.01.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/06/2022] [Accepted: 01/04/2023] [Indexed: 01/09/2023] Open
Abstract
RNA therapeutics have had a tremendous impact on medicine, recently exemplified by the rapid development and deployment of mRNA vaccines to combat the COVID-19 pandemic. In addition, RNA-targeting drugs have been developed for diseases with significant unmet medical needs through selective mRNA knockdown or modulation of pre-mRNA splicing. Recently, RNA editing, particularly antisense RNA-guided adenosine deaminase acting on RNA (ADAR)-based programmable A-to-I editing, has emerged as a powerful tool to manipulate RNA to enable correction of disease-causing mutations and modulate gene expression and protein function. Beyond correcting pathogenic mutations, the technology is particularly well suited for therapeutic applications that require a transient pharmacodynamic effect, such as the treatment of acute pain, obesity, viral infection, and inflammation, where it would be undesirable to introduce permanent alterations to the genome. Furthermore, transient modulation of protein function, such as altering the active sites of enzymes or the interface of protein-protein interactions, opens the door to therapeutic avenues ranging from regenerative medicine to oncology. These emerging RNA-editing-based toolsets are poised to broadly impact biotechnology and therapeutic applications. Here, we review the emerging field of therapeutic RNA editing, highlight recent laboratory advancements, and discuss the key challenges on the path to clinical development.
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Affiliation(s)
| | - Sami Nourreddine
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | | | | | | | | | | | - Prashant Mali
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA.
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10
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Mendoza HG, Matos VJ, Park S, Pham KM, Beal PA. Selective Inhibition of ADAR1 Using 8-Azanebularine-Modified RNA Duplexes. Biochemistry 2023; 62:1376-1387. [PMID: 36972568 PMCID: PMC10804918 DOI: 10.1021/acs.biochem.2c00686] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Adenosine deaminases acting on RNA (ADARs) are RNA editing enzymes that catalyze the hydrolytic deamination of adenosine (A) to inosine (I) in dsRNA. In humans, two catalytically active ADARs, ADAR1 and ADAR2, perform this A-to-I editing event. The growing field of nucleotide base editing has highlighted ADARs as promising therapeutic agents while multiple studies have also identified ADAR1's role in cancer progression. However, the potential for site-directed RNA editing as well as the rational design of inhibitors is being hindered by the lack of detailed molecular understanding of RNA recognition by ADAR1. Here, we designed short RNA duplexes containing the nucleoside analog, 8-azanebularine (8-azaN), to gain insight into molecular recognition by the human ADAR1 catalytic domain. From gel shift and in vitro deamination experiments, we validate ADAR1 catalytic domain's duplex secondary structure requirement and present a minimum duplex length for binding (14 bp, with 5 bp 5' and 8 bp 3' to editing site). These findings concur with predicted RNA-binding contacts from a previous structural model of the ADAR1 catalytic domain. Finally, we establish that neither 8-azaN as a free nucleoside nor a ssRNA bearing 8-azaN inhibits ADAR1 and demonstrate that the 8-azaN-modified RNA duplexes selectively inhibit ADAR1 and not the closely related ADAR2 enzyme.
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Affiliation(s)
- Herra G. Mendoza
- Department of Chemistry, University of California, Davis, CA 95616 USA
| | | | - SeHee Park
- Department of Chemistry, University of California, Davis, CA 95616 USA
| | - Kevin M. Pham
- Department of Chemistry, University of California, Davis, CA 95616 USA
| | - Peter A. Beal
- Department of Chemistry, University of California, Davis, CA 95616 USA
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11
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Bahari Khasraghi L, Nouri M, Vazirzadeh M, Hashemipour N, Talebi M, Aghaei Zarch F, Majidpoor J, Kalhor K, Farnia P, Najafi S, Aghaei Zarch SM. MicroRNA-206 in human cancer: Mechanistic and clinical perspectives. Cell Signal 2023; 101:110525. [PMID: 36400383 DOI: 10.1016/j.cellsig.2022.110525] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 11/17/2022]
Abstract
MicroRNAs (miRNAs), small non-coding RNAs approximately 20-25 nt in length, play important roles via directly binding to the corresponding 3' UTR of target mRNAs. Recent research has shown that miRNAs cover a wide range of diseases, including several types of cancer. It is interesting to note that miR-206 operates as a tumor suppressor and is downregulated in abundant cancer types, such as breast cancer, lung cancer, colorectal cancer, and so forth. Interestingly, a growing number of studies have also reported that miR-206 could function as an oncogene and promote tumor cell proliferation. Thereby, miR-206 may act as either oncogenes or tumor suppressors under certain conditions. In addition, it was widely acknowledged that restoring tumor-suppressor miR-206 has emerged as an unconventional cancer therapy strategy. Therefore, miR-206 might be a newfangled procedure for achieving a more significant treatment outcome for cancer patients. This review summarizes the role of miR-206 in several cancer types and the contributions made between miR-206 and the diagnosis, treatment, and drug resistance of solid tumors.
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Affiliation(s)
- Leila Bahari Khasraghi
- 15 khordad Educational Hospital, Shahid Beheshti University of Medical Science, Tehran, Iran
| | - Morteza Nouri
- Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Masoud Vazirzadeh
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran
| | | | - Mehrdad Talebi
- Department of Medical Genetics, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | | | - Jamal Majidpoor
- Department of Anatomy, Faculty of Medicine, Infectious Disease Research Center, Gonabad University of Medical Sciences, Gonabad, Iran.
| | - Kambiz Kalhor
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, USA
| | - Poopak Farnia
- Mycobacteriology Research Centre, National Research Institute of Tuberculosis and Lung Disease, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Sajad Najafi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Seyed Mohsen Aghaei Zarch
- Department of Medical Genetics, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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12
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Li M, Yan C, Jiao Y, Xu Y, Bai C, Miao R, Jiang J, Liu J. Site-directed RNA editing by harnessing ADARs: advances and challenges. Funct Integr Genomics 2022; 22:1089-1103. [DOI: 10.1007/s10142-022-00910-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 10/12/2022] [Accepted: 10/17/2022] [Indexed: 11/04/2022]
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13
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Doherty EE, Karki A, Wilcox XE, Mendoza HG, Manjunath A, Matos VJ, Fisher AJ, Beal PA. ADAR activation by inducing a syn conformation at guanosine adjacent to an editing site. Nucleic Acids Res 2022; 50:10857-10868. [PMID: 36243986 PMCID: PMC9638939 DOI: 10.1093/nar/gkac897] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 09/27/2022] [Accepted: 10/03/2022] [Indexed: 11/27/2022] Open
Abstract
ADARs (adenosine deaminases acting on RNA) can be directed to sites in the transcriptome by complementary guide strands allowing for the correction of disease-causing mutations at the RNA level. However, ADARs show bias against editing adenosines with a guanosine 5′ nearest neighbor (5′-GA sites), limiting the scope of this approach. Earlier studies suggested this effect arises from a clash in the RNA minor groove involving the 2-amino group of the guanosine adjacent to an editing site. Here we show that nucleosides capable of pairing with guanosine in a syn conformation enhance editing for 5′-GA sites. We describe the crystal structure of a fragment of human ADAR2 bound to RNA bearing a G:G pair adjacent to an editing site. The two guanosines form a Gsyn:Ganti pair solving the steric problem by flipping the 2-amino group of the guanosine adjacent to the editing site into the major groove. Also, duplexes with 2′-deoxyadenosine and 3-deaza-2′-deoxyadenosine displayed increased editing efficiency, suggesting the formation of a Gsyn:AH+anti pair. This was supported by X-ray crystallography of an ADAR complex with RNA bearing a G:3-deaza dA pair. This study shows how non-Watson–Crick pairing in duplex RNA can facilitate ADAR editing enabling the design of next generation guide strands for therapeutic RNA editing.
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Affiliation(s)
- Erin E Doherty
- Department of Chemistry, University of California, Davis, CA, USA
| | - Agya Karki
- Department of Chemistry, University of California, Davis, CA, USA
| | - Xander E Wilcox
- Department of Chemistry, University of California, Davis, CA, USA
| | - Herra G Mendoza
- Department of Chemistry, University of California, Davis, CA, USA
| | | | | | - Andrew J Fisher
- Department of Chemistry, University of California, Davis, CA, USA.,Department of Molecular and Cellular Biology, University of California, Davis, CA, USA
| | - Peter A Beal
- Department of Chemistry, University of California, Davis, CA, USA
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14
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Dutta N, Deb I, Sarzynska J, Lahiri A. Inosine and its methyl derivatives: Occurrence, biogenesis, and function in RNA. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2022; 169-170:21-52. [PMID: 35065168 DOI: 10.1016/j.pbiomolbio.2022.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 12/11/2021] [Accepted: 01/11/2022] [Indexed: 05/21/2023]
Abstract
Inosine is one of the most common post-transcriptional modifications. Since its discovery, it has been noted for its ability to contribute to non-Watson-Crick interactions within RNA. Rapidly accumulating evidence points to the widespread generation of inosine through hydrolytic deamination of adenosine to inosine by different classes of adenosine deaminases. Three naturally occurring methyl derivatives of inosine, i.e., 1-methylinosine, 2'-O-methylinosine and 1,2'-O-dimethylinosine are currently reported in RNA modification databases. These modifications are expected to lead to changes in the structure, folding, dynamics, stability and functions of RNA. The importance of the modifications is indicated by the strong conservation of the modifying enzymes across organisms. The structure, binding and catalytic mechanism of the adenosine deaminases have been well-studied, but the underlying mechanism of the catalytic reaction is not very clear yet. Here we extensively review the existing data on the occurrence, biogenesis and functions of inosine and its methyl derivatives in RNA. We also included the structural and thermodynamic aspects of these modifications in our review to provide a detailed and integrated discussion on the consequences of A-to-I editing in RNA and the contribution of different structural and thermodynamic studies in understanding its role in RNA. We also highlight the importance of further studies for a better understanding of the mechanisms of the different classes of deamination reactions. Further investigation of the structural and thermodynamic consequences and functions of these modifications in RNA should provide more useful information about their role in different diseases.
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Affiliation(s)
- Nivedita Dutta
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata, 700009, West Bengal, India
| | - Indrajit Deb
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata, 700009, West Bengal, India
| | - Joanna Sarzynska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Ansuman Lahiri
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata, 700009, West Bengal, India.
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15
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Kotar A, Ma S, Keane SC. pH dependence of C•A, G•A and A•A mismatches in the stem of precursor microRNA-31. Biophys Chem 2022; 283:106763. [DOI: 10.1016/j.bpc.2022.106763] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/13/2022] [Accepted: 01/15/2022] [Indexed: 12/22/2022]
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16
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Tang Q, Rigby RE, Young GR, Hvidt AK, Davis T, Tan TK, Bridgeman A, Townsend AR, Kassiotis G, Rehwinkel J. Adenosine-to-inosine editing of endogenous Z-form RNA by the deaminase ADAR1 prevents spontaneous MAVS-dependent type I interferon responses. Immunity 2021; 54:1961-1975.e5. [PMID: 34525337 PMCID: PMC8459395 DOI: 10.1016/j.immuni.2021.08.011] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 05/13/2021] [Accepted: 08/11/2021] [Indexed: 01/05/2023]
Abstract
Nucleic acids are powerful triggers of innate immunity and can adopt the Z-conformation, an unusual left-handed double helix. Here, we studied the biological function(s) of Z-RNA recognition by the adenosine deaminase ADAR1, mutations in which cause Aicardi-Goutières syndrome. Adar1mZα/mZα mice, bearing two point mutations in the Z-nucleic acid binding (Zα) domain that abolish Z-RNA binding, displayed spontaneous induction of type I interferons (IFNs) in multiple organs, including in the lung, where both stromal and hematopoietic cells showed IFN-stimulated gene (ISG) induction. Lung neutrophils expressed ISGs induced by the transcription factor IRF3, indicating an initiating role for neutrophils in this IFN response. The IFN response in Adar1mZα/mZα mice required the adaptor MAVS, implicating cytosolic RNA sensing. Adenosine-to-inosine changes were enriched in transposable elements and revealed a specific requirement of ADAR1's Zα domain in editing of a subset of RNAs. Thus, endogenous RNAs in Z-conformation have immunostimulatory potential curtailed by ADAR1, with relevance to autoinflammatory disease in humans.
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Affiliation(s)
- Qiannan Tang
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Rachel E Rigby
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - George R Young
- Bioinformatics and Biostatistics STP, The Francis Crick Institute, London, NW1 1AT, UK
| | - Astrid Korning Hvidt
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Tanja Davis
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Tiong Kit Tan
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Anne Bridgeman
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Alain R Townsend
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK; Centre for Translational Immunology, Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford, OX3 7FZ, UK
| | - George Kassiotis
- Retroviral Immunology, The Francis Crick Institute, London, NW 1AT, UK; Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, W2 1NY, UK
| | - Jan Rehwinkel
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK.
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17
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Vesely C, Jantsch MF. An I for an A: Dynamic Regulation of Adenosine Deamination-Mediated RNA Editing. Genes (Basel) 2021; 12:1026. [PMID: 34356042 PMCID: PMC8304401 DOI: 10.3390/genes12071026] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 12/12/2022] Open
Abstract
RNA-editing by adenosine deaminases acting on RNA (ADARs) converts adenosines to inosines in structured RNAs. Inosines are read as guanosines by most cellular machineries. A to I editing has two major functions: first, marking endogenous RNAs as "self", therefore helping the innate immune system to distinguish repeat- and endogenous retrovirus-derived RNAs from invading pathogenic RNAs; and second, recoding the information of the coding RNAs, leading to the translation of proteins that differ from their genomically encoded versions. It is obvious that these two important biological functions of ADARs will differ during development, in different tissues, upon altered physiological conditions or after exposure to pathogens. Indeed, different levels of ADAR-mediated editing have been observed in different tissues, as a response to altered physiology or upon pathogen exposure. In this review, we describe the dynamics of A to I editing and summarize the known and likely mechanisms that will lead to global but also substrate-specific regulation of A to I editing.
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Affiliation(s)
| | - Michael F. Jantsch
- Division of Cell & Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090 Vienna, Austria;
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18
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Doherty EE, Wilcox XE, van Sint Fiet L, Kemmel C, Turunen JJ, Klein B, Tantillo DJ, Fisher AJ, Beal PA. Rational Design of RNA Editing Guide Strands: Cytidine Analogs at the Orphan Position. J Am Chem Soc 2021; 143:6865-6876. [PMID: 33939417 PMCID: PMC8608393 DOI: 10.1021/jacs.0c13319] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Adenosine Deaminases Acting on RNA (ADARs) convert adenosine to inosine in double stranded RNA. Human ADARs can be directed to predetermined target sites in the transcriptome by complementary guide strands, allowing for the correction of disease-causing mutations at the RNA level. Here we use structural information available for ADAR2-RNA complexes to guide the design of nucleoside analogs for the position in the guide strand that contacts a conserved glutamic acid residue in ADARs (E488 in human ADAR2), which flips the adenosine into the ADAR active site for deamination. Mutating this residue to glutamine (E488Q) results in higher activity because of the hydrogen bond donating ability of Q488 to N3 of the orphan cytidine on the guide strand. We describe the evaluation of cytidine analogs for this position that stabilize an activated conformation of the enzyme-RNA complex and increase catalytic rate for deamination by the wild-type enzyme. A new crystal structure of ADAR2 bound to duplex RNA bearing a cytidine analog revealed a close contact between E488, stabilized by an additional hydrogen bond and altered charge distribution when compared to cytidine. In human cells and mouse primary liver fibroblasts, this single nucleotide modification increased directed editing yields when compared to an otherwise identical guide oligonucleotide. Our results show that modification of the guide RNA can mimic the effect of hyperactive mutants and advance the approach of recruiting endogenous ADARs for site-directed RNA editing.
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Affiliation(s)
- Erin E Doherty
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Xander E Wilcox
- Department of Chemistry, University of California, Davis, California 95616, United States
| | | | | | | | - Bart Klein
- ProQR Therapeutics, 2333 CK Leiden, The Netherlands
| | - Dean J Tantillo
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Andrew J Fisher
- Department of Chemistry, University of California, Davis, California 95616, United States
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616, United States
| | - Peter A Beal
- Department of Chemistry, University of California, Davis, California 95616, United States
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19
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Garikipati VNS, Uchida S. Elucidating the Functions of Non-Coding RNAs from the Perspective of RNA Modifications. Noncoding RNA 2021; 7:ncrna7020031. [PMID: 34065036 PMCID: PMC8163165 DOI: 10.3390/ncrna7020031] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/29/2021] [Accepted: 05/05/2021] [Indexed: 12/11/2022] Open
Abstract
It is now commonly accepted that most of the mammalian genome is transcribed as RNA, yet less than 2% of such RNA encode for proteins. A majority of transcribed RNA exists as non-protein-coding RNAs (ncRNAs) with various functions. Because of the lack of sequence homologies among most ncRNAs species, it is difficult to infer the potential functions of ncRNAs by examining sequence patterns, such as catalytic domains, as in the case of proteins. Added to the existing complexity of predicting the functions of the ever-growing number of ncRNAs, increasing evidence suggests that various enzymes modify ncRNAs (e.g., ADARs, METTL3, and METTL14), which has opened up a new field of study called epitranscriptomics. Here, we examine the current status of ncRNA research from the perspective of epitranscriptomics.
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Affiliation(s)
- Venkata Naga Srikanth Garikipati
- Department of Emergency Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA;
- Dorothy M. Davis Heart Lung and Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Shizuka Uchida
- Center for RNA Medicine, Department of Clinical Medicine, Aalborg University, Frederikskaj 10B, 2. (building C), DK-2450 Copenhagen SV, Denmark
- Correspondence: or
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