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Bernal YA, Durán E, Solar I, Sagredo EA, Armisén R. ADAR-Mediated A>I(G) RNA Editing in the Genotoxic Drug Response of Breast Cancer. Int J Mol Sci 2024; 25:7424. [PMID: 39000531 PMCID: PMC11242177 DOI: 10.3390/ijms25137424] [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: 05/04/2024] [Revised: 06/13/2024] [Accepted: 06/24/2024] [Indexed: 07/16/2024] Open
Abstract
Epitranscriptomics is a field that delves into post-transcriptional changes. Among these modifications, the conversion of adenosine to inosine, traduced as guanosine (A>I(G)), is one of the known RNA-editing mechanisms, catalyzed by ADARs. This type of RNA editing is the most common type of editing in mammals and contributes to biological diversity. Disruption in the A>I(G) RNA-editing balance has been linked to diseases, including several types of cancer. Drug resistance in patients with cancer represents a significant public health concern, contributing to increased mortality rates resulting from therapy non-responsiveness and disease progression, representing the greatest challenge for researchers in this field. The A>I(G) RNA editing is involved in several mechanisms over the immunotherapy and genotoxic drug response and drug resistance. This review investigates the relationship between ADAR1 and specific A>I(G) RNA-edited sites, focusing particularly on breast cancer, and the impact of these sites on DNA damage repair and the immune response over anti-cancer therapy. We address the underlying mechanisms, bioinformatics, and in vitro strategies for the identification and validation of A>I(G) RNA-edited sites. We gathered databases related to A>I(G) RNA editing and cancer and discussed the potential clinical and research implications of understanding A>I(G) RNA-editing patterns. Understanding the intricate role of ADAR1-mediated A>I(G) RNA editing in breast cancer holds significant promise for the development of personalized treatment approaches tailored to individual patients' A>I(G) RNA-editing profiles.
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Affiliation(s)
- Yanara A Bernal
- Centro de Genética y Genómica, Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana Universidad del Desarrollo, Santiago 7610658, Chile
| | - Eduardo Durán
- Subdepartamento de Genómica y Genética Molecular, Sección Genética Humana, Instituto de Salud Pública de Chile, Avenida Marathon 1000, Ñuñoa, Santiago 7780050, Chile
| | - Isidora Solar
- Centro de Genética y Genómica, Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana Universidad del Desarrollo, Santiago 7610658, Chile
| | - Eduardo A Sagredo
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, SE-171 77 Stockholm, Sweden
- Science for Life Laboratory, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-171 77 Stockholm, Sweden
| | - Ricardo Armisén
- Centro de Genética y Genómica, Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana Universidad del Desarrollo, Santiago 7610658, Chile
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Hong X, Wei Z, He L, Bu Q, Wu G, Chen G, He W, Deng Q, Huang S, Huang Y, Yu C, Luo X, Lin Y. High-throughput virtual screening to identify potential small molecule inhibitors of the Zα domain of the adenosine deaminases acting on RNA 1(ADAR1). Eur J Pharm Sci 2024; 193:106672. [PMID: 38103658 DOI: 10.1016/j.ejps.2023.106672] [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: 06/25/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
Changes in RNA editing are closely associated with diseases such as cancer, viral infections, and autoimmune disorders. Adenosine deaminase (ADAR1), which acts on RNA 1, plays a key role in adenosine to inosine editing and is a potential therapeutic target for these various diseases. The p150 subtype of ADAR1 is the only one that contains a Zα domain that binds to both Z-DNA and Z-RNA. The Zα domain modulates immune responses and may be suitable targets for antiviral therapy and cancer immunotherapy. In this study, we attempted to utilize molecular docking to identify potential inhibitors that bind to the ADAR1 Zα domain. The virtual docking method screened the potential activity of more than 100,000 compounds on the Zα domain of ADAR1 and filtered to obtain the highest scoring results.We identified 71 compounds promising to bind to ADAR1 and confirmed that two of them, lithospermic acid and Regaloside B, interacts with the ADAR1 Zα domain by surface plasmonic resonance technique. The molecular dynamics calculation of the complex of lithospermic acid and ADAR1 also showed that the binding effect of lithospermic acid to ADAR1 was stable.This study provides a new perspective for the search of ADAR1 inhibitors, and further studies on the anti-ADAR11 activity of these compounds have broad prospects.
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Affiliation(s)
- Xiaoshan Hong
- Department of gynecology, Guangdong Women and Children Medical Hospital, Guangzhou 511400, China
| | - Zhifu Wei
- Department of gynecology, The Affiliated Shunde Hospital of Jinan University, Foshan 528300, China
| | - Lulu He
- Department of gynecology, Guangdong Women and Children Medical Hospital, Guangzhou 511400, China
| | - Qiaowen Bu
- Department of gynecology, Guangdong Women and Children Medical Hospital, Guangzhou 511400, China
| | - Guosong Wu
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou 510006, China
| | - Guanqiao Chen
- Department of gynecology, Guangdong Women and Children Medical Hospital, Guangzhou 511400, China
| | - Wanshan He
- Department of gynecology, Guangdong Women and Children Medical Hospital, Guangzhou 511400, China
| | - Qiuhua Deng
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou 510006, China
| | - Shiqi Huang
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou 510006, China
| | - Yongmei Huang
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou 510006, China.
| | - Cai Yu
- College of Pharmacy, Jinan University, Guangzhou 511436, China.
| | - Xiping Luo
- Department of gynecology, Guangdong Women and Children Medical Hospital, Guangzhou 511400, China.
| | - Yu Lin
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510006, China; Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou 510006, China.
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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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4
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Keegan LP, Hajji K, O’Connell MA. Adenosine Deaminase Acting on RNA (ADAR) Enzymes: A Journey from Weird to Wondrous. Acc Chem Res 2023; 56:3165-3174. [PMID: 37906879 PMCID: PMC10666284 DOI: 10.1021/acs.accounts.3c00433] [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: 07/27/2023] [Indexed: 11/02/2023]
Abstract
The adenosine deaminase acting on RNA (ADAR) enzymes that catalyze the conversion of adenosine to inosine in double-stranded (ds)RNA are evolutionarily conserved and are essential for many biological functions including nervous system function, hematopoiesis, and innate immunity. Initially it was assumed that the wide-ranging biological roles of ADARs are due to inosine in mRNA being read as guanosine by the translational machinery, allowing incomplete RNA editing in a target codon to generate two different proteins from the same primary transcript. In humans, there are approximately seventy-six positions that undergo site-specific editing in tissues at greater than 20% efficiency that result in recoding. Many of these transcripts are expressed in the central nervous system (CNS) and edited by ADAR2. Exploiting mouse genetic models revealed that transgenic mice lacking the gene encoding Adar2 die within 3 weeks of birth. Therefore, the role of ADAR2 in generating protein diversity in the nervous system is clear, but why is ADAR RNA editing activity essential in other biological processes, particularly editing mainly involving ADAR1? ADAR1 edits human transcripts having embedded Alu element inverted repeats (AluIRs), but the link from this activity to innate immunity activation was elusive. Mice lacking the gene encoding Adar1 are embryonically lethal, and a major breakthrough was the discovery that the role of Adar1 in innate immunity is due to its ability to edit such repetitive element inverted repeats which have the ability to form dsRNA in transcripts. The presence of inosine prevents activation of the dsRNA sensor melanoma differentiation-associated protein 5 (Mda5). Thus, inosine helps the cell discriminate self from non-self RNA, acting like a barcode on mRNA. As innate immunity is key to many different biological processes, the basis for this widespread biological role of the ADAR1 enzyme became evident.Our group has been studying ADARs from the outset of research on these enzymes. In this Account, we give a historical perspective, moving from the initial purification of ADAR1 and ADAR2 and cloning of their encoding genes up to the current research focus in the field and what questions still remain to be addressed. We discuss the characterizations of the proteins, their localizations, posttranslational modifications, and dimerization, and how all of these affect their biological activities. Another aspect we explore is the use of mouse and Drosophila genetic models to study ADAR functions and how these were crucial in determining the biological functions of the ADAR proteins. Finally, we describe the severe consequences of rare mutations found in the human genes encoding ADAR1 and ADAR2.
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Affiliation(s)
- Liam P. Keegan
- CEITEC, Masaryk
University, Kamenice 735/5, E35, Brno 62500, Czechia
| | - Khadija Hajji
- CEITEC, Masaryk
University, Kamenice 735/5, E35, Brno 62500, Czechia
| | - Mary A. O’Connell
- CEITEC, Masaryk
University, Kamenice 735/5, E35, Brno 62500, Czechia
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5
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Piazzi M, Bavelloni A, Salucci S, Faenza I, Blalock WL. Alternative Splicing, RNA Editing, and the Current Limits of Next Generation Sequencing. Genes (Basel) 2023; 14:1386. [PMID: 37510291 PMCID: PMC10379330 DOI: 10.3390/genes14071386] [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: 06/08/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/30/2023] Open
Abstract
The advent of next generation sequencing (NGS) has fostered a shift in basic analytic strategies of a gene expression analysis in diverse pathologies for the purposes of research, pharmacology, and personalized medicine. What was once highly focused research on individual signaling pathways or pathway members has, from the time of gene expression arrays, become a global analysis of gene expression that has aided in identifying novel pathway interactions, the discovery of new therapeutic targets, and the establishment of disease-associated profiles for assessing progression, stratification, or a therapeutic response. But there are significant caveats to this analysis that do not allow for the construction of the full picture. The lack of timely updates to publicly available databases and the "hit and miss" deposition of scientific data to these databases relegate a large amount of potentially important data to "garbage", begging the question, "how much are we really missing?" This brief perspective aims to highlight some of the limitations that RNA binding/modifying proteins and RNA processing impose on our current usage of NGS technologies as relating to cancer and how not fully appreciating the limitations of current NGS technology may negatively affect therapeutic strategies in the long run.
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Affiliation(s)
- Manuela Piazzi
- "Luigi Luca Cavalli-Sforza" Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), 40136 Bologna, Italy
- IRCCS, Istituto Ortopedico Rizzoli, 40136 Bologna, Italy
| | - Alberto Bavelloni
- Laboratorio di Oncologia Sperimentale, IRCCS, Istituto Ortopedico Rizzoli, 40136 Bologna, Italy
| | - Sara Salucci
- Dipartimento di Scienze Biomediche e Neuromotorie (DIBINEM), Università di Bologna, 40126 Bologna, Italy
| | - Irene Faenza
- Dipartimento di Scienze Biomediche e Neuromotorie (DIBINEM), Università di Bologna, 40126 Bologna, Italy
| | - William L Blalock
- "Luigi Luca Cavalli-Sforza" Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), 40136 Bologna, Italy
- IRCCS, Istituto Ortopedico Rizzoli, 40136 Bologna, Italy
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Cao Y, Huang C, Zhao X, Yu J. Regulation of SUMOylation on RNA metabolism in cancers. Front Mol Biosci 2023; 10:1137215. [PMID: 36911524 PMCID: PMC9998694 DOI: 10.3389/fmolb.2023.1137215] [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: 01/04/2023] [Accepted: 02/15/2023] [Indexed: 03/14/2023] Open
Abstract
Post-translational modifications of proteins play very important roles in regulating RNA metabolism and affect many biological pathways. Here we mainly summarize the crucial functions of small ubiquitin-like modifier (SUMO) modification in RNA metabolism including transcription, splicing, tailing, stability and modification, as well as its impact on the biogenesis and function of microRNA (miRNA) in particular. This review also highlights the current knowledge about SUMOylation regulation in RNA metabolism involved in many cellular processes such as cell proliferation and apoptosis, which is closely related to tumorigenesis and cancer progression.
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Affiliation(s)
- Yingting Cao
- Department of Biochemistry and Molecular Cell Biology and Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Caihu Huang
- Department of Biochemistry and Molecular Cell Biology and Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xian Zhao
- Department of Biochemistry and Molecular Cell Biology and Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jianxiu Yu
- Department of Biochemistry and Molecular Cell Biology and Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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7
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Bragado L, Magalnik M, Mammi P, Romero A, Gaioli N, Pozzi B, Srebrow A. SUMO conjugation regulates the activity of the Integrator complex. Nucleic Acids Res 2022; 50:12444-12461. [PMID: 36454007 PMCID: PMC9757034 DOI: 10.1093/nar/gkac1055] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 10/13/2022] [Accepted: 11/29/2022] [Indexed: 12/03/2022] Open
Abstract
RNA polymerase II (RNAPII) transcribes small nuclear RNA (snRNA) genes in close proximity to Cajal bodies, subnuclear compartments that depend on the SUMO isopeptidase USPL1 for their assembly. We show here that overexpression of USPL1 as well as of another nuclear SUMO isopeptidase, SENP6, alters snRNA 3'-end cleavage, a process carried out by the Integrator complex. Beyond its role in snRNA biogenesis, this complex is responsible for regulating the expression of different RNAPII transcripts. While several subunits of the complex are SUMO conjugation substrates, we found that the SUMOylation of the INTS11 subunit is regulated by USPL1 and SENP6. We defined Lys381, Lys462 and Lys475 as bona fide SUMO attachment sites on INTS11 and observed that SUMOylation of this protein modulates its subcellular localization and is required for Integrator activity. Moreover, while an INTS11 SUMOylation-deficient mutant is still capable of interacting with INTS4 and INTS9, its interaction with other subunits of the complex is affected. These findings point to a regulatory role for SUMO conjugation on Integrator activity and suggest the involvement of INTS11 SUMOylation in the assembly of the complex. Furthermore, this work adds Integrator-dependent RNA processing to the growing list of cellular processes regulated by SUMO conjugation.
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Affiliation(s)
- Laureano Bragado
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Melina Magalnik
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Pablo Mammi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Agustín Romero
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Nicolás Gaioli
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Berta Pozzi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
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Zhai J, Koh JH, Soong TW. RNA editing of ion channels and receptors in physiology and neurological disorders. OXFORD OPEN NEUROSCIENCE 2022; 1:kvac010. [PMID: 38596706 PMCID: PMC11003377 DOI: 10.1093/oons/kvac010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/14/2022] [Accepted: 05/15/2022] [Indexed: 04/11/2024]
Abstract
Adenosine-to-inosine (A-to-I) RNA editing is a post-transcriptional modification that diversifies protein functions by recoding RNA or alters protein quantity by regulating mRNA level. A-to-I editing is catalyzed by adenosine deaminases that act on RNA. Millions of editing sites have been reported, but they are mostly found in non-coding sequences. However, there are also several recoding editing sites in transcripts coding for ion channels or transporters that have been shown to play important roles in physiology and changes in editing level are associated with neurological diseases. These editing sites are not only found to be evolutionary conserved across species, but they are also dynamically regulated spatially, developmentally and by environmental factors. In this review, we discuss the current knowledge of A-to-I RNA editing of ion channels and receptors in the context of their roles in physiology and pathological disease. We also discuss the regulation of editing events and site-directed RNA editing approaches for functional study that offer a therapeutic pathway for clinical applications.
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Affiliation(s)
- Jing Zhai
- Department of Physiology, National University of Singapore, Singapore 117593, Singapore
| | - Joanne Huifen Koh
- Department of Physiology, National University of Singapore, Singapore 117593, Singapore
| | - Tuck Wah Soong
- Department of Physiology, National University of Singapore, Singapore 117593, Singapore
- Healthy Longevity Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore,
Singapore 117456, Singapore
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Koganti P, Kadali VN, Manikoth Ayyathan D, Emanuelli A, Paolini B, Levy-Cohen G, Blank M. The E3 ubiquitin ligase SMURF2 stabilizes RNA editase ADAR1p110 and promotes its adenosine-to-inosine (A-to-I) editing function. Cell Mol Life Sci 2022; 79:237. [PMID: 35403872 PMCID: PMC11072456 DOI: 10.1007/s00018-022-04272-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 03/17/2022] [Accepted: 03/23/2022] [Indexed: 11/03/2022]
Abstract
Epitranscriptomic changes in RNA catalyzed by the RNA-editing enzyme ADAR1 play an essential role in the regulation of diverse molecular and cellular processes, both under physiological conditions and in disease states, including cancer. Yet, despite a growing body of evidence pointing to ADAR1 as a potential therapeutic target, the mechanisms regulating its cellular abundance and activity, particularly of its constitutively expressed and ubiquitous form, ADAR1p110, are poorly understood. Here, we report the HECT-type E3 ubiquitin ligase SMURF2 as a pivotal regulator of ADAR1p110. We show that SMURF2, which is primarily known to promote the ubiquitin-mediated degradation of its protein substrates, protects ADAR1p110 from proteolysis and promotes its A-to-I editase activity in human and mouse cells and tissues. ADAR1p110's interactome analysis performed in human cells also showed a positive influence of SMURF2 on the stability and function of ADAR1p110. Mechanistically, we found that SMURF2 directly binds, ubiquitinates and stabilizes ADAR1p110 in an E3 ubiquitin ligase-dependent manner, through ADAR1p110 ubiquitination at lysine-744 (K744). Mutation of this residue to arginine (K744R), which is also associated with several human disorders, including dyschromatosis symmetrica hereditaria (DSH) and some types of cancer, abolished SMURF2-mediated protection of ADAR1p110 from both proteasomal and lysosomal degradation and inactivated ADAR1p110-mediated RNA editing. Our findings reveal a novel mechanism underlying the regulation of ADAR1 in mammalian cells and suggest SMURF2 as a key cellular factor influencing the protein abundance, interactions and functions of ADAR1p110.
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Affiliation(s)
- Praveen Koganti
- Laboratory of Molecular and Cellular Cancer Biology, Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
| | - Venkata Narasimha Kadali
- Laboratory of Molecular and Cellular Cancer Biology, Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
| | - Dhanoop Manikoth Ayyathan
- Laboratory of Molecular and Cellular Cancer Biology, Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
| | - Andrea Emanuelli
- Laboratory of Molecular and Cellular Cancer Biology, Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
| | - Biagio Paolini
- Department of Pathology and Laboratory Medicine, IRCCS Fondazione, Istituto Nazionale dei Tumori, Milan, Italy
| | - Gal Levy-Cohen
- Laboratory of Molecular and Cellular Cancer Biology, Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
| | - Michael Blank
- Laboratory of Molecular and Cellular Cancer Biology, Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel.
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10
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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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11
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Abstract
C6 deamination of adenosine (A) to inosine (I) in double-stranded RNA (dsRNA) is catalyzed by a family of enzymes known as ADARs (adenosine deaminases acting on RNA) encoded by three genes in mammals. Alternative promoters and splicing produce two ADAR1 proteins, an interferon-inducible cytoplasmic p150 and a constitutively expressed p110 that like ADAR2 is a nuclear enzyme. ADAR3 lacks deaminase activity. A-to-I editing occurs with both viral and cellular RNAs. Deamination activity is dependent on dsRNA substrate structure and regulatory RNA-binding proteins and ranges from highly site selective with hepatitis D RNA and glutamate receptor precursor messenger RNA (pre-mRNA) to hyperediting of measles virus and polyomavirus transcripts and cellular inverted Alu elements. Because I base-pairs as guanosine instead of A, editing can alter mRNA decoding, pre-mRNA splicing, and microRNA silencing. Editing also alters dsRNA structure, thereby suppressing innate immune responses including interferon production and action. Expected final online publication date for the Annual Review of Virology, Volume 8 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Christian K Pfaller
- Division of Veterinary Medicine, Paul-Ehrlich-Institute, Langen 63225, Germany
| | - Cyril X George
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, California 93106, USA;
| | - Charles E Samuel
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, California 93106, USA;
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12
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Lork M, Lieber G, Hale BG. Proteomic Approaches to Dissect Host SUMOylation during Innate Antiviral Immune Responses. Viruses 2021; 13:528. [PMID: 33806893 PMCID: PMC8004987 DOI: 10.3390/v13030528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/20/2021] [Accepted: 03/22/2021] [Indexed: 12/21/2022] Open
Abstract
SUMOylation is a highly dynamic ubiquitin-like post-translational modification that is essential for cells to respond to and resolve various genotoxic and proteotoxic stresses. Virus infections also constitute a considerable stress scenario for cells, and recent research has started to uncover the diverse roles of SUMOylation in regulating virus replication, not least by impacting antiviral defenses. Here, we review some of the key findings of this virus-host interplay, and discuss the increasingly important contribution that large-scale, unbiased, proteomic methodologies are making to discoveries in this field. We highlight the latest proteomic technologies that have been specifically developed to understand SUMOylation dynamics in response to cellular stresses, and comment on how these techniques might be best applied to dissect the biology of SUMOylation during innate immunity. Furthermore, we showcase a selection of studies that have already used SUMO proteomics to reveal novel aspects of host innate defense against viruses, such as functional cross-talk between SUMO proteins and other ubiquitin-like modifiers, viral antagonism of SUMO-modified antiviral restriction factors, and an infection-triggered SUMO-switch that releases endogenous retroelement RNAs to stimulate antiviral interferon responses. Future research in this area has the potential to provide new and diverse mechanistic insights into host immune defenses.
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Affiliation(s)
| | | | - Benjamin G. Hale
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland; (M.L.); (G.L.)
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13
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Schaefer MR. The Regulation of RNA Modification Systems: The Next Frontier in Epitranscriptomics? Genes (Basel) 2021; 12:genes12030345. [PMID: 33652758 PMCID: PMC7996938 DOI: 10.3390/genes12030345] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 12/12/2022] Open
Abstract
RNA modifications, long considered to be molecular curiosities embellishing just abundant and non-coding RNAs, have now moved into the focus of both academic and applied research. Dedicated research efforts (epitranscriptomics) aim at deciphering the underlying principles by determining RNA modification landscapes and investigating the molecular mechanisms that establish, interpret and modulate the information potential of RNA beyond the combination of four canonical nucleotides. This has resulted in mapping various epitranscriptomes at high resolution and in cataloguing the effects caused by aberrant RNA modification circuitry. While the scope of the obtained insights has been complex and exciting, most of current epitranscriptomics appears to be stuck in the process of producing data, with very few efforts to disentangle cause from consequence when studying a specific RNA modification system. This article discusses various knowledge gaps in this field with the aim to raise one specific question: how are the enzymes regulated that dynamically install and modify RNA modifications? Furthermore, various technologies will be highlighted whose development and use might allow identifying specific and context-dependent regulators of epitranscriptomic mechanisms. Given the complexity of individual epitranscriptomes, determining their regulatory principles will become crucially important, especially when aiming at modifying specific aspects of an epitranscriptome both for experimental and, potentially, therapeutic purposes.
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Affiliation(s)
- Matthias R Schaefer
- Centre for Anatomy & Cell Biology, Division of Cell-and Developmental Biology, Medical University of Vienna, Schwarzspanierstrasse 17, Haus C, 1st Floor, 1090 Vienna, Austria
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14
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Beknazarov N, Jin S, Poptsova M. Deep learning approach for predicting functional Z-DNA regions using omics data. Sci Rep 2020; 10:19134. [PMID: 33154517 PMCID: PMC7644757 DOI: 10.1038/s41598-020-76203-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 10/20/2020] [Indexed: 12/18/2022] Open
Abstract
Computational methods to predict Z-DNA regions are in high demand to understand the functional role of Z-DNA. The previous state-of-the-art method Z-Hunt is based on statistical mechanical and energy considerations about B- to Z-DNA transition using sequence information. Z-DNA CHiP-seq experiment results showed little overlap with Z-Hunt predictions implying that sequence information only is not sufficient to explain emergence of Z-DNA at different genomic locations. Adding epigenetic and other functional genomic mark-ups to DNA sequence level can help revealing the functional Z-DNA sites. Here we take advantage of the deep learning approach that can analyze and extract information from large volumes of molecular biology data. We developed a machine learning approach DeepZ that aggregates information from genome-wide maps of epigenetic markers, transcription factor and RNA polymerase binding sites, and chromosome accessibility maps. With the developed model we not only verify the experimental Z-DNA predictions, but also generate the whole-genome annotation, introducing new possible Z-DNA regions, which have not yet been found in experiments and can be of interest to the researchers from various fields.
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Affiliation(s)
- Nazar Beknazarov
- Laboratory of Bioinformatics, Faculty of Computer Science, National Research University Higher School of Economics, 11 Pokrovsky boulvar, Moscow, Russia, 101000
| | - Seungmin Jin
- Laboratory of Bioinformatics, Faculty of Computer Science, National Research University Higher School of Economics, 11 Pokrovsky boulvar, Moscow, Russia, 101000
| | - Maria Poptsova
- Laboratory of Bioinformatics, Faculty of Computer Science, National Research University Higher School of Economics, 11 Pokrovsky boulvar, Moscow, Russia, 101000.
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15
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Zarnack K, Balasubramanian S, Gantier MP, Kunetsky V, Kracht M, Schmitz ML, Sträßer K. Dynamic mRNP Remodeling in Response to Internal and External Stimuli. Biomolecules 2020; 10:biom10091310. [PMID: 32932892 PMCID: PMC7565591 DOI: 10.3390/biom10091310] [Citation(s) in RCA: 13] [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: 07/09/2020] [Revised: 09/02/2020] [Accepted: 09/08/2020] [Indexed: 02/06/2023] Open
Abstract
Signal transduction and the regulation of gene expression are fundamental processes in every cell. RNA-binding proteins (RBPs) play a key role in the post-transcriptional modulation of gene expression in response to both internal and external stimuli. However, how signaling pathways regulate the assembly of RBPs with mRNAs remains largely unknown. Here, we summarize observations showing that the formation and composition of messenger ribonucleoprotein particles (mRNPs) is dynamically remodeled in space and time by specific signaling cascades and the resulting post-translational modifications. The integration of signaling events with gene expression is key to the rapid adaptation of cells to environmental changes and stress. Only a combined approach analyzing the signal transduction pathways and the changes in post-transcriptional gene expression they cause will unravel the mechanisms coordinating these important cellular processes.
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Affiliation(s)
- Kathi Zarnack
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, 60438 Frankfurt a.M., Germany;
| | | | - Michael P. Gantier
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia;
- Department of Molecular and Translational Science, Monash University, Clayton, VIC 3800, Australia
| | - Vladislav Kunetsky
- Institute of Biochemistry, FB08, Justus Liebig University, 35392 Giessen, Germany;
| | - Michael Kracht
- Rudolf Buchheim Institute of Pharmacology, FB11, Justus Liebig University, 35392 Giessen, Germany;
| | - M. Lienhard Schmitz
- Institute of Biochemistry, FB11, Justus Liebig University, 35392 Giessen, Germany;
| | - Katja Sträßer
- Institute of Biochemistry, FB08, Justus Liebig University, 35392 Giessen, Germany;
- Correspondence:
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16
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Han J, An O, Hong H, Chan THM, Song Y, Shen H, Tang SJ, Lin JS, Ng VHE, Tay DJT, Molias FB, Pitcheshwar P, Tan HQ, Yang H, Chen L. Suppression of adenosine-to-inosine (A-to-I) RNA editome by death associated protein 3 (DAP3) promotes cancer progression. SCIENCE ADVANCES 2020; 6:eaba5136. [PMID: 32596459 PMCID: PMC7299630 DOI: 10.1126/sciadv.aba5136] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 05/06/2020] [Indexed: 05/02/2023]
Abstract
RNA editing introduces nucleotide changes in RNA sequences. Recent studies have reported that aberrant A-to-I RNA editing profiles are implicated in cancers. Albeit changes in expression and activity of ADAR genes are thought to have been responsible for the dysregulated RNA editome in diseases, they are not always correlated, indicating the involvement of secondary regulators. Here, we uncover DAP3 as a potent repressor of editing and a strong oncogene in cancer. DAP3 mainly interacts with the deaminase domain of ADAR2 and represses editing via disrupting association of ADAR2 with its target transcripts. PDZD7, an exemplary DAP3-repressed editing target, undergoes a protein recoding editing at stop codon [Stop →Trp (W)]. Because of editing suppression by DAP3, the unedited PDZD7WT, which is more tumorigenic than edited PDZD7Stop518W, is accumulated in tumors. In sum, cancer cells may acquire malignant properties for their survival advantage through suppressing RNA editome by DAP3.
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Affiliation(s)
- Jian Han
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Omer An
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - HuiQi Hong
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117549, Singapore
| | - Tim Hon Man Chan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Yangyang Song
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Haoqing Shen
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Sze Jing Tang
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Jaymie Siqi Lin
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Vanessa Hui En Ng
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Daryl Jin Tai Tay
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Fernando Bellido Molias
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Priyankaa Pitcheshwar
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Hui Qing Tan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117549, Singapore
| | - Henry Yang
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Leilei Chen
- Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117594, Singapore
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17
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Shi P, Guo Y, Su Y, Zhu M, Fu Y, Chi H, Wu J, Huang J. SUMOylation of DDX39A Alters Binding and Export of Antiviral Transcripts to Control Innate Immunity. THE JOURNAL OF IMMUNOLOGY 2020; 205:168-180. [DOI: 10.4049/jimmunol.2000053] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/21/2020] [Indexed: 12/22/2022]
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18
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Costa Cruz PH, Kato Y, Nakahama T, Shibuya T, Kawahara Y. A comparative analysis of ADAR mutant mice reveals site-specific regulation of RNA editing. RNA (NEW YORK, N.Y.) 2020; 26:454-469. [PMID: 31941663 PMCID: PMC7075269 DOI: 10.1261/rna.072728.119] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 01/09/2020] [Indexed: 05/03/2023]
Abstract
Adenosine-to-inosine RNA editing is an essential post-transcriptional modification catalyzed by adenosine deaminase acting on RNA (ADAR)1 and ADAR2 in mammals. For numerous sites in coding sequences (CDS) and microRNAs, editing is highly conserved and has significant biological consequences, for example, by altering amino acid residues and target recognition. However, no comprehensive and quantitative studies have been undertaken to determine how specific ADARs contribute to conserved sites in vivo. Here, we amplified each RNA region with editing site(s) separately and combined these for deep sequencing. Then, we compared the editing ratios of all sites that were conserved in CDS and microRNAs in the cerebral cortex and spleen of wild-type mice, Adar1E861A/E861AIfih-/- mice expressing inactive ADAR1 (Adar1 KI) and Adar2-/-Gria2R/R (Adar2 KO) mice. We found that most of the sites showed a preference for one ADAR. In contrast, some sites, such as miR-3099-3p, showed no ADAR preference. In addition, we found that the editing ratio for several sites, such as DACT3 R/G, was up-regulated in either Adar mutant mouse strain, whereas a coordinated interplay between ADAR1 and ADAR2 was required for the efficient editing of specific sites, such as the 5-HT2CR B site. We further created double mutant Adar1 KI Adar2 KO mice and observed viable and fertile animals with the complete absence of editing, demonstrating that ADAR1 and ADAR2 are the sole enzymes responsible for all editing sites in vivo. Collectively, these findings indicate that editing is regulated in a site-specific manner by the different interplay between ADAR1 and ADAR2.
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Affiliation(s)
- Pedro Henrique Costa Cruz
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yuki Kato
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Taisuke Nakahama
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Toshiharu Shibuya
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yukio Kawahara
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
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19
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Lundin E, Wu C, Widmark A, Behm M, Hjerling-Leffler J, Daniel C, Öhman M, Nilsson M. Spatiotemporal mapping of RNA editing in the developing mouse brain using in situ sequencing reveals regional and cell-type-specific regulation. BMC Biol 2020; 18:6. [PMID: 31937309 PMCID: PMC6961268 DOI: 10.1186/s12915-019-0736-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 12/23/2019] [Indexed: 01/01/2023] Open
Abstract
Background Adenosine-to-inosine (A-to-I) RNA editing is a process that contributes to the diversification of proteins that has been shown to be essential for neurotransmission and other neuronal functions. However, the spatiotemporal and diversification properties of RNA editing in the brain are largely unknown. Here, we applied in situ sequencing to distinguish between edited and unedited transcripts in distinct regions of the mouse brain at four developmental stages, and investigate the diversity of the RNA landscape. Results We analyzed RNA editing at codon-altering sites using in situ sequencing at single-cell resolution, in combination with the detection of individual ADAR enzymes and specific cell type marker transcripts. This approach revealed cell-type-specific regulation of RNA editing of a set of transcripts, and developmental and regional variation in editing levels for many of the targeted sites. We found increasing editing diversity throughout development, which arises through regional- and cell type-specific regulation of ADAR enzymes and target transcripts. Conclusions Our single-cell in situ sequencing method has proved useful to study the complex landscape of RNA editing and our results indicate that this complexity arises due to distinct mechanisms of regulating individual RNA editing sites, acting both regionally and in specific cell types. Electronic supplementary material The online version of this article (10.1186/s12915-019-0736-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elin Lundin
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, SE-171 21, Solna, Sweden.
| | - Chenglin Wu
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, SE-171 21, Solna, Sweden
| | - Albin Widmark
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 106 91, Stockholm, Sweden
| | - Mikaela Behm
- German Cancer Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Jens Hjerling-Leffler
- Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Chammiran Daniel
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 106 91, Stockholm, Sweden
| | - Marie Öhman
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 106 91, Stockholm, Sweden
| | - Mats Nilsson
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, SE-171 21, Solna, Sweden.
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20
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Nguéa P A, Robertson J, Herrera MC, Chymkowitch P, Enserink JM. Desumoylation of RNA polymerase III lies at the core of the Sumo stress response in yeast. J Biol Chem 2019; 294:18784-18795. [PMID: 31676685 DOI: 10.1074/jbc.ra119.009721] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/30/2019] [Indexed: 12/14/2022] Open
Abstract
Post-translational modification by small ubiquitin-like modifier (Sumo) regulates many cellular processes, including the adaptive response to various types of stress, referred to as the Sumo stress response (SSR). However, it remains unclear whether the SSR involves a common set of core proteins regardless of the type of stress or whether each particular type of stress induces a stress-specific SSR that targets a unique, largely nonoverlapping set of Sumo substrates. In this study, we used MS and a Gene Ontology approach to identify differentially sumoylated proteins during heat stress, hyperosmotic stress, oxidative stress, nitrogen starvation, and DNA alkylation in Saccharomyces cerevisiae cells. Our results indicate that each stress triggers a specific SSR signature centered on proteins involved in transcription, translation, and chromatin regulation. Strikingly, whereas the various stress-specific SSRs were largely nonoverlapping, all types of stress tested here resulted in desumoylation of subunits of RNA polymerase III, which correlated with a decrease in tRNA synthesis. We conclude that desumoylation and subsequent inhibition of RNA polymerase III constitutes the core of all stress-specific SSRs in yeast.
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Affiliation(s)
- Aurélie Nguéa P
- Department of Molecular Cell Biology, Institute for Cancer Research, Norwegian Radium Hospital, Montebello, N-0379 Oslo, Norway; Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, 0371 Oslo, Norway; Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Joseph Robertson
- Department of Molecular Cell Biology, Institute for Cancer Research, Norwegian Radium Hospital, Montebello, N-0379 Oslo, Norway; Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, 0371 Oslo, Norway
| | - Maria Carmen Herrera
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, 0371 Oslo, Norway; Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Pierre Chymkowitch
- Department of Microbiology, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway.
| | - Jorrit M Enserink
- Department of Molecular Cell Biology, Institute for Cancer Research, Norwegian Radium Hospital, Montebello, N-0379 Oslo, Norway; Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, 0371 Oslo, Norway; Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway.
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21
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Chen CY, Choong OK, Liu LW, Cheng YC, Li SC, Yen CYT, Wu MR, Chiang MH, Tsang TJ, Wu YW, Lin LC, Chen YL, Lin WC, Hacker TA, Kamp TJ, Hsieh PCH. MicroRNA let-7-TGFBR3 signalling regulates cardiomyocyte apoptosis after infarction. EBioMedicine 2019; 46:236-247. [PMID: 31401194 PMCID: PMC6712055 DOI: 10.1016/j.ebiom.2019.08.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/24/2019] [Accepted: 08/01/2019] [Indexed: 12/18/2022] Open
Abstract
Background Myocardial infarction (MI) is a life-threatening disease, often leading to heart failure. Defining therapeutic targets at an early time point is important to prevent heart failure. Methods MicroRNA screening was performed at early time points after MI using paired samples isolated from the infarcted and remote myocardium of pigs. We also examined the microRNA expression in plasma of MI patients and pigs. For mechanistic studies, AAV9-mediated microRNA knockdown and overexpression were administrated in mice undergoing MI. Findings MicroRNAs let-7a and let-7f were significantly downregulated in the infarct area within 24 h post-MI in pigs. We also observed a reduction of let-7a and let-7f in plasma of MI patients and pigs. Inhibition of let-7 exacerbated cardiomyocyte apoptosis, induced a cardiac hypertrophic phenotype, and resulted in worsened left ventricular ejection fraction. In contrast, ectopic let-7 overexpression significantly reduced those phenotypes and improved heart function. We then identified TGFBR3 as a target of let-7, and found that induction of Tgfbr3 in cardiomyocytes caused apoptosis, likely through p38 MAPK activation. Finally, we showed that the plasma TGFBR3 level was elevated after MI in plasma of MI patients and pigs. Interpretation Together, we conclude that the let-7-Tgfbr3-p38 MAPK signalling plays an important role in cardiomyocyte apoptosis after MI. Furthermore, microRNA let-7 and Tgfbr3 may serve as therapeutic targets and biomarkers for myocardial damage. Fund Ministry of Science and Technology, National Health Research Institutes, Academia Sinica Program for Translational Innovation of Biopharmaceutical Development-Technology Supporting Platform Axis, Thematic Research Program and the Summit Research Program, Taiwan.
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Affiliation(s)
- Chen-Yun Chen
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan
| | - Oi Kuan Choong
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan
| | - Li-Wei Liu
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan
| | - Yu-Che Cheng
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan
| | - Sung-Chou Li
- Genomics and Proteomics Core Laboratory, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | | | - Menq-Rong Wu
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan
| | - Ming-Hsien Chiang
- Institute of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Tien-Jui Tsang
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan
| | - Yen-Wen Wu
- Cardiology Division of Cardiovascular Medical Center and Department of Nuclear Medicine, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Lung-Chun Lin
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Yuh-Lien Chen
- Institute of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wen-Chang Lin
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan
| | - Timothy A Hacker
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Timothy J Kamp
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States; Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI, United States
| | - Patrick C H Hsieh
- Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan; Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States; Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI, United States; Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan; Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Division of Cardiovascular Surgery, Department of Surgery, National Taiwan University Hospital, Taipei 100, Taiwan.
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22
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Lamers MM, van den Hoogen BG, Haagmans BL. ADAR1: "Editor-in-Chief" of Cytoplasmic Innate Immunity. Front Immunol 2019; 10:1763. [PMID: 31404141 PMCID: PMC6669771 DOI: 10.3389/fimmu.2019.01763] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 07/11/2019] [Indexed: 12/12/2022] Open
Abstract
Specialized receptors that recognize molecular patterns such as double stranded RNA duplexes-indicative of viral replication-are potent triggers of the innate immune system. Although their activation is beneficial during viral infection, RNA transcribed from endogenous mobile genetic elements may also act as ligands potentially causing autoimmunity. Recent advances indicate that the adenosine deaminase ADAR1 through RNA editing is involved in dampening the canonical antiviral RIG-I-like receptor-, PKR-, and OAS-RNAse L pathways to prevent autoimmunity. However, this inhibitory effect must be overcome during viral infections. In this review we discuss ADAR1's critical role in balancing immune activation and self-tolerance.
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23
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Shanmugam R, Zhang F, Srinivasan H, Charles Richard JL, Liu KI, Zhang X, Woo CWA, Chua ZHM, Buschdorf JP, Meaney MJ, Tan MH. SRSF9 selectively represses ADAR2-mediated editing of brain-specific sites in primates. Nucleic Acids Res 2019; 46:7379-7395. [PMID: 29992293 PMCID: PMC6101530 DOI: 10.1093/nar/gky615] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 06/26/2018] [Indexed: 02/05/2023] Open
Abstract
Adenosine-to-inosine (A-to-I) RNA editing displays diverse spatial patterns across different tissues. However, the human genome encodes only two catalytically active editing enzymes (ADAR1 and ADAR2), suggesting that other regulatory factors help shape the editing landscape. Here, we show that the splicing factor SRSF9 selectively controls the editing of many brain-specific sites in primates. SRSF9 is more lowly expressed in the brain than in non-brain tissues. Gene perturbation experiments and minigene analysis of candidate sites demonstrated that SRSF9 could robustly repress A-to-I editing by ADAR2. We found that SRSF9 biochemically interacted with ADAR2 in the nucleus via its RRM2 domain. This interaction required the presence of the RNA substrate and disrupted the formation of ADAR2 dimers. Transcriptome-wide location analysis and RNA sequencing revealed 1328 editing sites that are controlled directly by SRSF9. This regulon is significantly enriched for brain-specific sites. We further uncovered a novel motif in the ADAR2-dependent SRSF9 binding sites and provided evidence that the splicing factor prevents loss of cell viability by inhibiting ADAR2-mediated editing of genes involved in proteostasis, energy metabolism, the cell cycle and DNA repair. Collectively, our results highlight the importance of SRSF9 as an editing regulator and suggest potential roles for other splicing factors.
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Affiliation(s)
- Raghuvaran Shanmugam
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore.,Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore
| | - Fan Zhang
- Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore
| | - Harini Srinivasan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore.,Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore
| | | | - Kaiwen I Liu
- Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore
| | - Xiujun Zhang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore.,Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore
| | - Cheok Wei A Woo
- Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore
| | - Zi Hao M Chua
- Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore.,School of Life Sciences and Chemical Technology, Ngee Ann Polytechnic, Singapore 599489, Singapore
| | - Jan Paul Buschdorf
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore 117609, Singapore
| | - Michael J Meaney
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore 117609, Singapore.,Douglas Mental Health University Institute, McGill University, Montreal (Quebec) H4H 1R3, Canada
| | - Meng How Tan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore.,Genome Institute of Singapore, Agency for Science Technology and Research, Singapore 138672, Singapore
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24
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Sinigaglia K, Wiatrek D, Khan A, Michalik D, Sambrani N, Sedmík J, Vukić D, O'Connell MA, Keegan LP. ADAR RNA editing in innate immune response phasing, in circadian clocks and in sleep. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:356-369. [DOI: 10.1016/j.bbagrm.2018.10.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 10/12/2018] [Accepted: 10/27/2018] [Indexed: 01/24/2023]
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25
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Quinones-Valdez G, Tran SS, Jun HI, Bahn JH, Yang EW, Zhan L, Brümmer A, Wei X, Van Nostrand EL, Pratt GA, Yeo GW, Graveley BR, Xiao X. Regulation of RNA editing by RNA-binding proteins in human cells. Commun Biol 2019; 2:19. [PMID: 30652130 PMCID: PMC6331435 DOI: 10.1038/s42003-018-0271-8] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 12/13/2018] [Indexed: 01/06/2023] Open
Abstract
Adenosine-to-inosine (A-to-I) editing, mediated by the ADAR enzymes, diversifies the transcriptome by altering RNA sequences. Recent studies reported global changes in RNA editing in disease and development. Such widespread editing variations necessitate an improved understanding of the regulatory mechanisms of RNA editing. Here, we study the roles of >200 RNA-binding proteins (RBPs) in mediating RNA editing in two human cell lines. Using RNA-sequencing and global protein-RNA binding data, we identify a number of RBPs as key regulators of A-to-I editing. These RBPs, such as TDP-43, DROSHA, NF45/90 and Ro60, mediate editing through various mechanisms including regulation of ADAR1 expression, interaction with ADAR1, and binding to Alu elements. We highlight that editing regulation by Ro60 is consistent with the global up-regulation of RNA editing in systemic lupus erythematosus. Additionally, most key editing regulators act in a cell type-specific manner. Together, our work provides insights for the regulatory mechanisms of RNA editing.
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Affiliation(s)
| | - Stephen S. Tran
- Bioinformatics Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Hyun-Ik Jun
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Jae Hoon Bahn
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Ei-Wen Yang
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Lijun Zhan
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, UConn Health, Farmington, CT 06030 USA
| | - Anneke Brümmer
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Xintao Wei
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, UConn Health, Farmington, CT 06030 USA
| | - Eric L. Van Nostrand
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093 USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, CA 92093 USA
| | - Gabriel A. Pratt
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093 USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, CA 92093 USA
- Bioinformatics and Systems Biology Graduate Program, University of California San Diego, La Jolla, CA 92093 USA
| | - Gene W. Yeo
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093 USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, CA 92093 USA
- Bioinformatics and Systems Biology Graduate Program, University of California San Diego, La Jolla, CA 92093 USA
| | - Brenton R. Graveley
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, UConn Health, Farmington, CT 06030 USA
| | - Xinshu Xiao
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA 90095 USA
- Bioinformatics Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095 USA
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA 90095 USA
- Molecular Biology Institute, University of California Los Angeles, Los Angeles, CA 90095 USA
- Institute for Quantitative and Computational Biology, University of California Los Angeles, Los Angeles, CA 90095 USA
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26
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Abstract
Noncoding RNAs (ncRNAs) have received much attention due to their central role in gene expression and translational regulation as well as due to their involvement in several biological processes and disease development. Small noncoding RNAs (sncRNAs), such as microRNAs and piwiRNAs, have been thoroughly investigated and functionally characterized. Long noncoding RNAs (lncRNAs), known to play an important role in chromatin-interacting transcription regulation, posttranscriptional regulation, cell-to-cell signaling, and protein regulation, are also being investigated to further elucidate their functional roles.Next-generation sequencing (NGS) technologies have greatly aided in characterizing the ncRNAome. Moreover, the coupling of NGS technology together with bioinformatics tools has been essential to the genome-wide detection of RNA modifications in ncRNAs. RNA editing, a common human co-transcriptional and posttranscriptional modification, is a dynamic biological phenomenon able to alter the sequence and the structure of primary transcripts (both coding and noncoding RNAs) during the maturation process, consequently influencing the biogenesis, as well as the function, of ncRNAs. In particular, the dysregulation of the RNA editing machineries have been associated with the onset of human diseases.In this chapter we discuss the potential functions of ncRNA editing and describe the knowledge base and bioinformatics resources available to investigate such phenomenon.
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27
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Pozzi B, Mammi P, Bragado L, Giono LE, Srebrow A. When SUMO met splicing. RNA Biol 2018; 15:689-695. [PMID: 29741121 PMCID: PMC6152442 DOI: 10.1080/15476286.2018.1457936] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 02/22/2018] [Accepted: 03/20/2018] [Indexed: 12/12/2022] Open
Abstract
Spliceosomal proteins have been revealed as SUMO conjugation targets. Moreover, we have reported that many of these are in a SUMO-conjugated form when bound to a pre-mRNA substrate during a splicing reaction. We demonstrated that SUMOylation of Prp3 (PRPF3), a component of the U4/U6 di-snRNP, is required for U4/U6•U5 tri-snRNP formation and/or recruitment to active spliceosomes. Expanding upon our previous results, we have shown that the splicing factor SRSF1 stimulates SUMO conjugation to several spliceosomal proteins. Given the relevance of the splicing process, as well as the complex and dynamic nature of its governing machinery, the spliceosome, the molecular mechanisms that modulate its function represent an attractive topic of research. We posit that SUMO conjugation could represent a way of modulating spliceosome assembly and thus, splicing efficiency. How cycles of SUMOylation/de-SUMOylation of spliceosomal proteins become integrated throughout the highly choreographed spliceosomal cycle awaits further investigation.
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Affiliation(s)
- Berta Pozzi
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE, UBA- CONICET); Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| | - Pablo Mammi
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE, UBA- CONICET); Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| | - Laureano Bragado
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE, UBA- CONICET); Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| | - Luciana E. Giono
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE, UBA- CONICET); Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| | - Anabella Srebrow
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE, UBA- CONICET); Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
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28
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Filippini A, Bonini D, Giacopuzzi E, La Via L, Gangemi F, Colombi M, Barbon A. Differential Enzymatic Activity of Rat ADAR2 Splicing Variants Is Due to Altered Capability to Interact with RNA in the Deaminase Domain. Genes (Basel) 2018; 9:genes9020079. [PMID: 29419780 PMCID: PMC5852575 DOI: 10.3390/genes9020079] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 01/19/2018] [Accepted: 01/19/2018] [Indexed: 12/17/2022] Open
Abstract
In mammals, adenosine (A) to inosine (I) RNA editing is performed by adenosine deaminases acting on RNA (ADAR), ADAR1 and ADAR2 enzymes, encoded by mRNAs that might undergo splicing process. In rat, two splicing events produce several isoforms of ADAR2, called ADAR2a, ADAR2b, ADAR2e, and ADAR2f, but only ADAR2a and ADAR2b are translated into an active protein. In particular, they differ for ten amino acids located in the catalytic domain of ADAR2b. Here, we focused on these two isoforms, analyzing the splicing pattern and their different function during rat neuronal maturation. We found an increase of editing levels in cortical neurons overexpressing ADAR2a compared to those overexpressing ADAR2b. These results indicate ADAR2a isoform as the most active one, as reported for the homologous human short variant. Furthermore, we showed that the differential editing activity is not due to a different dimerization of the two isoforms; it seems to be linked to the ten amino acids loop of ADAR2b that might interfere with RNA binding, occupying the space volume in which the RNA should be present in case of binding. These data might shed light on the complexity of ADAR2 regulations.
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Affiliation(s)
- Alice Filippini
- Division of Biology and Genetics-Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
| | - Daniela Bonini
- Division of Biology and Genetics-Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
| | - Edoardo Giacopuzzi
- Division of Biology and Genetics-Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
| | - Luca La Via
- Division of Biology and Genetics-Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
| | - Fabrizio Gangemi
- Division of Physics, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
| | - Marina Colombi
- Division of Biology and Genetics-Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
| | - Alessandro Barbon
- Division of Biology and Genetics-Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
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29
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Pozzi B, Bragado L, Will CL, Mammi P, Risso G, Urlaub H, Lührmann R, Srebrow A. SUMO conjugation to spliceosomal proteins is required for efficient pre-mRNA splicing. Nucleic Acids Res 2017; 45:6729-6745. [PMID: 28379520 PMCID: PMC5499870 DOI: 10.1093/nar/gkx213] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 03/24/2017] [Indexed: 12/26/2022] Open
Abstract
Pre-mRNA splicing is catalyzed by the spliceosome, a multi-megadalton ribonucleoprotein machine. Previous work from our laboratory revealed the splicing factor SRSF1 as a regulator of the SUMO pathway, leading us to explore a connection between this pathway and the splicing machinery. We show here that addition of a recombinant SUMO-protease decreases the efficiency of pre-mRNA splicing in vitro. By mass spectrometry analysis of anti-SUMO immunoprecipitated proteins obtained from purified splicing complexes formed along the splicing reaction, we identified spliceosome-associated SUMO substrates. After corroborating SUMOylation of Prp3 in cultured cells, we defined Lys 289 and Lys 559 as bona fide SUMO attachment sites within this spliceosomal protein. We further demonstrated that a Prp3 SUMOylation-deficient mutant while still capable of interacting with U4/U6 snRNP components, is unable to co-precipitate U2 and U5 snRNA and the spliceosomal proteins U2-SF3a120 and U5-Snu114. This SUMOylation-deficient mutant fails to restore the splicing of different pre-mRNAs to the levels achieved by the wild type protein, when transfected into Prp3-depleted cultured cells. This mutant also shows a diminished recruitment to active spliceosomes, compared to the wild type protein. These findings indicate that SUMO conjugation plays a role during the splicing process and suggest the involvement of Prp3 SUMOylation in U4/U6•U5 tri-snRNP formation and/or recruitment.
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Affiliation(s)
- Berta Pozzi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Laureano Bragado
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Cindy L Will
- Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Pablo Mammi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Guillermo Risso
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, MPI for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany.,Bioanalytics Group, Institute for Clinical Chemistry, University Medical Center Göttingen, Robert-Koch-Straße 40, D-37075 Göttingen, Germany
| | - Reinhard Lührmann
- Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Anabella Srebrow
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
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30
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Wang C, Zou J, Ma X, Wang E, Peng G. Mechanisms and implications of ADAR-mediated RNA editing in cancer. Cancer Lett 2017; 411:27-34. [PMID: 28974449 DOI: 10.1016/j.canlet.2017.09.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 09/20/2017] [Accepted: 09/21/2017] [Indexed: 12/11/2022]
Abstract
Adenosine deaminases acting on RNA (ADARs) are enzymes that catalyze the conversion of adenosine (A) to inosine (I) in double-stranded RNAs. Inosine exhibits similar properties as guanosine. As a result, A-to-I editing has a great impact on edited RNAs, not only affecting the base pairing properties, but also altering codons after translation. A-to-I editing are known to mediate and diversify transcripts. However, the overall biological effect of ADARs are still largely unknown. Aberrant ADAR activity and editing dysregulation are present in a variety of cancers, including hepatocellular carcinoma, chronic myelogenous leukemia, glioblastoma and melanoma. ADAR-mediated A-to-I editing can influence uncontrolled nucleotide changes, resulting in susceptibility of cells to developmental defects and potential carcinogenicity. A deeper understanding of the biological function of ADARs may provide mechanistic insights in the development of new cancer therapy. Here, we discuss recent advances in research on ADAR in detail including the structure and function of ADARs, the biochemistry of ADAR-mediated RNA editing, and the relevance of ADAR proteins in cancer.
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Affiliation(s)
- Chen Wang
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jun Zou
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xiangyi Ma
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Edward Wang
- OncoMed Pharmaceuticals, Redwood City, CA 94063, USA
| | - Guang Peng
- Department of Clinical Cancer Prevention, MD Anderson Cancer Center, The University of Texas, Houston, TX 77030, USA.
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31
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Chen YD, Liu JY, Lu YM, Zhu HT, Tang W, Wang QX, Lu HY. Functional roles of C/EBPα and SUMO‑modification in lung development. Int J Mol Med 2017; 40:1037-1046. [PMID: 28902364 PMCID: PMC5593452 DOI: 10.3892/ijmm.2017.3111] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 08/25/2017] [Indexed: 11/06/2022] Open
Abstract
CCAAT enhancer binding protein alpha (C/EBPα) is a transcription factor regulating the core aspects of cell growth and differentiation. The present study investigated the level and functional role of C/EBPα during the development of the rat lung. C/EBPα protein exhibits a dynamic expression pattern. The correlation between the expression of C/EBPα protein and the content of glycogen during lung maturation was analyzed to understand the function of C/EBPα in lung differentiation. The high expression of C/EBPα coincides with the reduction of glycogen in the fetal lung. In addition, the authors identified that changes in the level of C/EBPα are associated with the secretion of pulmonary surfactant. C/EBPα is modified by small ubiquitin-related modifier (SUMO) post-translationally. The results of double immunofluorescence staining and immunoprecipitation demonstrated that SUMO-modified C/EBPα was present in the lung. The sumoylated C/EBPα gradually decreased during lung differentiation and was negatively correlated with pulmonary surfactant secretion, thereby suggesting that the SUMO modification may participate in C/EBPα-mediated lung growth and differentiation. These results indicated that C/EBPα played a role in lung development and provided the insight into the mechanism underlying SUMO-modification.
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Affiliation(s)
- Yuan-Dong Chen
- Dean's Office, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Jiang-Yan Liu
- Department of Pediatrics, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Yan-Min Lu
- Department of Pediatrics, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Hai-Tao Zhu
- Department of Pediatrics, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Wei Tang
- Department of Pediatrics, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Qiu-Xia Wang
- Department of Pediatrics, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Hong-Yan Lu
- Department of Pediatrics, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
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32
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Abstract
Inosine is one of the most common modifications found in human RNAs and the Adenosine Deaminases that act on RNA (ADARs) are the main enzymes responsible for its production. ADARs were first discovered in the 1980s and since then our understanding of ADARs has advanced tremendously. For instance, it is now known that defective ADAR function can cause human diseases. Furthermore, recently solved crystal structures of the human ADAR2 deaminase bound to RNA have provided insights regarding the catalytic and substrate recognition mechanisms. In this chapter, we describe the occurrence of inosine in human RNAs and the newest perspective on the ADAR family of enzymes, including their substrate recognition, catalytic mechanism, regulation as well as the consequences of A-to-I editing, and their relation to human diseases.
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33
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Richard P, Vethantham V, Manley JL. Roles of Sumoylation in mRNA Processing and Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 963:15-33. [PMID: 28197904 DOI: 10.1007/978-3-319-50044-7_2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
SUMO has gained prominence as a regulator in a number of cellular processes. The roles of sumoylation in RNA metabolism, however, while considerable, remain less well understood. In this chapter we have assembled data from proteomic analyses, localization studies and key functional studies to extend SUMO's role to the area of mRNA processing and metabolism. Proteomic analyses have identified multiple putative sumoylation targets in complexes functioning in almost all aspects of mRNA metabolism, including capping, splicing and polyadenylation of mRNA precursors. Possible regulatory roles for SUMO have emerged in pre-mRNA 3' processing, where SUMO influences the functions of polyadenylation factors and activity of the entire complex. SUMO is also involved in regulating RNA editing and RNA binding by hnRNP proteins, and recent reports have suggested the involvement of the SUMO pathway in mRNA export. Together, these reports suggest that SUMO is involved in regulation of many aspects of mRNA metabolism and hold the promise for exciting future studies.
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Affiliation(s)
- Patricia Richard
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA
| | | | - James L Manley
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA.
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34
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Goldstein B, Agranat-Tamir L, Light D, Ben-Naim Zgayer O, Fishman A, Lamm AT. A-to-I RNA editing promotes developmental stage-specific gene and lncRNA expression. Genome Res 2016; 27:462-470. [PMID: 28031250 PMCID: PMC5340973 DOI: 10.1101/gr.211169.116] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 12/20/2016] [Indexed: 01/02/2023]
Abstract
A-to-I RNA editing is a conserved widespread phenomenon in which adenosine (A) is converted to inosine (I) by adenosine deaminases (ADARs) in double-stranded RNA regions, mainly noncoding. Mutations in ADAR enzymes in Caenorhabditis elegans cause defects in normal development but are not lethal as in human and mouse. Previous studies in C. elegans indicated competition between RNA interference (RNAi) and RNA editing mechanisms, based on the observation that worms that lack both mechanisms do not exhibit defects, in contrast to the developmental defects observed when only RNA editing is absent. To study the effects of RNA editing on gene expression and function, we established a novel screen that enabled us to identify thousands of RNA editing sites in nonrepetitive regions in the genome. These include dozens of genes that are edited at their 3′ UTR region. We found that these genes are mainly germline and neuronal genes, and that they are down-regulated in the absence of ADAR enzymes. Moreover, we discovered that almost half of these genes are edited in a developmental-specific manner, indicating that RNA editing is a highly regulated process. We found that many pseudogenes and other lncRNAs are also extensively down-regulated in the absence of ADARs in the embryo but not in the fourth larval (L4) stage. This down-regulation is not observed upon additional knockout of RNAi. Furthermore, levels of siRNAs aligned to pseudogenes in ADAR mutants are enhanced. Taken together, our results suggest a role for RNA editing in normal growth and development by regulating silencing via RNAi.
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Affiliation(s)
- Boaz Goldstein
- Faculty of Biology, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Lily Agranat-Tamir
- Faculty of Biology, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Dean Light
- Faculty of Biology, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Orna Ben-Naim Zgayer
- Faculty of Biology, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Alla Fishman
- Faculty of Biology, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Ayelet T Lamm
- Faculty of Biology, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
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35
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Kota V, Sommer G, Durette C, Thibault P, van Niekerk EA, Twiss JL, Heise T. SUMO-Modification of the La Protein Facilitates Binding to mRNA In Vitro and in Cells. PLoS One 2016; 11:e0156365. [PMID: 27224031 PMCID: PMC4880191 DOI: 10.1371/journal.pone.0156365] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 05/12/2016] [Indexed: 02/05/2023] Open
Abstract
The RNA-binding protein La is involved in several aspects of RNA metabolism including the translational regulation of mRNAs and processing of pre-tRNAs. Besides its well-described phosphorylation by Casein kinase 2, the La protein is also posttranslationally modified by the Small Ubiquitin-like MOdifier (SUMO), but the functional outcome of this modification has not been defined. The objective of this study was to test whether sumoylation changes the RNA-binding activity of La. Therefore, we established an in vitro sumoylation assay for recombinant human La and analyzed its RNA-binding activity by electrophoretic mobility shift assays. We identified two novel SUMO-acceptor sites within the La protein located between the RNA recognition motif 1 and 2 and we demonstrate for the first time that sumoylation facilitates the RNA-binding of La to small RNA oligonucleotides representing the oligopyrimidine tract (TOP) elements from the 5' untranslated regions (UTR) of mRNAs encoding ribosomal protein L22 and L37 and to a longer RNA element from the 5' UTR of cyclin D1 (CCND1) mRNA in vitro. Furthermore, we show by RNA immunoprecipitation experiments that a La mutant deficient in sumoylation has impaired RNA-binding activity in cells. These data suggest that modulating the RNA-binding activity of La by sumoylation has important consequences on its functionality.
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Affiliation(s)
- Venkatesh Kota
- Medical University of South Carolina, Department of Biochemistry & Molecular Biology, Charleston, South Carolina, United States of America
| | - Gunhild Sommer
- Medical University of South Carolina, Department of Biochemistry & Molecular Biology, Charleston, South Carolina, United States of America
| | - Chantal Durette
- Institute of Research in Immunology and Cancer University de Montreal, Station Centre-ville, Montreal, Canada
| | - Pierre Thibault
- Institute of Research in Immunology and Cancer University de Montreal, Station Centre-ville, Montreal, Canada
| | - Erna A. van Niekerk
- Department of Neurosciences-0626, University of California, San Diego, La Jolla, California, United States of America
| | - Jeffery L. Twiss
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina, United States of America
| | - Tilman Heise
- Medical University of South Carolina, Department of Biochemistry & Molecular Biology, Charleston, South Carolina, United States of America
- * E-mail:
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Washburn MC, Hundley HA. Trans and cis factors affecting A-to-I RNA editing efficiency of a noncoding editing target in C. elegans. RNA (NEW YORK, N.Y.) 2016; 22:722-728. [PMID: 26917557 PMCID: PMC4836646 DOI: 10.1261/rna.055079.115] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/28/2016] [Indexed: 05/30/2023]
Abstract
Adenosine-to-inosine RNA editing by ADARs affects thousands of adenosines in an organism's transcriptome. However, adenosines are not edited at equal levels nor do these editing levels correlate well with ADAR expression levels. Therefore, additional mechanisms are utilized by the cell to dictate the editing efficiency at a given adenosine. To examine cis-and trans-acting factors that regulate A-to-I editing levels specifically in neural cells, we utilized the model organism Caenorhabditis elegans We demonstrate that a double-stranded RNA (dsRNA) binding protein, ADR-1, inhibits editing in neurons, which is largely masked when examining editing levels from whole animals. Furthermore, expression of ADR-1 and mRNA expression of the editing target can act synergistically to regulate editing efficiency. In addition, we identify a dsRNA region within the Y75B8A.83' UTR that acts as acis-regulatory element by enhancing ADR-2 editing efficiency. Together, this work identifies mechanisms that regulate editing efficiency of noncoding A-to-I editing sites, which comprise the largest class of ADAR targets.
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Affiliation(s)
- Michael C Washburn
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
| | - Heather A Hundley
- Medical Sciences Program, Indiana University, Bloomington, Indiana 47405, USA
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Controlling the Editor: The Many Roles of RNA-Binding Proteins in Regulating A-to-I RNA Editing. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 907:189-213. [PMID: 27256387 DOI: 10.1007/978-3-319-29073-7_8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
RNA editing is a cellular process used to expand and diversify the RNA transcripts produced from a generally immutable genome. In animals, the most prevalent type of RNA editing is adenosine (A) to inosine (I) deamination catalyzed by the ADAR family. Throughout development, A-to-I editing levels increase while ADAR expression is constant, suggesting cellular mechanisms to regulate A-to-I editing exist. Furthermore, in several disease states, ADAR expression levels are similar to the normal state, but A-to-I editing levels are altered. Therefore, understanding how these enzymes are regulated in normal tissues and misregulated in disease states is of profound importance. This chapter will both discuss how to identify A-to-I editing sites across the transcriptome and explore the mechanisms that regulate ADAR editing activity, with particular focus on the diverse types of RNA-binding proteins implicated in regulating A-to-I editing in vivo.
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Post-Translational Modifications and RNA-Binding Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 907:297-317. [PMID: 27256391 DOI: 10.1007/978-3-319-29073-7_12] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
RNA-binding proteins affect cellular metabolic programs through development and in response to cellular stimuli. Though much work has been done to elucidate the roles of a handful of RNA-binding proteins and their effect on RNA metabolism, the progress of studies to understand the effects of post-translational modifications of this class of proteins is far from complete. This chapter summarizes the work that has been done to identify the consequence of post-translational modifications to some RNA-binding proteins. The effects of these modifications have been shown to increase the panoply of functions that a given RNA-binding protein can assume. We will survey the experimental methods that are used to identify the presence of several protein modifications and methods that attempt to discern the consequence of these modifications.
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Deger JM, Gerson JE, Kayed R. The interrelationship of proteasome impairment and oligomeric intermediates in neurodegeneration. Aging Cell 2015; 14:715-24. [PMID: 26053162 PMCID: PMC4568959 DOI: 10.1111/acel.12359] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/30/2015] [Indexed: 01/07/2023] Open
Abstract
Various neurodegenerative diseases are characterized by the accumulation of amyloidogenic proteins such as tau, α-synuclein, and amyloid-β. Prior to the formation of these stable aggregates, intermediate species of the respective proteins-oligomers-appear. Recently acquired data have shown that oligomers may be the most toxic and pathologically significant to neurodegenerative diseases such as Alzheimer's and Parkinson's. The covalent modification of these oligomers may be critically important for biological processes in disease. Ubiquitin and small ubiquitin-like modifiers are the commonly used tags for degradation. While the modification of large amyloid aggregates by ubiquitination is well established, very little is known about the role ubiquitin may play in oligomer processing and the importance of the more recently discovered sumoylation. Many proteins involved in neurodegeneration have been found to be sumoylated, notably tau protein in brains afflicted with Alzheimer's. This evidence suggests that while the cell may not have difficulty recognizing dangerous proteins, in brains afflicted with neurodegenerative disease, the proteasome may be unable to properly digest the tagged proteins. This would allow toxic aggregates to develop, leading to even more proteasome impairment in a snowball effect that could explain the exponential progression in most neurodegenerative diseases. A better understanding of the covalent modifications of oligomers could have a huge impact on the development of therapeutics for neurodegenerative diseases. This review will focus on the proteolysis of tau and other amyloidogenic proteins induced by covalent modification, and recent findings suggesting a relationship between tau oligomers and sumoylation.
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Affiliation(s)
- Jennifer M. Deger
- Departments of Neurology, Neuroscience and Cell Biology Mitchell Center for Neurodegenerative Diseases University of Texas Medical Branch 301 University Building, Medical Research Building Galveston TX 77555‐1045 USA
| | - Julia E. Gerson
- Departments of Neurology, Neuroscience and Cell Biology Mitchell Center for Neurodegenerative Diseases University of Texas Medical Branch 301 University Building, Medical Research Building Galveston TX 77555‐1045 USA
| | - Rakez Kayed
- Departments of Neurology, Neuroscience and Cell Biology Mitchell Center for Neurodegenerative Diseases University of Texas Medical Branch 301 University Building, Medical Research Building Galveston TX 77555‐1045 USA
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Tajaddod M, Jantsch MF, Licht K. The dynamic epitranscriptome: A to I editing modulates genetic information. Chromosoma 2015; 125:51-63. [PMID: 26148686 PMCID: PMC4761006 DOI: 10.1007/s00412-015-0526-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 06/22/2015] [Accepted: 06/24/2015] [Indexed: 02/03/2023]
Abstract
Adenosine to inosine editing (A to I editing) is a cotranscriptional process that contributes to transcriptome complexity by deamination of adenosines to inosines. Initially, the impact of A to I editing has been described for coding targets in the nervous system. Here, A to I editing leads to recoding and changes of single amino acids since inosine is normally interpreted as guanosine by cellular machines. However, more recently, new roles for A to I editing have emerged: Editing was shown to influence splicing and is found massively in Alu elements. Moreover, A to I editing is required to modulate innate immunity. We summarize the multiple ways in which A to I editing generates transcriptome variability and highlight recent findings in the field.
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Affiliation(s)
- Mansoureh Tajaddod
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Dr. Bohr Gasse 9/5, A-1030, Vienna, Austria
| | - Michael F Jantsch
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Dr. Bohr Gasse 9/5, A-1030, Vienna, Austria. .,Department of Cell Biology, Center of Cell Biology and Anatomy, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090, Vienna, Austria.
| | - Konstantin Licht
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Dr. Bohr Gasse 9/5, A-1030, Vienna, Austria.
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Abstract
Adenosine-to-inosine (A-to-I) RNA editing, the most prevalent mode of transcript modification in higher eukaryotes, is catalysed by the adenosine deaminases acting on RNA (ADARs). A-to-I editing imposes an additional layer of gene regulation as it dictates various aspects of RNA metabolism, including RNA folding, processing, localization and degradation. Furthermore, editing events in exonic regions contribute to proteome diversity as translational machinery decodes inosine as guanosine. Although it has been demonstrated that dysregulated A-to-I editing contributes to various diseases, the precise regulatory mechanisms governing this critical cellular process have yet to be fully elucidated. However, integration of previous studies revealed that regulation of A-to-I editing is multifaceted, weaving an intricate network of auto- and transregulations, including the involvement of virus-originated factors like adenovirus-associated RNA. Taken together, it is apparent that tipping of any regulatory components will have profound effects on A-to-I editing, which in turn contributes to both normal and aberrant physiological conditions. A complete understanding of this intricate regulatory network may ultimately be translated into new therapeutic strategies against diseases driven by perturbed RNA editing events. Herein, we review the current state of knowledge on the regulatory mechanisms governing A-to-I editing and propose the role of other co-factors that may be involved in this complex regulatory process. This review discusses the current state of knowledge on the mechanisms adopted in regulation of Adenosine-to-Inosine RNA editing.
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Abstract
miRNAs are important regulatory elements for gene expression that are involved in diverse physiologic and pathologic processes. Canonical miRNA biogenesis consists of a two-step processing, from primary transcripts (pri-miRNA) to precursor miRNAs (pre-miRNA) mediated by Drosha in the nucleus and from pre-miRNAs to mature miRNAs mediated by Dicer in the cytoplasm. Various routes of miRNA maturation that are tightly regulated by signaling cascades and specific to an individual or a subclass of miRNAs have been recently identified. Here, we review the current findings in signaling-mediated miRNA processing as well as their potential clinical relevance in cancer.
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Affiliation(s)
- Jia Shen
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas
| | - Mien-Chie Hung
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas. Center for Molecular Medicine and Graduate Institute of Cancer Biology, China Medical University, Taichung, Taiwan. Asia University, Taichung, Taiwan.
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Schweidenback CTH, Emerman AB, Jambhekar A, Blower MD. Evidence for multiple, distinct ADAR-containing complexes in Xenopus laevis. RNA (NEW YORK, N.Y.) 2015; 21:279-295. [PMID: 25519486 PMCID: PMC4338354 DOI: 10.1261/rna.047787.114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 11/20/2014] [Indexed: 06/04/2023]
Abstract
ADAR (adenosine deaminase acting on RNA) is an RNA-editing enzyme present in most metazoans that converts adenosines in double-stranded RNA targets into inosines. Although the RNA targets of ADAR-mediated editing have been extensively cataloged, our understanding of the cellular function of such editing remains incomplete. We report that long, double-stranded RNA added to Xenopus laevis egg extract is incorporated into an ADAR-containing complex whose protein components resemble those of stress granules. This complex localizes to microtubules, as assayed by accumulation on meiotic spindles. We observe that the length of a double-stranded RNA influences its incorporation into the microtubule-localized complex. ADAR forms a similar complex with endogenous RNA, but the endogenous complex fails to localize to microtubules. In addition, we characterize the endogenous, ADAR-associated RNAs and discover that they are enriched for transcripts encoding transcriptional regulators, zinc-finger proteins, and components of the secretory pathway. Interestingly, association with ADAR correlates with previously reported translational repression in early embryonic development. This work demonstrates that ADAR is a component of two, distinct ribonucleoprotein complexes that contain different types of RNAs and exhibit diverse cellular localization patterns. Our findings offer new insight into the potential cellular functions of ADAR.
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Affiliation(s)
- Caterina T H Schweidenback
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Amy B Emerman
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Ashwini Jambhekar
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Michael D Blower
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA
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Souquere S, Weil D, Pierron G. Comparative ultrastructure of CRM1-Nucleolar bodies (CNoBs), Intranucleolar bodies (INBs) and hybrid PML/p62 bodies uncovers new facets of nuclear body dynamic and diversity. Nucleus 2015; 6:326-38. [PMID: 26275159 PMCID: PMC4615761 DOI: 10.1080/19491034.2015.1082695] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 08/07/2015] [Accepted: 08/10/2015] [Indexed: 12/24/2022] Open
Abstract
In order to gain insights on the nuclear organization in mammalian cells, we characterized ultrastructurally nuclear bodies (NBs) previously described as fluorescent foci. Using high resolution immunoelectron microscopy (I-EM), we provide evidence that CNoBs (CRM1-Nucleolar bodies) and INBs (Intranucleolar bodies) are distinct genuine nucleolar structures in untreated HeLa cells. INBs are fibrillar and concentrate the post-translational modifiers SUMO1 and SUMO-2/3 as strongly as PML bodies. In contrast, the smallest CRM1-labeled CNoBs are vitreous, preferentially located at the periphery of the nucleolus and, intricately linked to the chromatin network. Upon blockage of the CRM1-dependent nuclear export by leptomycin B (LMB), CNoBs disappear while p62/SQSTM1-containing fibrillar nuclear bodies are induced. These p62 bodies are enriched in ubiquitinated proteins. They progressively associate with PML bodies to form hybrid bodies of which PML decorates the periphery while p62/SQSTM1 is centrally-located. Our study is expanding the repertoire of nuclear bodies; revealing a previously unrecognized composite nucleolar landscape and a new mode of interactions between ubiquitous (PML) and stress-induced (p62) nuclear bodies, resulting in the formation of hybrid bodies.
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Affiliation(s)
- Sylvie Souquere
- Functional Organization of the Cell; CNRS UMR-9196; Institut Gustave Roussy; Villejuif, France
| | - Dominique Weil
- UPMC Univ Paris 06; Institut de Biologie Paris-Seine (IBPS); CNRS UMR-7622; Paris, France
| | - Gérard Pierron
- Functional Organization of the Cell; CNRS UMR-9196; Institut Gustave Roussy; Villejuif, France
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Hood JL, Morabito MV, Martinez CR, Gilbert JA, Ferrick EA, Ayers GD, Chappell JD, Dermody TS, Emeson RB. Reovirus-mediated induction of ADAR1 (p150) minimally alters RNA editing patterns in discrete brain regions. Mol Cell Neurosci 2014; 61:97-109. [PMID: 24906008 PMCID: PMC4134954 DOI: 10.1016/j.mcn.2014.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 05/22/2014] [Accepted: 06/02/2014] [Indexed: 12/11/2022] Open
Abstract
Transcripts encoding ADAR1, a double-stranded, RNA-specific adenosine deaminase involved in the adenosine-to-inosine (A-to-I) editing of mammalian RNAs, can be alternatively spliced to produce an interferon-inducible protein isoform (p150) that is up-regulated in both cell culture and in vivo model systems in response to pathogen or interferon stimulation. In contrast to other tissues, p150 is expressed at extremely low levels in the brain and it is unclear what role, if any, this isoform may play in the innate immune response of the central nervous system (CNS) or whether the extent of editing for RNA substrates critical for CNS function is affected by its induction. To investigate the expression of ADAR1 isoforms in response to viral infection and subsequent alterations in A-to-I editing profiles for endogenous ADAR targets, we used a neurotropic strain of reovirus to infect neonatal mice and quantify A-to-I editing in discrete brain regions using a multiplexed, high-throughput sequencing strategy. While intracranial injection of reovirus resulted in a widespread increase in the expression of ADAR1 (p150) in multiple brain regions and peripheral organs, significant changes in site-specific A-to-I conversion were quite limited, suggesting that steady-state levels of p150 expression are not a primary determinant for modulating the extent of editing for numerous ADAR targets in vivo.
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Affiliation(s)
- Jennifer L Hood
- Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Michael V Morabito
- Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Charles R Martinez
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - James A Gilbert
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Elizabeth A Ferrick
- Department of Molecular Physiology & Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Gregory D Ayers
- Center for Quantitative Sciences, Vanderbilt University Medical Center, Nashville, TN, United States
| | - James D Chappell
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Terence S Dermody
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States; Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Ronald B Emeson
- Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, United States; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, United States; Department of Molecular Physiology & Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States.
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46
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Washburn MC, Kakaradov B, Sundararaman B, Wheeler E, Hoon S, Yeo GW, Hundley HA. The dsRBP and inactive editor ADR-1 utilizes dsRNA binding to regulate A-to-I RNA editing across the C. elegans transcriptome. Cell Rep 2014; 6:599-607. [PMID: 24508457 DOI: 10.1016/j.celrep.2014.01.011] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/19/2013] [Accepted: 01/09/2014] [Indexed: 12/18/2022] Open
Abstract
Inadequate adenosine-to-inosine editing of noncoding regions occurs in disease but is often uncorrelated with ADAR levels, underscoring the need to study deaminase-independent control of editing. C. elegans have two ADAR proteins, ADR-2 and the theoretically catalytically inactive ADR-1. Using high-throughput RNA sequencing of wild-type and adr mutant worms, we expand the repertoire of C. elegans edited transcripts over 5-fold and confirm that ADR-2 is the only active deaminase in vivo. Despite lacking deaminase function, ADR-1 affects editing of over 60 adenosines within the 3' UTRs of 16 different mRNAs. Furthermore, ADR-1 interacts directly with ADR-2 substrates, even in the absence of ADR-2, and mutations within its double-stranded RNA (dsRNA) binding domains abolish both binding and editing regulation. We conclude that ADR-1 acts as a major regulator of editing by binding ADR-2 substrates in vivo. These results raise the possibility that other dsRNA binding proteins, including the inactive human ADARs, regulate RNA editing through deaminase-independent mechanisms.
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Affiliation(s)
| | - Boyko Kakaradov
- Bioinformatics and Systems Biology Program, University of California, San Diego, La Jolla, CA 92093-0419, USA; Department of Cellular and Molecular Medicine, UCSD Stem Cell Program and Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093-0651, USA
| | - Balaji Sundararaman
- Department of Cellular and Molecular Medicine, UCSD Stem Cell Program and Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093-0651, USA
| | - Emily Wheeler
- Medical Sciences Program, Indiana University, Bloomington, IN 47405, USA
| | - Shawn Hoon
- Molecular Engineering Laboratory, A(∗)STAR, Singapore 138673, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore 639798, Singapore
| | - Gene W Yeo
- Bioinformatics and Systems Biology Program, University of California, San Diego, La Jolla, CA 92093-0419, USA; Department of Cellular and Molecular Medicine, UCSD Stem Cell Program and Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093-0651, USA; Molecular Engineering Laboratory, A(∗)STAR, Singapore 138673, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore.
| | - Heather A Hundley
- Medical Sciences Program, Indiana University, Bloomington, IN 47405, USA.
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ADAR enzyme and miRNA story: a nucleotide that can make the difference. Int J Mol Sci 2013; 14:22796-816. [PMID: 24256817 PMCID: PMC3856091 DOI: 10.3390/ijms141122796] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 11/04/2013] [Accepted: 11/05/2013] [Indexed: 12/21/2022] Open
Abstract
Adenosine deaminase acting on RNA (ADAR) enzymes convert adenosine (A) to inosine (I) in double-stranded (ds) RNAs. Since Inosine is read as Guanosine, the biological consequence of ADAR enzyme activity is an A/G conversion within RNA molecules. A-to-I editing events can occur on both coding and non-coding RNAs, including microRNAs (miRNAs), which are small regulatory RNAs of ~20–23 nucleotides that regulate several cell processes by annealing to target mRNAs and inhibiting their translation. Both miRNA precursors and mature miRNAs undergo A-to-I RNA editing, affecting the miRNA maturation process and activity. ADARs can also edit 3′ UTR of mRNAs, further increasing the interplay between mRNA targets and miRNAs. In this review, we provide a general overview of the ADAR enzymes and their mechanisms of action as well as miRNA processing and function. We then review the more recent findings about the impact of ADAR-mediated activity on the miRNA pathway in terms of biogenesis, target recognition, and gene expression regulation.
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48
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Hassan MA, Butty V, Jensen KDC, Saeij JPJ. The genetic basis for individual differences in mRNA splicing and APOBEC1 editing activity in murine macrophages. Genome Res 2013; 24:377-89. [PMID: 24249727 PMCID: PMC3941103 DOI: 10.1101/gr.166033.113] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Alternative splicing and mRNA editing are known to contribute to transcriptome diversity. Although alternative splicing is pervasive and contributes to a variety of pathologies, including cancer, the genetic context for individual differences in isoform usage is still evolving. Similarly, although mRNA editing is ubiquitous and associated with important biological processes such as intracellular viral replication and cancer development, individual variations in mRNA editing and the genetic transmissibility of mRNA editing are equivocal. Here, we have used linkage analysis to show that both mRNA editing and alternative splicing are regulated by the macrophage genetic background and environmental cues. We show that distinct loci, potentially harboring variable splice factors, regulate the splicing of multiple transcripts. Additionally, we show that individual genetic variability at the Apobec1 locus results in differential rates of C-to-U(T) editing in murine macrophages; with mouse strains expressing mostly a truncated alternative transcript isoform of Apobec1 exhibiting lower rates of editing. As a proof of concept, we have used linkage analysis to identify 36 high-confidence novel edited sites. These results provide a novel and complementary method that can be used to identify C-to-U editing sites in individuals segregating at specific loci and show that, beyond DNA sequence and structural changes, differential isoform usage and mRNA editing can contribute to intra-species genomic and phenotypic diversity.
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Affiliation(s)
- Musa A Hassan
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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49
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Garrett SC, Rosenthal JJC. A role for A-to-I RNA editing in temperature adaptation. Physiology (Bethesda) 2013; 27:362-9. [PMID: 23223630 DOI: 10.1152/physiol.00029.2012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
A-to-I RNA editing can recode mRNAs, giving organisms the option to express diverse, functionally distinct protein isoforms. Here, we propose that RNA editing is inherently geared for temperature adaptation because it tends to recode to smaller, less stabilizing amino acids. Studies on how editing affects protein function support this idea.
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Affiliation(s)
- Sandra C Garrett
- Institute of Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico.
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50
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Filosa G, Barabino SML, Bachi A. Proteomics strategies to identify SUMO targets and acceptor sites: a survey of RNA-binding proteins SUMOylation. Neuromolecular Med 2013; 15:661-76. [PMID: 23979992 DOI: 10.1007/s12017-013-8256-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 08/08/2013] [Indexed: 01/09/2023]
Abstract
SUMOylation is a protein posttranslational modification that participates in the regulation of numerous biological processes within the cells. Small ubiquitin-like modifier (SUMO) proteins are members of the ubiquitin-like protein family and, similarly to ubiquitin, are covalently linked to a lysine residue on a target protein via a multi-enzymatic cascade. To assess the specific mechanism triggered by SUMOylation, the identification of SUMO protein substrates and of the precise acceptor site to which SUMO is bound is of critical relevance. Despite hundreds of mammalian proteins have been described as targets of SUMOylation, the identification of the precise acceptor sites still represents an important analytical challenge because of the relatively low stoichiometry in vivo and the highly dynamic nature of this modification. Moreover, mass spectrometry-based identification of SUMOylated sites is hampered by the large peptide remnant of SUMO proteins that are left on the modified lysine residue upon tryptic digestion. The present review provides a survey of the strategies that have been exploited in order to enrich, purify and identify SUMOylation substrates and acceptor sites in human cells on a large-scale format. The success of the presented strategies helped to unravel the numerous activities of this modification, as it was shown by the exemplary case of the RNA-binding protein family, whose SUMOylation is here reviewed.
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Affiliation(s)
- Giuseppe Filosa
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
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