1
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Gupta K, Krieg E. Y-switch: a spring-loaded synthetic gene switch for robust DNA/RNA signal amplification and detection. Nucleic Acids Res 2024:gkae680. [PMID: 39149901 DOI: 10.1093/nar/gkae680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 07/04/2024] [Accepted: 07/31/2024] [Indexed: 08/17/2024] Open
Abstract
Nucleic acid tests (NATs) are essential for biomedical diagnostics. Traditional NATs, often complex and expensive, have prompted the exploration of toehold-mediated strand displacement (TMSD) circuits as an economical alternative. However, the wide application of TMSD-based reactions is limited by 'leakage'-the spurious activation of the reaction leading to high background signals and false positives. Here, we introduce the Y-Switch, a new TMSD cascade design that recognizes a custom nucleic acid input and generates an amplified output. The Y-Switch is based on a pair of thermodynamically spring-loaded DNA modules. The binding of a predefined nucleic acid target triggers an intermolecular reaction that activates a T7 promoter, leading to the perpetual transcription of a fluorescent aptamer that can be detected by a smartphone camera. The system is designed to permit the selective depletion of leakage byproducts to achieve high sensitivity and zero-background signal in the absence of the correct trigger. Using Zika virus (ZIKV)- and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-derived nucleic acid sequences, we show that the assay generates a reliable target-specific readout. Y-Switches detect native RNA under isothermal conditions without reverse transcription or pre-amplification, with a detection threshold as low as ∼200 attomole. The modularity of the assay allows easy re-programming for the detection of other targets by exchanging a single sequence domain. This work provides a low-complexity and high-fidelity synthetic biology tool for point-of-care diagnostics and for the construction of more complex biomolecular computations.
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Affiliation(s)
- Krishna Gupta
- Institute for Biofunctional Polymer Materials, Leibniz Institute of Polymer Research Dresden, Dresden, Germany
- Faculty of Chemistry and Food Chemistry, TU Dresden, Dresden, Germany
| | - Elisha Krieg
- Institute for Biofunctional Polymer Materials, Leibniz Institute of Polymer Research Dresden, Dresden, Germany
- Faculty of Chemistry and Food Chemistry, TU Dresden, Dresden, Germany
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2
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Najm R, Yavuz L, Jain R, El Naofal M, Ramaswamy S, Abuhammour W, Loney T, Nowotny N, Alsheikh-Ali A, Abou Tayoun A, Kandasamy RK. IFIH1 loss of function predisposes to inflammatory and SARS-CoV-2-related infectious diseases. Scand J Immunol 2024; 100:e13373. [PMID: 38757311 DOI: 10.1111/sji.13373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 04/03/2024] [Accepted: 04/29/2024] [Indexed: 05/18/2024]
Abstract
The IFIH1 gene, encoding melanoma differentiation-associated protein 5 (MDA5), is an indispensable innate immune regulator involved in the early detection of viral infections. Previous studies described MDA5 dysregulation in weakened immunological responses, and increased susceptibility to microbial infections and autoimmune disorders. Monoallelic gain-of-function of the IFIH1 gene has been associated with multisystem disorders, namely Aicardi-Goutieres and Singleton-Merten syndromes, while biallelic loss causes immunodeficiency. In this study, nine patients suffering from recurrent infections, inflammatory diseases, severe COVID-19 or multisystem inflammatory syndrome in children (MIS-C) were identified with putative loss-of-function IFIH1 variants by whole-exome sequencing. All patients revealed signs of lymphopaenia and an increase in inflammatory markers, including CRP, amyloid A, ferritin and IL-6. One patient with a pathogenic homozygous variant c.2807+1G>A was the most severe case showing immunodeficiency and glomerulonephritis. The c.1641+1G>C variant was identified in the heterozygous state in patients suffering from periodic fever, COVID-19 or MIS-C, while the c.2016delA variant was identified in two patients with inflammatory bowel disease or MIS-C. There was a significant association between IFIH1 monoallelic loss of function and susceptibility to infections in males. Expression analysis showed that PBMCs of one patient with a c.2016delA variant had a significant decrease in ISG15, IFNA and IFNG transcript levels, compared to normal PBMCs, upon stimulation with Poly(I:C), suggesting that MDA5 receptor truncation disrupts the immune response. Our findings accentuate the implication of rare monogenic IFIH1 loss-of-function variants in altering the immune response, and severely predisposing patients to inflammatory and infectious diseases, including SARS-CoV-2-related disorders.
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Affiliation(s)
- Rania Najm
- College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Health, Dubai, United Arab Emirates
| | - Lemis Yavuz
- Al Jalila Children's Hospital, Dubai, United Arab Emirates
| | - Ruchi Jain
- Al Jalila Genomics Center of Excellence, Al Jalila Children's Specialty Hospital, Dubai Health, Dubai, United Arab Emirates
| | - Maha El Naofal
- Al Jalila Genomics Center of Excellence, Al Jalila Children's Specialty Hospital, Dubai Health, Dubai, United Arab Emirates
| | - Sathishkumar Ramaswamy
- Al Jalila Genomics Center of Excellence, Al Jalila Children's Specialty Hospital, Dubai Health, Dubai, United Arab Emirates
| | | | - Tom Loney
- College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Health, Dubai, United Arab Emirates
| | - Norbert Nowotny
- College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Health, Dubai, United Arab Emirates
- Institute of Virology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Alawi Alsheikh-Ali
- College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Health, Dubai, United Arab Emirates
- Dubai Health, Dubai, United Arab Emirates
| | - Ahmad Abou Tayoun
- College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Health, Dubai, United Arab Emirates
- Al Jalila Genomics Center of Excellence, Al Jalila Children's Specialty Hospital, Dubai Health, Dubai, United Arab Emirates
| | - Richard K Kandasamy
- Departments of Laboratory Medicine and Pathology and Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota, USA
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Manipal Academy of Higher Education (MAHE), Manipal, India
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3
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Rehwinkel J, Mehdipour P. ADAR1: from basic mechanisms to inhibitors. Trends Cell Biol 2024:S0962-8924(24)00120-X. [PMID: 39030076 DOI: 10.1016/j.tcb.2024.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 06/17/2024] [Accepted: 06/20/2024] [Indexed: 07/21/2024]
Abstract
Adenosine deaminase acting on RNA 1 (ADAR1) converts adenosine to inosine in double-stranded RNA (dsRNA) molecules, a process known as A-to-I editing. ADAR1 deficiency in humans and mice results in profound inflammatory diseases characterised by the spontaneous induction of innate immunity. In cells lacking ADAR1, unedited RNAs activate RNA sensors. These include melanoma differentiation-associated gene 5 (MDA5) that induces the expression of cytokines, particularly type I interferons (IFNs), protein kinase R (PKR), oligoadenylate synthase (OAS), and Z-DNA/RNA binding protein 1 (ZBP1). Immunogenic RNAs 'defused' by ADAR1 may include transcripts from repetitive elements and other long duplex RNAs. Here, we review these recent fundamental discoveries and discuss implications for human diseases. Some tumours depend on ADAR1 to escape immune surveillance, opening the possibility of unleashing anticancer therapies with ADAR1 inhibitors.
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Affiliation(s)
- Jan Rehwinkel
- Medical Research Council Translational Immune Discovery Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK.
| | - Parinaz Mehdipour
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Headington, Oxford OX3 7DQ, UK.
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4
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Zhang H, Liu T, Liu X, You F, Yang J, Zhang N, Huang Y, Liang G. Histone deacetylase 8 promotes innate antiviral immunity through deacetylation of RIG-I. Front Cell Infect Microbiol 2024; 14:1415695. [PMID: 39035358 PMCID: PMC11257846 DOI: 10.3389/fcimb.2024.1415695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 06/25/2024] [Indexed: 07/23/2024] Open
Abstract
Histone deacetylates family proteins have been studied for their function in regulating viral replication by deacetylating non-histone proteins. RIG-I (Retinoic acid-inducible gene I) is a critical protein in RNA virus-induced innate antiviral signaling pathways. Our previous research showed that HDAC8 (histone deacetylase 8) involved in innate antiviral immune response, but the underlying mechanism during virus infection is still unclear. In this study, we showed that HDAC8 was involved in the regulation of vesicular stomatitis virus (VSV) replication. Over-expression of HDAC8 inhibited while knockdown promoted VSV replication. Further exploration demonstrated that HDAC8 interacted with and deacetylated RIG-I, which eventually lead to enhance innate antiviral immune response. Collectively, our data clearly demonstrated that HDAC8 inhibited VSV replication by promoting RIG-I mediated interferon production and downstream signaling pathway.
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Affiliation(s)
- Huijun Zhang
- Institute of Biomedical Research, Henan Academy Of Sciences, Zhengzhou, China
- School of Basic Medical and Forensic Medicine, Henan University of Science & Technology, Luoyang, China
| | - Tingli Liu
- Department of Medical Laboratory, Fenyang College of Shanxi Medical University, Fenyang, China
| | - Xinhua Liu
- Pharmacy Department, Luohe Hosptial Of Traditional Chinese Medicine, Luohe, China
| | - Fenfen You
- Institute of Biomedical Research, Henan Academy Of Sciences, Zhengzhou, China
| | - Jiaheng Yang
- Institute of Biomedical Research, Henan Academy Of Sciences, Zhengzhou, China
| | - Nan Zhang
- Institute of Biomedical Research, Henan Academy Of Sciences, Zhengzhou, China
| | - Ying Huang
- Institute of Biomedical Research, Henan Academy Of Sciences, Zhengzhou, China
| | - Gaofeng Liang
- Institute of Biomedical Research, Henan Academy Of Sciences, Zhengzhou, China
- School of Basic Medical and Forensic Medicine, Henan University of Science & Technology, Luoyang, China
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5
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Song W, Bian WJ, Li H, Guo QH, Wang J, Tang B, Zhang JY, Wei W, Liu XR, Liao WP, Li B, He N. IFIH1 variants are associated with generalised epilepsy preceded by febrile seizures. J Med Genet 2024:jmg-2024-109950. [PMID: 38964834 DOI: 10.1136/jmg-2024-109950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 06/17/2024] [Indexed: 07/06/2024]
Abstract
BACKGROUND IFIH1 variants have been reported to be associated with immune-related disorders with/without seizures. It is unknown whether IFIH1 variants are associated with common epilepsy without acquired causes and the mechanism underlying phenotypic variation remains elusive. METHODS Trio-based whole-exome sequencing was performed on patients with febrile seizures or epilepsy with antecedent febrile seizures. Previously reported variants were systematically reviewed to investigate genotype-phenotype associations. RESULTS Two de novo heterozygous and three biallelic missense variants were identified in five patients with generalised epilepsy with antecedent febrile seizures. The variants were predicted to be damaging by in silico tools and were associated with hydrogen bonding changes to neighbouring amino acids or decreased protein stability. Patients exhibited an early onset age and became seizure-free with favourable outcome. Further analysis revealed that de novo missense variants located in the Hel region resulted in seizures with multiple neurological abnormalities, while those in the pincer domain or C-terminal domain led to seizures with normal neurodevelopment, suggesting a sub-molecular effect. Biallelic missense variants, which were inherited from unaffected parents and presented low allele frequencies in general populations, were associated with seizures without neurological abnormalities. Truncation variants were related to refractory epilepsy and severe developmental delay, suggesting a genotype-phenotype correlation. IFIH1 is predominantly expressed in the neonatal stage and decreases dramatically in the adulthood, which is consistent with the early onset age and favourable outcome of the patients. CONCLUSIONS IFIH1 variants are potentially associated with generalised epilepsy with antecedent febrile seizures. The sub-molecular implication and genotype-phenotype association help explain phenotype variations of IFIH1 variants.
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Affiliation(s)
- Wang Song
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Wen-Jun Bian
- Department of Neurology, Guangdong Second Provincial General Hospital, Guangzhou, Guangdong, China
| | - Hua Li
- Department of Neurology, The Guangdong 999 Brain Hospital, Guangzhou, Guangdong, China
| | - Qing-Hui Guo
- Department of Pediatrics, The Second Hospital of Shandong University, Jinan, Shandong, China
| | - Jie Wang
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Bin Tang
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Jia-Yuan Zhang
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Wei Wei
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Xiao-Rong Liu
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Wei-Ping Liao
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Bin Li
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Na He
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China
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6
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Krenz B, Lee J, Kannan T, Eilers M. Immune evasion: An imperative and consequence of MYC deregulation. Mol Oncol 2024. [PMID: 38957016 DOI: 10.1002/1878-0261.13695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 05/08/2024] [Accepted: 06/19/2024] [Indexed: 07/04/2024] Open
Abstract
MYC has been implicated in the pathogenesis of a wide range of human tumors and has been described for many years as a transcription factor that regulates genes with pleiotropic functions to promote tumorigenic growth. However, despite extensive efforts to identify specific target genes of MYC that alone could be responsible for promoting tumorigenesis, the field is yet to reach a consensus whether this is the crucial function of MYC. Recent work shifts the view on MYC's function from being a gene-specific transcription factor to an essential stress resilience factor. In highly proliferating cells, MYC preserves cell integrity by promoting DNA repair at core promoters, protecting stalled replication forks, and/or preventing transcription-replication conflicts. Furthermore, an increasing body of evidence demonstrates that MYC not only promotes tumorigenesis by driving cell-autonomous growth, but also enables tumors to evade the host's immune system. In this review, we summarize our current understanding of how MYC impairs antitumor immunity and why this function is evolutionarily hard-wired to the biology of the MYC protein family. We show why the cell-autonomous and immune evasive functions of MYC are mutually dependent and discuss ways to target MYC proteins in cancer therapy.
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Affiliation(s)
- Bastian Krenz
- Department of Biochemistry and Molecular Biology, Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
- Mildred Scheel Early Career Center, Würzburg, Germany
| | - Jongkuen Lee
- Department of Biochemistry and Molecular Biology, Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Toshitha Kannan
- Department of Biochemistry and Molecular Biology, Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Martin Eilers
- Department of Biochemistry and Molecular Biology, Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, Würzburg, Germany
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7
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Li S, Deng X, Pathak D, Basavaraj R, Sun L, Cheng Y, Li JR, Burke M, Britz GW, Cheng C, Gao Y, Weng YL. Deficiency of m 6 A RNA methylation promotes ZBP1-mediated cell death. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.29.601251. [PMID: 38979320 PMCID: PMC11230363 DOI: 10.1101/2024.06.29.601251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
m 6 A RNA methylation suppresses the immunostimulatory potential of endogenous RNA. Deficiency of m 6 A provokes inflammatory responses and cell death, but the underlying mechanisms remain elusive. Here we showed that the noncoding RNA 7SK gains immunostimulatory potential upon m 6 A depletion and subsequently activates the RIG-I/MAVS axis to spark interferon (IFN) signaling cascades. Concomitant excess of IFN and m 6 A deficiency synergistically facilitate the formation of RNA G-quadruplexes (rG4) to promote ZBP1-mediated necroptotic cell death. Collectively, our findings delineate a hitherto uncharacterized mechanism that links m 6 A dysregulation with ZBP1 activity in triggering inflammatory cell death.
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8
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Bonhomme D, Poirier EZ. Early signaling pathways in virus-infected cells. Curr Opin Virol 2024; 66:101411. [PMID: 38718574 DOI: 10.1016/j.coviro.2024.101411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 04/05/2024] [Accepted: 04/10/2024] [Indexed: 06/07/2024]
Abstract
Virus infection activates specific pattern recognition receptors and immune signal transduction, resulting in pro-inflammatory cytokine production and activation of innate immunity. We describe here the molecular organization of early signaling pathways downstream of viral recognition, including conformational changes, post-translational modifications, formation of oligomers, and generation of small-molecule second messengers. Such molecular organization allows tight regulation of immune signal transduction, characterized by swift but transient responses, nonlinearity, and signal amplification. Pathologies of early immune signaling caused by genomic mutations illustrate the fine regulation of the immune transduction cascade.
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Affiliation(s)
- Delphine Bonhomme
- Institut Curie, Stem Cell Immunity Lab, PSL Research University, INSERM U932, Paris, France
| | - Enzo Z Poirier
- Institut Curie, Stem Cell Immunity Lab, PSL Research University, INSERM U932, Paris, France.
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9
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Hu SB, Li JB. RNA editing and immune control: from mechanism to therapy. Curr Opin Genet Dev 2024; 86:102195. [PMID: 38643591 PMCID: PMC11162905 DOI: 10.1016/j.gde.2024.102195] [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: 01/18/2024] [Revised: 04/02/2024] [Accepted: 04/02/2024] [Indexed: 04/23/2024]
Abstract
Adenosine-to-inosine RNA editing, catalyzed by the enzymes ADAR1 and ADAR2, stands as a pervasive RNA modification. A primary function of ADAR1-mediated RNA editing lies in labeling endogenous double-stranded RNAs (dsRNAs) as 'self', thereby averting their potential to activate innate immune responses. Recent findings have highlighted additional roles of ADAR1, independent of RNA editing, that are crucial for immune control. Here, we focus on recent progress in understanding ADAR1's RNA editing-dependent and -independent roles in immune control. We describe how ADAR1 regulates various dsRNA innate immune receptors through distinct mechanisms. Furthermore, we discuss the implications of ADAR1 and RNA editing in diseases, including autoimmune diseases and cancers.
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Affiliation(s)
- Shi-Bin Hu
- Department of Genetics, Stanford University, Stanford, CA 94305, USA.
| | - Jin Billy Li
- Department of Genetics, Stanford University, Stanford, CA 94305, USA.
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10
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Lee K, Ku J, Ku D, Kim Y. Inverted Alu repeats: friends or foes in the human transcriptome. Exp Mol Med 2024; 56:1250-1262. [PMID: 38871814 PMCID: PMC11263572 DOI: 10.1038/s12276-024-01177-3] [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: 10/09/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 06/15/2024] Open
Abstract
Alu elements are highly abundant primate-specific short interspersed nuclear elements that account for ~10% of the human genome. Due to their preferential location in gene-rich regions, especially in introns and 3' UTRs, Alu elements can exert regulatory effects on the expression of both host and neighboring genes. When two Alu elements with inverse orientations are positioned in close proximity, their transcription results in the generation of distinct double-stranded RNAs (dsRNAs), known as inverted Alu repeats (IRAlus). IRAlus are key immunogenic self-dsRNAs and post-transcriptional cis-regulatory elements that play a role in circular RNA biogenesis, as well as RNA transport and stability. Recently, IRAlus dsRNAs have emerged as regulators of transcription and activators of Z-DNA-binding proteins. The formation and activity of IRAlus can be modulated through RNA editing and interactions with RNA-binding proteins, and misregulation of IRAlus has been implicated in several immune-associated disorders. In this review, we summarize the emerging functions of IRAlus dsRNAs, the regulatory mechanisms governing IRAlus activity, and their relevance in the pathogenesis of human diseases.
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Affiliation(s)
- Keonyong Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Jayoung Ku
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Doyeong Ku
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Yoosik Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- Graduate School of Engineering Biology, KAIST, Daejeon, 34141, Republic of Korea.
- KAIST Institute for BioCentury (KIB), Daejeon, 34141, Republic of Korea.
- KAIST Institute for Health Science and Technology (KIHST), Daejeon, 34141, Republic of Korea.
- BioProcess Engineering Research Center and BioInformatics Research Center, KAIST, Daejeon, 34141, Republic of Korea.
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11
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Qin F, Cai B, Wang P, Cao R, Zhang Y, Wen H, Zheng Y, Zhao W, Gao C, Liu B. LTN1 promotes RLR degradation to inhibit immune response to RNA virus through the ESCRT pathway. Autophagy 2024; 20:1270-1285. [PMID: 38060409 PMCID: PMC11210911 DOI: 10.1080/15548627.2023.2291939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 11/30/2023] [Indexed: 06/22/2024] Open
Abstract
The excessive activation of immune responses will trigger autoimmune diseases or inflammatory injury. The endosomal sorting complexes required for transport (ESCRT) system can capture and mediate ubiquitinated protein degradation, which timely terminates signaling pathway hyperactivation. However, whether the ESCRT system participates in regulating RIGI-like receptor (RLR)-mediated antiviral responses remains unknown. In this study, we show that LTN1/listerin, a major component of RQC, can recruit E3 ubiquitin ligase TRIM27 to trigger K63-linked polyubiquitination of RIGI and IFIH1/MDA5. This K63-linked polyubiquitination facilitates the sorting and degradation of RIGI and IFIH1 proteins through the ESCRT-dependent pathway. Concordantly, LTN1 deficiency enhances the innate antiviral response to infection with RNA viruses. Thus, our work uncovers a new mechanism for RIGI and IFIH1 degradation and identifies the role of LTN1 in negatively regulating RLR-mediated antiviral innate immunity, which may provide new targets for the intervention of viral infection.Abbreviation: 5'-pppRNA: 5' triphosphate double stranded RNA; ATG5: autophagy related 5; ATG7: autophagy related 7; BafA1: bafilomycin A1; ESCRT: endosomal sorting complexes required for transport; CHX: cycloheximide; IFIH1/MDA5: interferon induced with helicase C domain 1; IFN: interferon; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; RIGI: RNA sensor RIG-I; RLR: RIGI-like receptors; RQC: ribosome-associated protein quality control; SeV: Sendai virus; TRIM27: tripartite motif-containing 27; VSV: vesicular stomatitis virus; VPS4: vacuolar protein sorting 4.
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Affiliation(s)
- Fei Qin
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Baoshan Cai
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Peng Wang
- Department of Clinical Laboratory, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Runyu Cao
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Yuling Zhang
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Hongling Wen
- Department of Microbiological Laboratory Technology, School of Public Health, Shandong University, Jinan, Shandong, China
| | - Yi Zheng
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Wei Zhao
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Pathogenic Biology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Chengjiang Gao
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Bingyu Liu
- Key Laboratory of Infection and Immunity of Shandong Province & Key Laboratory for Experimental Teratology of Ministry of Education, Shandong University, Jinan, Shandong, China
- Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
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12
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Huang E, Frydman C, Xiao X. Navigating the landscape of epitranscriptomics and host immunity. Genome Res 2024; 34:515-529. [PMID: 38702197 PMCID: PMC11146601 DOI: 10.1101/gr.278412.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2024]
Abstract
RNA modifications, also termed epitranscriptomic marks, encompass chemical alterations to individual nucleotides, including processes such as methylation and editing. These marks contribute to a wide range of biological processes, many of which are related to host immune system defense. The functions of immune-related RNA modifications can be categorized into three main groups: regulation of immunogenic RNAs, control of genes involved in innate immune response, and facilitation of adaptive immunity. Here, we provide an overview of recent research findings that elucidate the contributions of RNA modifications to each of these processes. We also discuss relevant methods for genome-wide identification of RNA modifications and their immunogenic substrates. Finally, we highlight recent advances in cancer immunotherapies that aim to reduce cancer cell viability by targeting the enzymes responsible for RNA modifications. Our presentation of these dynamic research avenues sets the stage for future investigations in this field.
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Affiliation(s)
- Elaine Huang
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, California 90095, USA
| | - Clara Frydman
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, California 90095, USA
| | - Xinshu Xiao
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, California 90095, USA;
- Department of Integrative Biology and Physiology, University of California, Los Angeles, California 90095, USA
- Molecular Biology Interdepartmental Program, University of California, Los Angeles, California 90095, USA
- Molecular Biology Institute, University of California, Los Angeles, California 90095, USA
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13
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Dorrity TJ, Shin H, Gertie JA, Chung H. The Sixth Sense: Self-nucleic acid sensing in the brain. Adv Immunol 2024; 161:53-83. [PMID: 38763702 PMCID: PMC11186578 DOI: 10.1016/bs.ai.2024.03.001] [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] [Indexed: 05/21/2024]
Abstract
Our innate immune system uses pattern recognition receptors (PRRs) as a first line of defense to detect microbial ligands and initiate an immune response. Viral nucleic acids are key ligands for the activation of many PRRs and the induction of downstream inflammatory and antiviral effects. Initially it was thought that endogenous (self) nucleic acids rarely activated these PRRs, however emerging evidence indicates that endogenous nucleic acids are able to activate host PRRs in homeostasis and disease. In fact, many regulatory mechanisms are in place to finely control and regulate sensing of self-nucleic acids by PRRs. Sensing of self-nucleic acids is particularly important in the brain, as perturbations to nucleic acid sensing commonly leads to neuropathology. This review will highlight the role of nucleic acid sensors in the brain, both in disease and homeostasis. We also indicate the source of endogenous stimulatory nucleic acids where known and summarize future directions for the study of this growing field.
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Key Words
- Brain
- DNA sensing PRRs: cGAS, AIM2, TLR9
- Neurodegeneration: Aicardi-Goutieres syndrome (AGS), Alzheimer's disease, Amyotrophic lateral sclerosis, Stroke, Traumatic brain injury
- Neurodevelopment
- Neuroinflammation
- Nuecleic acid immunity
- Pattern recognition receptors (PRRs)
- RNA sensing PRRs: MDA5, RIG-I, PKR, TLR3, TLR7/8
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Affiliation(s)
- Tyler J Dorrity
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States
| | - Heegwon Shin
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States
| | - Jake A Gertie
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States; Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Medical Scientist Training Program, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States
| | - Hachung Chung
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States.
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14
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Liu D, He W, Yang LL. Revitalizing antitumor immunity: Leveraging nucleic acid sensors as therapeutic targets. Cancer Lett 2024; 588:216729. [PMID: 38387757 DOI: 10.1016/j.canlet.2024.216729] [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: 11/15/2023] [Revised: 01/30/2024] [Accepted: 02/12/2024] [Indexed: 02/24/2024]
Abstract
Nucleic acid sensors play a critical role in recognizing and responding to pathogenic nucleic acids as danger signals. Upon activation, these sensors initiate downstream signaling cascades that lead to the production and release of pro-inflammatory cytokines, chemokines, and type I interferons. These immune mediators orchestrate diverse effector responses, including the activation of immune cells and the modulation of the tumor microenvironment. However, careful consideration must be given to balancing the activation of nucleic acid sensors to avoid unwanted autoimmune or inflammatory responses. In this review, we provide an overview of nucleic acid sensors and their role in combating cancer through the perception of various aberrant nucleic acids and activation of the immune system. We discuss the connections between different programmed cell death modes and nucleic acid sensors. Finally, we outline the development of nucleic acid sensor agonists, highlighting how their potential as therapeutic targets opens up new avenues for cancer immunotherapy.
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Affiliation(s)
- Danfeng Liu
- Department of Stomatology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China
| | - Wei He
- Department of Stomatology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China.
| | - Lei-Lei Yang
- Department of Stomatology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China.
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15
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Smith ME, Wahl D, Cavalier AN, McWilliams GT, Rossman MJ, Giordano GR, Bryan AD, Seals DR, LaRocca TJ. Repetitive element transcript accumulation is associated with inflammaging in humans. GeroScience 2024:10.1007/s11357-024-01126-y. [PMID: 38641753 DOI: 10.1007/s11357-024-01126-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 03/08/2024] [Indexed: 04/21/2024] Open
Abstract
Chronic, low-grade inflammation increases with aging, contributing to functional declines and diseases that reduce healthspan. Growing evidence suggests that transcripts from repetitive elements (RE) in the genome contribute to this "inflammaging" by stimulating innate immune activation, but evidence of RE-associated inflammation with aging in humans is limited. Here, we present transcriptomic and clinical data showing that RE transcript levels are positively related to gene expression of innate immune sensors, and to serum interleukin 6 (a marker of systemic inflammation), in a large group of middle-aged and older adults. We also: (1) use transcriptomics and whole-genome bisulfite (methylation) sequencing to show that many RE may be hypomethylated with aging, and that aerobic exercise, a healthspan-extending intervention, reduces RE transcript levels and increases RE methylation in older adults; and (2) extend our findings in a secondary dataset demonstrating age-related changes in RE chromatin accessibility. Collectively, our data support the idea that age-related RE transcript accumulation may play a role in inflammaging in humans, and that RE dysregulation with aging may be due in part to upstream epigenetic changes.
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Affiliation(s)
- Meghan E Smith
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Devin Wahl
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Alyssa N Cavalier
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Gabriella T McWilliams
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Matthew J Rossman
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Gregory R Giordano
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO, USA
| | - Angela D Bryan
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO, USA
| | - Douglas R Seals
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Thomas J LaRocca
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA.
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16
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Mendoza HG, Beal PA. Structural and functional effects of inosine modification in mRNA. RNA (NEW YORK, N.Y.) 2024; 30:512-520. [PMID: 38531652 PMCID: PMC11019749 DOI: 10.1261/rna.079977.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 02/09/2024] [Indexed: 03/28/2024]
Abstract
Inosine (I), resulting from the deamination of adenosine (A), is a prominent modification in the human transcriptome. The enzymes responsible for the conversion of adenosine to inosine in human mRNAs are the ADARs (adenosine deaminases acting on RNA). Inosine modification introduces a layer of complexity to mRNA processing and function, as it can impact various aspects of RNA biology, including mRNA stability, splicing, translation, and protein binding. The relevance of this process is emphasized in the growing number of human disorders associated with dysregulated A-to-I editing pathways. Here, we describe the impact of the A-to-I conversion on the structure and stability of duplex RNA and on the consequences of this modification at different locations in mRNAs. Furthermore, we highlight specific open questions regarding the interplay between inosine formation in duplex RNA and the innate immune response.
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Affiliation(s)
- Herra G Mendoza
- Department of Chemistry, University of California, Davis, California 95616, USA
| | - Peter A Beal
- Department of Chemistry, University of California, Davis, California 95616, USA
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17
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Jarmoskaite I, Li JB. Multifaceted roles of RNA editing enzyme ADAR1 in innate immunity. RNA (NEW YORK, N.Y.) 2024; 30:500-511. [PMID: 38531645 PMCID: PMC11019752 DOI: 10.1261/rna.079953.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 02/09/2024] [Indexed: 03/28/2024]
Abstract
Innate immunity must be tightly regulated to enable sensitive pathogen detection while averting autoimmunity triggered by pathogen-like host molecules. A hallmark of viral infection, double-stranded RNAs (dsRNAs) are also abundantly encoded in mammalian genomes, necessitating surveillance mechanisms to distinguish "self" from "nonself." ADAR1, an RNA editing enzyme, has emerged as an essential safeguard against dsRNA-induced autoimmunity. By converting adenosines to inosines (A-to-I) in long dsRNAs, ADAR1 covalently marks endogenous dsRNAs, thereby blocking the activation of the cytoplasmic dsRNA sensor MDA5. Moreover, beyond its editing function, ADAR1 binding to dsRNA impedes the activation of innate immune sensors PKR and ZBP1. Recent landmark studies underscore the utility of silencing ADAR1 for cancer immunotherapy, by exploiting the ADAR1-dependence developed by certain tumors to unleash an antitumor immune response. In this perspective, we summarize the genetic and mechanistic evidence for ADAR1's multipronged role in suppressing dsRNA-mediated autoimmunity and explore the evolving roles of ADAR1 as an immuno-oncology target.
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Affiliation(s)
- Inga Jarmoskaite
- Department of Genetics, Stanford University, Stanford, California 94305, USA
- AIRNA Corporation, Cambridge, Massachusetts 02142, USA
| | - Jin Billy Li
- Department of Genetics, Stanford University, Stanford, California 94305, USA
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18
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Cheng D, Zhu J, Liu G, Gack MU, MacDuff DA. HOIL1 mediates MDA5 activation through ubiquitination of LGP2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.02.587772. [PMID: 38617308 PMCID: PMC11014604 DOI: 10.1101/2024.04.02.587772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
The RIG-I-like receptors (RLRs), RIG-I and MDA5, are innate sensors of RNA virus infections that are critical for mounting a robust antiviral immune response. We have shown previously that HOIL1, a component of the Linear Ubiquitin Chain Assembly Complex (LUBAC), is essential for interferon (IFN) induction in response to viruses sensed by MDA5, but not for viruses sensed by RIG-I. LUBAC contains two unusual E3 ubiquitin ligases, HOIL1 and HOIP. HOIP generates methionine-1-linked polyubiquitin chains, whereas HOIL1 has recently been shown to conjugate ubiquitin onto serine and threonine residues. Here, we examined the differential requirement for HOIL1 and HOIP E3 ligase activities in RLR-mediated IFN induction. We determined that HOIL1 E3 ligase activity was critical for MDA5-dependent IFN induction, while HOIP E3 ligase activity played only a modest role in promoting IFN induction. HOIL1 E3 ligase promoted MDA5 oligomerization, its translocation to mitochondrial-associated membranes, and the formation of MAVS aggregates. We identified that HOIL1 can interact with and facilitate the ubiquitination of LGP2, a positive regulator of MDA5 oligomerization. In summary, our work identifies LGP2 ubiquitination by HOIL1 in facilitating the activation of MDA5 and the induction of a robust IFN response.
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Affiliation(s)
- Deion Cheng
- . Department of Microbiology and Immunology, University of Illinois Chicago College of Medicine, Chicago, Illinois, USA
| | - Junji Zhu
- . Cleveland Clinic Florida Research and Innovation Center, Port St. Lucie, Florida, USA
| | - GuanQun Liu
- . Cleveland Clinic Florida Research and Innovation Center, Port St. Lucie, Florida, USA
| | - Michaela U. Gack
- . Cleveland Clinic Florida Research and Innovation Center, Port St. Lucie, Florida, USA
| | - Donna A. MacDuff
- . Department of Microbiology and Immunology, University of Illinois Chicago College of Medicine, Chicago, Illinois, USA
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19
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de Reuver R, Maelfait J. Novel insights into double-stranded RNA-mediated immunopathology. Nat Rev Immunol 2024; 24:235-249. [PMID: 37752355 DOI: 10.1038/s41577-023-00940-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2023] [Indexed: 09/28/2023]
Abstract
Recent progress in human and mouse genetics has transformed our understanding of the molecular mechanisms by which recognition of self double-stranded RNA (self-dsRNA) causes immunopathology. Novel mouse models recapitulate loss-of-function mutations in the RNA editing enzyme ADAR1 that are found in patients with Aicardi-Goutières syndrome (AGS) - a monogenic inflammatory disease associated with increased levels of type I interferon. Extensive analyses of the genotype-phenotype relationships in these mice have now firmly established a causal relationship between increased intracellular concentrations of endogenous immunostimulatory dsRNA and type I interferon-driven immunopathology. Activation of the dsRNA-specific immune sensor MDA5 perpetuates the overproduction of type I interferons, and chronic engagement of the interferon-inducible innate immune receptors PKR and ZBP1 by dsRNA drives immunopathology by activating an integrated stress response or by inducing excessive cell death. Biochemical and genetic data support a role for the p150 isoform of ADAR1 in the cytosol in suppressing the spontaneous, pathological response to self-dsRNA.
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Affiliation(s)
- Richard de Reuver
- VIB-UGent Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Jonathan Maelfait
- VIB-UGent Center for Inflammation Research, Ghent, Belgium.
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
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20
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Lee M, Ahmad SF, Xu J. Regulation and function of transposable elements in cancer genomes. Cell Mol Life Sci 2024; 81:157. [PMID: 38556602 PMCID: PMC10982106 DOI: 10.1007/s00018-024-05195-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 04/02/2024]
Abstract
Over half of human genomic DNA is composed of repetitive sequences generated throughout evolution by prolific mobile genetic parasites called transposable elements (TEs). Long disregarded as "junk" or "selfish" DNA, TEs are increasingly recognized as formative elements in genome evolution, wired intimately into the structure and function of the human genome. Advances in sequencing technologies and computational methods have ushered in an era of unprecedented insight into how TE activity impacts human biology in health and disease. Here we discuss the current views on how TEs have shaped the regulatory landscape of the human genome, how TE activity is implicated in human cancers, and how recent findings motivate novel strategies to leverage TE activity for improved cancer therapy. Given the crucial role of methodological advances in TE biology, we pair our conceptual discussions with an in-depth review of the inherent technical challenges in studying repeats, specifically related to structural variation, expression analyses, and chromatin regulation. Lastly, we provide a catalog of existing and emerging assays and bioinformatic software that altogether are enabling the most sophisticated and comprehensive investigations yet into the regulation and function of interspersed repeats in cancer genomes.
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Affiliation(s)
- Michael Lee
- Department of Pediatrics, Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, 6000 Harry Hines Blvd., Dallas, TX, 75390, USA.
| | - Syed Farhan Ahmad
- Department of Pathology, Center of Excellence for Leukemia Studies, St. Jude Children's Research Hospital, 262 Danny Thomas Place - MS 345, Memphis, TN, 38105, USA
| | - Jian Xu
- Department of Pathology, Center of Excellence for Leukemia Studies, St. Jude Children's Research Hospital, 262 Danny Thomas Place - MS 345, Memphis, TN, 38105, USA.
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21
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Yang K, Jeltema D, Yan N. Innate immune sensing of macromolecule homeostasis. Adv Immunol 2024; 161:17-51. [PMID: 38763701 DOI: 10.1016/bs.ai.2024.03.004] [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] [Indexed: 05/21/2024]
Abstract
The innate immune system uses a distinct set of germline-encoded pattern recognition receptors to recognize molecular patterns initially thought to be unique to microbial invaders, named pathogen-associated molecular patterns. The concept was later further developed to include similar molecular patterns originating from host cells during tissue damage, known as damage-associated molecular patterns. However, recent advances in the mechanism of monogenic inflammatory diseases have highlighted a much more expansive repertoire of cellular functions that are monitored by innate immunity. Here, we summarize several examples in which an innate immune response is triggered when homeostasis of macromolecule in the cell is disrupted in non-infectious or sterile settings. These ever-growing sensing mechanisms expand the repertoire of innate immune recognition, positioning it not only as a key player in host defense but also as a gatekeeper of cellular homeostasis. Therapeutics inspired by these advances to restore cellular homeostasis and correct the immune system could have far-reaching implications.
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Affiliation(s)
- Kun Yang
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Devon Jeltema
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Nan Yan
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States.
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22
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Zhou Y, Panhale A, Shvedunova M, Balan M, Gomez-Auli A, Holz H, Seyfferth J, Helmstädter M, Kayser S, Zhao Y, Erdogdu NU, Grzadzielewska I, Mittler G, Manke T, Akhtar A. RNA damage compartmentalization by DHX9 stress granules. Cell 2024; 187:1701-1718.e28. [PMID: 38503283 DOI: 10.1016/j.cell.2024.02.028] [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: 07/05/2023] [Revised: 10/24/2023] [Accepted: 02/22/2024] [Indexed: 03/21/2024]
Abstract
Biomolecules incur damage during stress conditions, and damage partitioning represents a vital survival strategy for cells. Here, we identified a distinct stress granule (SG), marked by dsRNA helicase DHX9, which compartmentalizes ultraviolet (UV)-induced RNA, but not DNA, damage. Our FANCI technology revealed that DHX9 SGs are enriched in damaged intron RNA, in contrast to classical SGs that are composed of mature mRNA. UV exposure causes RNA crosslinking damage, impedes intron splicing and decay, and triggers DHX9 SGs within daughter cells. DHX9 SGs promote cell survival and induce dsRNA-related immune response and translation shutdown, differentiating them from classical SGs that assemble downstream of translation arrest. DHX9 modulates dsRNA abundance in the DHX9 SGs and promotes cell viability. Autophagy receptor p62 is activated and important for DHX9 SG disassembly. Our findings establish non-canonical DHX9 SGs as a dedicated non-membrane-bound cytoplasmic compartment that safeguards daughter cells from parental RNA damage.
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Affiliation(s)
- Yilong Zhou
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Amol Panhale
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Maria Shvedunova
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Mirela Balan
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | | | - Herbert Holz
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Janine Seyfferth
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Martin Helmstädter
- EMcore, Renal Division, Department of Medicine, University Freiburg, Hospital Freiburg, University Faculty of Medicine, Freiburg, Germany
| | - Séverine Kayser
- EMcore, Renal Division, Department of Medicine, University Freiburg, Hospital Freiburg, University Faculty of Medicine, Freiburg, Germany
| | - Yuling Zhao
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany; International Max Planck Research School for Molecular and Cellular Biology (IMPRS-MCB), Freiburg, Germany
| | - Niyazi Umut Erdogdu
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany; International Max Planck Research School for Molecular and Cellular Biology (IMPRS-MCB), Freiburg, Germany
| | - Iga Grzadzielewska
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany; International Max Planck Research School for Molecular and Cellular Biology (IMPRS-MCB), Freiburg, Germany
| | - Gerhard Mittler
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Thomas Manke
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Asifa Akhtar
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany.
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23
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Ku J, Lee K, Ku D, Kim S, Lee J, Bang H, Kim N, Do H, Lee H, Lim C, Han J, Lee YS, Kim Y. Alternative polyadenylation determines the functional landscape of inverted Alu repeats. Mol Cell 2024; 84:1062-1077.e9. [PMID: 38309276 DOI: 10.1016/j.molcel.2024.01.008] [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: 06/14/2023] [Revised: 11/27/2023] [Accepted: 01/09/2024] [Indexed: 02/05/2024]
Abstract
Inverted Alu repeats (IRAlus) are abundantly found in the transcriptome, especially in introns and 3' untranslated regions (UTRs). Yet, the biological significance of IRAlus embedded in 3' UTRs remains largely unknown. Here, we find that 3' UTR IRAlus silences genes involved in essential signaling pathways. We utilize J2 antibody to directly capture and map the double-stranded RNA structure of 3' UTR IRAlus in the transcriptome. Bioinformatic analysis reveals alternative polyadenylation as a major axis of IRAlus-mediated gene regulation. Notably, the expression of mouse double minute 2 (MDM2), an inhibitor of p53, is upregulated by the exclusion of IRAlus during UTR shortening, which is exploited to silence p53 during tumorigenesis. Moreover, the transcriptome-wide UTR lengthening in neural progenitor cells results in the global downregulation of genes associated with neurodegenerative diseases, including amyotrophic lateral sclerosis, via IRAlus inclusion. Our study establishes the functional landscape of 3' UTR IRAlus and its role in human pathophysiology.
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Affiliation(s)
- Jayoung Ku
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Keonyong Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Doyeong Ku
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Sujin Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Jongbin Lee
- Research Center for Cellular Identity, KAIST, Daejeon 34141, Korea
| | - Hyunwoo Bang
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea
| | - Namwook Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Hyunsu Do
- Graduate School of Medical Science and Engineering, KAIST, Daejeon 34141, Korea
| | - Hyeonjung Lee
- Department of Bio and Brain Engineering, KAIST, Daejeon 34141, Korea
| | - Chunghun Lim
- Department of Biological Sciences, KAIST, Daejeon 34141, Korea
| | - Jinju Han
- Graduate School of Medical Science and Engineering, KAIST, Daejeon 34141, Korea; BioMedical Research Center, KAIST, Daejeon 34141, Korea
| | - Young-Suk Lee
- Department of Bio and Brain Engineering, KAIST, Daejeon 34141, Korea; Graduate School of Engineering Biology, KAIST, Daejeon 34141, Korea.
| | - Yoosik Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea; Graduate School of Engineering Biology, KAIST, Daejeon 34141, Korea; KAIST Institute for BioCentury, KAIST, Daejeon 34141, Korea; KAIST Institute for Health Science and Technology (KIHST), KAIST, Daejeon 34141, Korea; BioProcess Engineering Research Center and BioInformatics Research Center, KAIST, Daejeon 34141, Korea.
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24
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Liu H, Liu YX, Fan W, Fan B. Metformin switches cell death modes to soothe the apical periodontitis via ZBP1. FASEB J 2024; 38:e23549. [PMID: 38446465 DOI: 10.1096/fj.202302073r] [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: 10/11/2023] [Revised: 01/08/2024] [Accepted: 02/26/2024] [Indexed: 03/07/2024]
Abstract
Apical periodontitis (AP) is a disease caused by pathogenic microorganisms and featured with the degradation of periapical hard tissue. Our recent research showed the crucial role of Z-DNA binding protein 1 (ZBP1)-mediated necroptosis and apoptosis in the pathogenesis of AP. However, the specific regulatory mechanisms of ZBP1 in AP are not fully elucidated. It was found that metformin has a regulatory role in cell necroptosis and apoptosis. But whether and how metformin regulates necroptosis and apoptosis through the ZBP1 in the context of AP remains unknown. This study provided evidence that lipopolysaccharide (LPS) promotes the synthesis of left-handed Z-nucleic acids (Z-NA), which in turn activates ZBP1. Knockout of Zbp1 by CRISPR/Cas9 technology significantly reduced LPS-induced necroptosis and apoptosis in vitro. By using Zbp1-knockout mice, periapical bone destruction was alleviated. Moreover, type I interferon induced the expression of interferon-stimulated genes (ISGs), which serve as a major source of Z-NA. In addition, the RNA-editing enzyme Adenosine Deaminase RNA specific 1 (ADAR1) prevented the accumulation of endogenous Z-NA. Meanwhile, metformin suppressed the ZBP1-mediated necroptosis by inhibiting the expression of ZBP1 and the accumulation of ISGs. Metformin also promoted mitochondrial apoptosis, which is critical for the elimination of intracellular bacterial infection. The enhanced apoptosis further promoted the healing of infected apical bone tissues. In summary, these results demonstrated that the recognition of Z-NA by ZBP1 plays an important role in AP pathogenesis. Metformin suppressed ZBP1-mediated necroptosis and promoted apoptosis, thereby contributing to the soothing of inflammation and bone healing in AP.
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Affiliation(s)
- Hui Liu
- The State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Yu-Xuan Liu
- The State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Wei Fan
- The State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Bing Fan
- The State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, China
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25
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Singh R, Wu Y, Herrero Del Valle A, Leigh KE, Mong S, Cheng MTK, Ferguson BJ, Modis Y. Contrasting functions of ATP hydrolysis by MDA5 and LGP2 in viral RNA sensing. J Biol Chem 2024; 300:105711. [PMID: 38309507 PMCID: PMC10909783 DOI: 10.1016/j.jbc.2024.105711] [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: 08/30/2023] [Revised: 01/16/2024] [Accepted: 01/24/2024] [Indexed: 02/05/2024] Open
Abstract
Cytosolic long dsRNA, among the most potent proinflammatory signals, is recognized by melanoma differentiation-associated protein 5 (MDA5). MDA5 binds dsRNA cooperatively forming helical filaments. ATP hydrolysis by MDA5 fulfills a proofreading function by promoting dissociation of shorter endogenous dsRNs from MDA5 while allowing longer viral dsRNAs to remain bound leading to activation of interferon-β responses. Here, we show that adjacent MDA5 subunits in MDA5-dsRNA filaments hydrolyze ATP cooperatively, inducing cooperative filament disassembly. Consecutive rounds of ATP hydrolysis amplify the filament footprint, displacing tightly bound proteins from dsRNA. Our electron microscopy and biochemical assays show that LGP2 binds to dsRNA at internal binding sites through noncooperative ATP hydrolysis. Unlike MDA5, LGP2 has low nucleic acid selectivity and can hydrolyze GTP and CTP as well as ATP. Binding of LGP2 to dsRNA promotes nucleation of MDA5 filament assembly resulting in shorter filaments. Molecular modeling identifies an internally bound MDA5-LGP2-RNA complex, with the LGP2 C-terminal tail forming the key contacts with MDA5. These contacts are specifically required for NTP-dependent internal RNA binding. We conclude that NTPase-dependent binding of LGP2 to internal dsRNA sites complements NTPase-independent binding to dsRNA ends, via distinct binding modes, to increase the number and signaling output of MDA5-dsRNA complexes.
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Affiliation(s)
- Rahul Singh
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK; Department of Pathology, University of Cambridge, Cambridge, UK
| | - Yuan Wu
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK
| | - Alba Herrero Del Valle
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK
| | - Kendra E Leigh
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK
| | - Sai Mong
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK
| | - Mark T K Cheng
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK
| | - Brian J Ferguson
- Department of Pathology, University of Cambridge, Cambridge, UK.
| | - Yorgo Modis
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK.
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26
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Hosseini A, Lindholm HT, Chen R, Mehdipour P, Marhon SA, Ishak CA, Moore PC, Classon M, Di Gioacchino A, Greenbaum B, De Carvalho DD. Retroelement decay by the exonuclease XRN1 is a viral mimicry dependency in cancer. Cell Rep 2024; 43:113684. [PMID: 38261511 DOI: 10.1016/j.celrep.2024.113684] [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: 07/06/2023] [Revised: 10/31/2023] [Accepted: 01/03/2024] [Indexed: 01/25/2024] Open
Abstract
Viral mimicry describes the immune response induced by endogenous stimuli such as double-stranded RNA (dsRNA) from endogenous retroelements. Activation of viral mimicry has the potential to kill cancer cells or augment anti-tumor immune responses. Here, we systematically identify mechanisms of viral mimicry adaptation associated with cancer cell dependencies. Among the top hits is the RNA decay protein XRN1 as an essential gene for the survival of a subset of cancer cell lines. XRN1 dependency is mediated by mitochondrial antiviral signaling protein and protein kinase R activation and is associated with higher levels of cytosolic dsRNA, higher levels of a subset of Alus capable of forming dsRNA, and higher interferon-stimulated gene expression, indicating that cells die due to induction of viral mimicry. Furthermore, dsRNA-inducing drugs such as 5-aza-2'-deoxycytidine and palbociclib can generate a synthetic dependency on XRN1 in cells initially resistant to XRN1 knockout. These results indicate that XRN1 is a promising target for future cancer therapeutics.
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Affiliation(s)
- Amir Hosseini
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Håvard T Lindholm
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Pathology, Oslo University Hospital-Rikshospitalet, 0372 Oslo, Norway
| | - Raymond Chen
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Parinaz Mehdipour
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Sajid A Marhon
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Charles A Ishak
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Paul C Moore
- Pfizer Centers for Therapeutic Innovation, South San Francisco, CA 94080, USA
| | - Marie Classon
- Pfizer Centers for Therapeutic Innovation, South San Francisco, CA 94080, USA
| | - Andrea Di Gioacchino
- Laboratoire de Physique de l'Ecole Normale Supérieure, PSL & CNRS UMR8063, Sorbonne Université, Université de Paris, Paris, France
| | - Benjamin Greenbaum
- Physiology, Biophysics & Systems Biology, Weill Cornell Medicine, Weill Cornell Medical College, New York, NY 10065, USA; Computational Oncology, Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Daniel D De Carvalho
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
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27
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Yang K, Tang Z, Xing C, Yan N. STING signaling in the brain: Molecular threats, signaling activities, and therapeutic challenges. Neuron 2024; 112:539-557. [PMID: 37944521 PMCID: PMC10922189 DOI: 10.1016/j.neuron.2023.10.014] [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: 08/31/2023] [Revised: 10/06/2023] [Accepted: 10/11/2023] [Indexed: 11/12/2023]
Abstract
Stimulator of interferon genes (STING) is an innate immune signaling protein critical to infections, autoimmunity, and cancer. STING signaling is also emerging as an exciting and integral part of many neurological diseases. Here, we discuss recent advances in STING signaling in the brain. We summarize how molecular threats activate STING signaling in the diseased brain and how STING signaling activities in glial and neuronal cells cause neuropathology. We also review human studies of STING neurobiology and consider therapeutic challenges in targeting STING to treat neurological diseases.
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Affiliation(s)
- Kun Yang
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Zhen Tang
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Cong Xing
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Nan Yan
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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28
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Baldwin ET, van Eeuwen T, Hoyos D, Zalevsky A, Tchesnokov EP, Sánchez R, Miller BD, Di Stefano LH, Ruiz FX, Hancock M, Işik E, Mendez-Dorantes C, Walpole T, Nichols C, Wan P, Riento K, Halls-Kass R, Augustin M, Lammens A, Jestel A, Upla P, Xibinaku K, Congreve S, Hennink M, Rogala KB, Schneider AM, Fairman JE, Christensen SM, Desrosiers B, Bisacchi GS, Saunders OL, Hafeez N, Miao W, Kapeller R, Zaller DM, Sali A, Weichenrieder O, Burns KH, Götte M, Rout MP, Arnold E, Greenbaum BD, Romero DL, LaCava J, Taylor MS. Structures, functions and adaptations of the human LINE-1 ORF2 protein. Nature 2024; 626:194-206. [PMID: 38096902 PMCID: PMC10830420 DOI: 10.1038/s41586-023-06947-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 12/07/2023] [Indexed: 01/05/2024]
Abstract
The LINE-1 (L1) retrotransposon is an ancient genetic parasite that has written around one-third of the human genome through a 'copy and paste' mechanism catalysed by its multifunctional enzyme, open reading frame 2 protein (ORF2p)1. ORF2p reverse transcriptase (RT) and endonuclease activities have been implicated in the pathophysiology of cancer2,3, autoimmunity4,5 and ageing6,7, making ORF2p a potential therapeutic target. However, a lack of structural and mechanistic knowledge has hampered efforts to rationally exploit it. We report structures of the human ORF2p 'core' (residues 238-1061, including the RT domain) by X-ray crystallography and cryo-electron microscopy in several conformational states. Our analyses identified two previously undescribed folded domains, extensive contacts to RNA templates and associated adaptations that contribute to unique aspects of the L1 replication cycle. Computed integrative structural models of full-length ORF2p show a dynamic closed-ring conformation that appears to open during retrotransposition. We characterize ORF2p RT inhibition and reveal its underlying structural basis. Imaging and biochemistry show that non-canonical cytosolic ORF2p RT activity can produce RNA:DNA hybrids, activating innate immune signalling through cGAS/STING and resulting in interferon production6-8. In contrast to retroviral RTs, L1 RT is efficiently primed by short RNAs and hairpins, which probably explains cytosolic priming. Other biochemical activities including processivity, DNA-directed polymerization, non-templated base addition and template switching together allow us to propose a revised L1 insertion model. Finally, our evolutionary analysis demonstrates structural conservation between ORF2p and other RNA- and DNA-dependent polymerases. We therefore provide key mechanistic insights into L1 polymerization and insertion, shed light on the evolutionary history of L1 and enable rational drug development targeting L1.
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Affiliation(s)
| | - Trevor van Eeuwen
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
| | - David Hoyos
- Computational Oncology, Department of Epidemiology & Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Arthur Zalevsky
- Department of Bioengineering and Therapeutic Sciences University of California, San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
- Quantitative Biology Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Egor P Tchesnokov
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | | | - Bryant D Miller
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Luciano H Di Stefano
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, The Netherlands
| | - Francesc Xavier Ruiz
- Center for Advanced Biotechnology and Medicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, USA
| | - Matthew Hancock
- Department of Bioengineering and Therapeutic Sciences University of California, San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
- Quantitative Biology Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Esin Işik
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Carlos Mendez-Dorantes
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Thomas Walpole
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Charles Nichols
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Paul Wan
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Kirsi Riento
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Rowan Halls-Kass
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | | | - Alfred Lammens
- Proteros Biostructures GmbH, Martinsried, Planegg, Germany
| | - Anja Jestel
- Proteros Biostructures GmbH, Martinsried, Planegg, Germany
| | - Paula Upla
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
| | - Kera Xibinaku
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | | | | | - Kacper B Rogala
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Anna M Schneider
- Structural Biology of Selfish RNA, Department of Protein Evolution, Max Planck Institute for Biology, Tübingen, Germany
| | | | | | | | | | | | | | | | | | | | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences University of California, San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
- Quantitative Biology Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Oliver Weichenrieder
- Structural Biology of Selfish RNA, Department of Protein Evolution, Max Planck Institute for Biology, Tübingen, Germany
| | - Kathleen H Burns
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA.
| | - Matthias Götte
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA.
| | - Eddy Arnold
- Center for Advanced Biotechnology and Medicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, USA.
| | - Benjamin D Greenbaum
- Computational Oncology, Department of Epidemiology & Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
- Physiology, Biophysics & Systems Biology, Weill Cornell Medicine, Weill Cornell Medical College, New York, NY, USA.
| | | | - John LaCava
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA.
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, The Netherlands.
| | - Martin S Taylor
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
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29
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Dohnalová H, Seifert M, Matoušková E, Klein M, Papini FS, Lipfert J, Dulin D, Lankaš F. Temperature-Dependent Twist of Double-Stranded RNA Probed by Magnetic Tweezer Experiments and Molecular Dynamics Simulations. J Phys Chem B 2024; 128:664-675. [PMID: 38197365 PMCID: PMC10823466 DOI: 10.1021/acs.jpcb.3c06280] [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: 09/19/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 01/11/2024]
Abstract
RNA plays critical roles in the transmission and regulation of genetic information and is increasingly used in biomedical and biotechnological applications. Functional RNAs contain extended double-stranded regions, and the structure of double-stranded RNA (dsRNA) has been revealed at high resolution. However, the dependence of the properties of the RNA double helix on environmental effects, notably temperature, is still poorly understood. Here, we use single-molecule magnetic tweezer measurements to determine the dependence of the dsRNA twist on temperature. We find that dsRNA unwinds with increasing temperature, even more than DNA, with ΔTwRNA = -14.4 ± 0.7°/(°C·kbp), compared to ΔTwDNA = -11.0 ± 1.2°/(°C·kbp). All-atom molecular dynamics (MD) simulations using a range of nucleic acid force fields, ion parameters, and water models correctly predict that dsRNA unwinds with rising temperature but significantly underestimate the magnitude of the effect. These MD data, together with additional MD simulations involving DNA and DNA-RNA hybrid duplexes, reveal a linear correlation between the twist temperature decrease and the helical rise, in line with DNA but at variance with RNA experimental data. We speculate that this discrepancy might be caused by some unknown bias in the RNA force fields tested or by as yet undiscovered transient alternative structures in the RNA duplex. Our results provide a baseline to model more complex RNA assemblies and to test and develop new parametrizations for RNA simulations. They may also inspire physical models of the temperature-dependent dsRNA structure.
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Affiliation(s)
- Hana Dohnalová
- Department
of Informatics and Chemistry, University
of Chemistry and Technology Prague, Technická 5, 166 28 Praha
6, Czech Republic
| | - Mona Seifert
- Junior
Research Group 2, Interdisciplinary Center for Clinical Research, Friedrich-Alexander-University Erlangen-Nürnberg, Cauerstr. 3, Erlangen 91058, Germany
| | - Eva Matoušková
- Department
of Informatics and Chemistry, University
of Chemistry and Technology Prague, Technická 5, 166 28 Praha
6, Czech Republic
| | - Misha Klein
- Department
of Physics and Astronomy and LaserLaB Amsterdam, Vrije Universiteit Amsterdam, De Boelelaan 1081, Amsterdam 1081 HV, The Netherlands
| | - Flávia S. Papini
- Junior
Research Group 2, Interdisciplinary Center for Clinical Research, Friedrich-Alexander-University Erlangen-Nürnberg, Cauerstr. 3, Erlangen 91058, Germany
| | - Jan Lipfert
- Soft
Condensed Matter and Biophysics, Department of Physics and Debye Institute, Utrecht University, Utrecht 3584 CC, The Netherlands
| | - David Dulin
- Junior
Research Group 2, Interdisciplinary Center for Clinical Research, Friedrich-Alexander-University Erlangen-Nürnberg, Cauerstr. 3, Erlangen 91058, Germany
- Department
of Physics and Astronomy and LaserLaB Amsterdam, Vrije Universiteit Amsterdam, De Boelelaan 1081, Amsterdam 1081 HV, The Netherlands
| | - Filip Lankaš
- Department
of Informatics and Chemistry, University
of Chemistry and Technology Prague, Technická 5, 166 28 Praha
6, Czech Republic
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30
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Cottrell KA, Andrews RJ, Bass BL. The competitive landscape of the dsRNA world. Mol Cell 2024; 84:107-119. [PMID: 38118451 PMCID: PMC10843539 DOI: 10.1016/j.molcel.2023.11.033] [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: 10/16/2023] [Revised: 11/20/2023] [Accepted: 11/22/2023] [Indexed: 12/22/2023]
Abstract
The ability to sense and respond to infection is essential for life. Viral infection produces double-stranded RNAs (dsRNAs) that are sensed by proteins that recognize the structure of dsRNA. This structure-based recognition of viral dsRNA allows dsRNA sensors to recognize infection by many viruses, but it comes at a cost-the dsRNA sensors cannot always distinguish between "self" and "nonself" dsRNAs. "Self" RNAs often contain dsRNA regions, and not surprisingly, mechanisms have evolved to prevent aberrant activation of dsRNA sensors by "self" RNA. Here, we review current knowledge about the life of endogenous dsRNAs in mammals-the biosynthesis and processing of dsRNAs, the proteins they encounter, and their ultimate degradation. We highlight mechanisms that evolved to prevent aberrant dsRNA sensor activation and the importance of competition in the regulation of dsRNA sensors and other dsRNA-binding proteins.
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Affiliation(s)
- Kyle A Cottrell
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA.
| | - Ryan J Andrews
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Brenda L Bass
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
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31
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Knebel UE, Peleg S, Dai C, Cohen-Fultheim R, Jonsson S, Poznyak K, Israeli M, Zamashanski L, Glaser B, Levanon EY, Powers AC, Klochendler A, Dor Y. Disrupted RNA editing in beta cells mimics early-stage type 1 diabetes. Cell Metab 2024; 36:48-61.e6. [PMID: 38128529 PMCID: PMC10843671 DOI: 10.1016/j.cmet.2023.11.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 09/18/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023]
Abstract
A major hypothesis for the etiology of type 1 diabetes (T1D) postulates initiation by viral infection, leading to double-stranded RNA (dsRNA)-mediated interferon response and inflammation; however, a causal virus has not been identified. Here, we use a mouse model, corroborated with human islet data, to demonstrate that endogenous dsRNA in beta cells can lead to a diabetogenic immune response, thus identifying a virus-independent mechanism for T1D initiation. We found that disruption of the RNA editing enzyme adenosine deaminases acting on RNA (ADAR) in beta cells triggers a massive interferon response, islet inflammation, and beta cell failure and destruction, with features bearing striking similarity to early-stage human T1D. Glycolysis via calcium enhances the interferon response, suggesting an actionable vicious cycle of inflammation and increased beta cell workload.
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Affiliation(s)
- Udi Ehud Knebel
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel; Department of Military Medicine and "Tzameret", Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel, and Medical Corps, Israel Defense Forces, Israel
| | - Shani Peleg
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Chunhua Dai
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Roni Cohen-Fultheim
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel; Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, Israel
| | - Sara Jonsson
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Karin Poznyak
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Maya Israeli
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Liza Zamashanski
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Benjamin Glaser
- Department of Endocrinology and Metabolism, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Erez Y Levanon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Alvin C Powers
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; VA Tennessee Valley Healthcare System, Nashville, TN 37212, USA
| | - Agnes Klochendler
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
| | - Yuval Dor
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
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32
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Sun X, Yang Y, Meng X, Li J, Liu X, Liu H. PANoptosis: Mechanisms, biology, and role in disease. Immunol Rev 2024; 321:246-262. [PMID: 37823450 DOI: 10.1111/imr.13279] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/16/2023] [Accepted: 09/19/2023] [Indexed: 10/13/2023]
Abstract
Cell death can be executed through distinct subroutines. PANoptosis is a unique inflammatory cell death modality involving the interactions between pyroptosis, apoptosis, and necroptosis, which can be mediated by multifaceted PANoptosome complexes assembled via integrating components from other cell death modalities. There is growing interest in the process and function of PANoptosis. Accumulating evidence suggests that PANoptosis occurs under diverse stimuli, for example, viral or bacterial infection, cytokine storm, and cancer. Given the impact of PANoptosis across the disease spectrum, this review briefly describes the relationships between pyroptosis, apoptosis, and necroptosis, highlights the key molecules in PANoptosome formation and PANoptosis activation, and outlines the multifaceted roles of PANoptosis in diseases together with a potential for therapeutic targeting. We also discuss important concepts and pressing issues for future PANoptosis research. Improved understanding of PANoptosis and its mechanisms is crucial for identifying novel therapeutic targets and strategies.
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Affiliation(s)
- Xu Sun
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Yanpeng Yang
- Cardiac Care Unit, Zhengzhou Central Hospital Affiliated to Zhengzhou University, Zhengzhou, China
| | - Xiaona Meng
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Jia Li
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Xiaoli Liu
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Huaimin Liu
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
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33
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Weng S, Yang X, Yu N, Wang PC, Xiong S, Ruan H. Harnessing ADAR-Mediated Site-Specific RNA Editing in Immune-Related Disease: Prediction and Therapeutic Implications. Int J Mol Sci 2023; 25:351. [PMID: 38203521 PMCID: PMC10779106 DOI: 10.3390/ijms25010351] [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: 10/31/2023] [Revised: 12/15/2023] [Accepted: 12/23/2023] [Indexed: 01/12/2024] Open
Abstract
ADAR (Adenosine Deaminases Acting on RNA) proteins are a group of enzymes that play a vital role in RNA editing by converting adenosine to inosine in RNAs. This process is a frequent post-transcriptional event observed in metazoan transcripts. Recent studies indicate widespread dysregulation of ADAR-mediated RNA editing across many immune-related diseases, such as human cancer. We comprehensively review ADARs' function as pattern recognizers and their capability to contribute to mediating immune-related pathways. We also highlight the potential role of site-specific RNA editing in maintaining homeostasis and its relationship to various diseases, such as human cancers. More importantly, we summarize the latest cutting-edge computational approaches and data resources for predicting and analyzing RNA editing sites. Lastly, we cover the recent advancement in site-directed ADAR editing tool development. This review presents an up-to-date overview of ADAR-mediated RNA editing, how site-specific RNA editing could potentially impact disease pathology, and how they could be harnessed for therapeutic applications.
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Affiliation(s)
- Shenghui Weng
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, China; (S.W.); (P.-C.W.)
| | - Xinyi Yang
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, China; (S.W.); (P.-C.W.)
| | - Nannan Yu
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, China; (S.W.); (P.-C.W.)
| | - Peng-Cheng Wang
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, China; (S.W.); (P.-C.W.)
| | - Sidong Xiong
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, China; (S.W.); (P.-C.W.)
| | - Hang Ruan
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, China; (S.W.); (P.-C.W.)
- MOE Key Laboratory of Geriatric Diseases and Immunology, Suzhou Medical College of Soochow University, Suzhou 215123, China
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de Regt AK, Anand K, Ciupka K, Bender F, Gatterdam K, Putschli B, Fusshöller D, Hilbig D, Kirchhoff A, Hunkler C, Wolter S, Grünewald A, Wallerath C, Schuberth-Wagner C, Ludwig J, Paeschke K, Bartok E, Hagelueken G, Hartmann G, Zillinger T, Geyer M, Schlee M. A conserved isoleucine in the binding pocket of RIG-I controls immune tolerance to mitochondrial RNA. Nucleic Acids Res 2023; 51:11893-11910. [PMID: 37831086 PMCID: PMC10681732 DOI: 10.1093/nar/gkad835] [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: 01/25/2023] [Revised: 09/01/2023] [Accepted: 09/21/2023] [Indexed: 10/14/2023] Open
Abstract
RIG-I is a cytosolic receptor of viral RNA essential for the immune response to numerous RNA viruses. Accordingly, RIG-I must sensitively detect viral RNA yet tolerate abundant self-RNA species. The basic binding cleft and an aromatic amino acid of the RIG-I C-terminal domain(CTD) mediate high-affinity recognition of 5'triphosphorylated and 5'base-paired RNA(dsRNA). Here, we found that, while 5'unmodified hydroxyl(OH)-dsRNA demonstrated residual activation potential, 5'-monophosphate(5'p)-termini, present on most cellular RNAs, prevented RIG-I activation. Determination of CTD/dsRNA co-crystal structures and mutant activation studies revealed that the evolutionarily conserved I875 within the CTD sterically inhibits 5'p-dsRNA binding. RIG-I(I875A) was activated by both synthetic 5'p-dsRNA and endogenous long dsRNA within the polyA-rich fraction of total cellular RNA. RIG-I(I875A) specifically interacted with long, polyA-bearing, mitochondrial(mt) RNA, and depletion of mtRNA from total RNA abolished its activation. Altogether, our study demonstrates that avoidance of 5'p-RNA recognition is crucial to prevent mtRNA-triggered RIG-I-mediated autoinflammation.
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Affiliation(s)
- Ann Kristin de Regt
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Kanchan Anand
- Institute of Structural Biology, University Hospital Bonn, Bonn, Germany
| | - Katrin Ciupka
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Felix Bender
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Karl Gatterdam
- Institute of Structural Biology, University Hospital Bonn, Bonn, Germany
| | - Bastian Putschli
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - David Fusshöller
- Institute of Structural Biology, University Hospital Bonn, Bonn, Germany
| | - Daniel Hilbig
- Department of Oncology, Hematology and Rheumatology, University Hospital Bonn, Bonn, Germany
| | - Alexander Kirchhoff
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Charlotte Hunkler
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Steven Wolter
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Agathe Grünewald
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Christina Wallerath
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | | | - Janos Ludwig
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Katrin Paeschke
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
- Department of Oncology, Hematology and Rheumatology, University Hospital Bonn, Bonn, Germany
| | - Eva Bartok
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
- Institute of Experimental Haematology and Transfusion Medicine, University Hospital Bonn, Bonn, Germany
- Unit of Experimental Immunology, Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Gregor Hagelueken
- Institute of Structural Biology, University Hospital Bonn, Bonn, Germany
| | - Gunther Hartmann
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Thomas Zillinger
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Matthias Geyer
- Institute of Structural Biology, University Hospital Bonn, Bonn, Germany
| | - Martin Schlee
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
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Hu SB, Heraud-Farlow J, Sun T, Liang Z, Goradia A, Taylor S, Walkley CR, Li JB. ADAR1p150 prevents MDA5 and PKR activation via distinct mechanisms to avert fatal autoinflammation. Mol Cell 2023; 83:3869-3884.e7. [PMID: 37797622 DOI: 10.1016/j.molcel.2023.09.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 07/14/2023] [Accepted: 09/12/2023] [Indexed: 10/07/2023]
Abstract
Effective immunity requires the innate immune system to distinguish foreign nucleic acids from cellular ones. Cellular double-stranded RNAs (dsRNAs) are edited by the RNA-editing enzyme ADAR1 to evade being recognized as viral dsRNA by cytoplasmic dsRNA sensors, including MDA5 and PKR. The loss of ADAR1-mediated RNA editing of cellular dsRNA activates MDA5. Additional RNA-editing-independent functions of ADAR1 have been proposed, but a specific mechanism has not been delineated. We now demonstrate that the loss of ADAR1-mediated RNA editing specifically activates MDA5, whereas loss of the cytoplasmic ADAR1p150 isoform or its dsRNA-binding activity enabled PKR activation. Deleting both MDA5 and PKR resulted in complete rescue of the embryonic lethality of Adar1p150-/- mice to adulthood, contrasting with the limited or no rescue by removing MDA5 or PKR alone. Our findings demonstrate that MDA5 and PKR are the primary in vivo effectors of fatal autoinflammation following the loss of ADAR1p150.
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Affiliation(s)
- Shi-Bin Hu
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Jacki Heraud-Farlow
- St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia; Department of Medicine, Eastern Hill Precinct, Melbourne Medical School, University of Melbourne, Fitzroy, VIC 3065, Australia
| | - Tao Sun
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Zhen Liang
- St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia; Department of Medicine, Eastern Hill Precinct, Melbourne Medical School, University of Melbourne, Fitzroy, VIC 3065, Australia
| | - Ankita Goradia
- St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Scott Taylor
- St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Carl R Walkley
- St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia; Department of Medicine, Eastern Hill Precinct, Melbourne Medical School, University of Melbourne, Fitzroy, VIC 3065, Australia.
| | - Jin Billy Li
- Department of Genetics, Stanford University, Stanford, CA 94305, USA.
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Dorrity TJ, Chung H. A tale of two pathways: Two distinct mechanisms of ADAR1 prevent fatal autoinflammation. Mol Cell 2023; 83:3760-3762. [PMID: 37922869 PMCID: PMC11056273 DOI: 10.1016/j.molcel.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 10/11/2023] [Accepted: 10/11/2023] [Indexed: 11/07/2023]
Abstract
In this issue, Hu and Heraud-Farlow et al.1 demonstrate that ADAR1 dsRNA editing and dsRNA binding activities are critical to repress MDA5 and PKR, respectively, and that PKR and MDA5 act in concert to induce fatality in ADAR1 KO mice.
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Affiliation(s)
- Tyler J Dorrity
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Hachung Chung
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA.
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Yamamoto R, Liu Z, Choudhury M, Xiao X. dsRID: in silico identification of dsRNA regions using long-read RNA-seq data. Bioinformatics 2023; 39:btad649. [PMID: 37871161 PMCID: PMC10628436 DOI: 10.1093/bioinformatics/btad649] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 10/02/2023] [Accepted: 10/20/2023] [Indexed: 10/25/2023] Open
Abstract
MOTIVATION Double-stranded RNAs (dsRNAs) are potent triggers of innate immune responses upon recognition by cytosolic dsRNA sensor proteins. Identification of endogenous dsRNAs helps to better understand the dsRNAome and its relevance to innate immunity related to human diseases. RESULTS Here, we report dsRID (double-stranded RNA identifier), a machine-learning-based method to predict dsRNA regions in silico, leveraging the power of long-read RNA-sequencing (RNA-seq) and molecular traits of dsRNAs. Using models trained with PacBio long-read RNA-seq data derived from Alzheimer's disease (AD) brain, we show that our approach is highly accurate in predicting dsRNA regions in multiple datasets. Applied to an AD cohort sequenced by the ENCODE consortium, we characterize the global dsRNA profile with potentially distinct expression patterns between AD and controls. Together, we show that dsRID provides an effective approach to capture global dsRNA profiles using long-read RNA-seq data. AVAILABILITY AND IMPLEMENTATION Software implementation of dsRID, and genomic coordinates of regions predicted by dsRID in all samples are available at the GitHub repository: https://github.com/gxiaolab/dsRID.
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Affiliation(s)
- Ryo Yamamoto
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, CA 90095-1570, United States
| | - Zhiheng Liu
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095-7246, United States
| | - Mudra Choudhury
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095-7246, United States
| | - Xinshu Xiao
- Bioinformatics Interdepartmental Program, University of California, Los Angeles, CA 90095-1570, United States
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095-7246, United States
- Molecular Biology Institute, University of California, Los Angeles, CA 90095-1570, United States
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Dorrity TJ, Shin H, Wiegand KA, Aruda J, Closser M, Jung E, Gertie JA, Leone A, Polfer R, Culbertson B, Yu L, Wu C, Ito T, Huang Y, Steckelberg AL, Wichterle H, Chung H. Long 3'UTRs predispose neurons to inflammation by promoting immunostimulatory double-stranded RNA formation. Sci Immunol 2023; 8:eadg2979. [PMID: 37862432 PMCID: PMC11056275 DOI: 10.1126/sciimmunol.adg2979] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 08/18/2023] [Indexed: 10/22/2023]
Abstract
Loss of RNA homeostasis underlies numerous neurodegenerative and neuroinflammatory diseases. However, the molecular mechanisms that trigger neuroinflammation are poorly understood. Viral double-stranded RNA (dsRNA) triggers innate immune responses when sensed by host pattern recognition receptors (PRRs) present in all cell types. Here, we report that human neurons intrinsically carry exceptionally high levels of immunostimulatory dsRNAs and identify long 3'UTRs as giving rise to neuronal dsRNA structures. We found that the neuron-enriched ELAVL family of genes (ELAVL2, ELAVL3, and ELAVL4) can increase (i) 3'UTR length, (ii) dsRNA load, and (iii) activation of dsRNA-sensing PRRs such as MDA5, PKR, and TLR3. In wild-type neurons, neuronal dsRNAs signaled through PRRs to induce tonic production of the antiviral type I interferon. Depleting ELAVL2 in WT neurons led to global shortening of 3'UTR length, reduced immunostimulatory dsRNA levels, and rendered WT neurons susceptible to herpes simplex virus and Zika virus infection. Neurons deficient in ADAR1, a dsRNA-editing enzyme mutated in the neuroinflammatory disorder Aicardi-Goutières syndrome, exhibited intolerably high levels of dsRNA that triggered PRR-mediated toxic inflammation and neuronal death. Depleting ELAVL2 in ADAR1 knockout neurons led to prolonged neuron survival by reducing immunostimulatory dsRNA levels. In summary, neurons are specialized cells where PRRs constantly sense "self" dsRNAs to preemptively induce protective antiviral immunity, but maintaining RNA homeostasis is paramount to prevent pathological neuroinflammation.
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Affiliation(s)
- Tyler J. Dorrity
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Heegwon Shin
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Kenenni A. Wiegand
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Justin Aruda
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Michael Closser
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
- Department of Neuroscience and Neurology, Columbia University Irving Medical Center, New York, NY, USA
- Center for Motor Neuron Biology and Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Emily Jung
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Jake A. Gertie
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
- Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Medical Scientist Training Program, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Amanda Leone
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Rachel Polfer
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Bruce Culbertson
- Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Medical Scientist Training Program, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Lisa Yu
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Christine Wu
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Takamasa Ito
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Yuefeng Huang
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Anna-Lena Steckelberg
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Hynek Wichterle
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
- Department of Neuroscience and Neurology, Columbia University Irving Medical Center, New York, NY, USA
- Center for Motor Neuron Biology and Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Hachung Chung
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
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McEntee CM, Cavalier AN, LaRocca TJ. ADAR1 suppression causes interferon signaling and transposable element transcript accumulation in human astrocytes. Front Mol Neurosci 2023; 16:1263369. [PMID: 38035265 PMCID: PMC10685929 DOI: 10.3389/fnmol.2023.1263369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/25/2023] [Indexed: 12/02/2023] Open
Abstract
Neuroinflammation is a central mechanism of brain aging and Alzheimer's disease (AD), but the exact causes of age- and AD-related neuroinflammation are incompletely understood. One potential modulator of neuroinflammation is the enzyme adenosine deaminase acting on RNA 1 (ADAR1), which regulates the accumulation of endogenous double-stranded RNA (dsRNA), a pro-inflammatory/innate immune activator. However, the role of ADAR1 and its transcriptomic targets in astrocytes, key mediators of neuroinflammation, have not been comprehensively investigated. Here, we knock down ADAR1 in primary human astrocytes via siRNA transfection and use transcriptomics (RNA-seq) to show that this results in: (1) increased expression of type I interferon and pro-inflammatory signaling pathways and (2) an accumulation of transposable element (TE) transcripts with the potential to form dsRNA. We also show that our findings may be clinically relevant, as ADAR1 gene expression declines with brain aging and AD in humans, and this is associated with a similar increase in TE transcripts. Together, our results suggest an important role for ADAR1 in preventing pro-inflammatory activation of astrocytes in response to endogenous dsRNA with aging and AD.
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Affiliation(s)
- Cali M. McEntee
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
- Center for Healthy Aging, Colorado State University, Fort Collins, CO, United States
| | - Alyssa N. Cavalier
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
- Center for Healthy Aging, Colorado State University, Fort Collins, CO, United States
| | - Thomas J. LaRocca
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
- Center for Healthy Aging, Colorado State University, Fort Collins, CO, United States
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40
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Shen S, Zhang LS. The regulation of antiviral innate immunity through non-m 6A RNA modifications. Front Immunol 2023; 14:1286820. [PMID: 37915585 PMCID: PMC10616867 DOI: 10.3389/fimmu.2023.1286820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 10/04/2023] [Indexed: 11/03/2023] Open
Abstract
The post-transcriptional RNA modifications impact the dynamic regulation of gene expression in diverse biological and physiological processes. Host RNA modifications play an indispensable role in regulating innate immune responses against virus infection in mammals. Meanwhile, the viral RNAs can be deposited with RNA modifications to interfere with the host immune responses. The N6-methyladenosine (m6A) has boosted the recent emergence of RNA epigenetics, due to its high abundance and a transcriptome-wide widespread distribution in mammalian cells, proven to impact antiviral innate immunity. However, the other types of RNA modifications are also involved in regulating antiviral responses, and the functional roles of these non-m6A RNA modifications have not been comprehensively summarized. In this Review, we conclude the regulatory roles of 2'-O-methylation (Nm), 5-methylcytidine (m5C), adenosine-inosine editing (A-to-I editing), pseudouridine (Ψ), N1-methyladenosine (m1A), N7-methylguanosine (m7G), N6,2'-O-dimethyladenosine (m6Am), and N4-acetylcytidine (ac4C) in antiviral innate immunity. We provide a systematic introduction to the biogenesis and functions of these non-m6A RNA modifications in viral RNA, host RNA, and during virus-host interactions, emphasizing the biological functions of RNA modification regulators in antiviral responses. Furthermore, we discussed the recent research progress in the development of antiviral drugs through non-m6A RNA modifications. Collectively, this Review conveys knowledge and inspiration to researchers in multiple disciplines, highlighting the challenges and future directions in RNA epitranscriptome, immunology, and virology.
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Affiliation(s)
- Shenghai Shen
- Division of Life Science, The Hong Kong University of Science and Technology (HKUST), Kowloon, Hong Kong SAR, China
| | - Li-Sheng Zhang
- Division of Life Science, The Hong Kong University of Science and Technology (HKUST), Kowloon, Hong Kong SAR, China
- Department of Chemistry, The Hong Kong University of Science and Technology (HKUST), Kowloon, Hong Kong SAR, China
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41
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Datta R, Adamska JZ, Bhate A, Li JB. A-to-I RNA editing by ADAR and its therapeutic applications: From viral infections to cancer immunotherapy. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 15:e1817. [PMID: 37718249 PMCID: PMC10947335 DOI: 10.1002/wrna.1817] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 08/29/2023] [Accepted: 08/29/2023] [Indexed: 09/19/2023]
Abstract
ADAR deaminases catalyze adenosine-to-inosine (A-to-I) editing on double-stranded RNA (dsRNA) substrates that regulate an umbrella of biological processes. One of the two catalytically active ADAR enzymes, ADAR1, plays a major role in innate immune responses by suppression of RNA sensing pathways which are orchestrated through the ADAR1-dsRNA-MDA5 axis. Unedited immunogenic dsRNA substrates are potent ligands for the cellular sensor MDA5. Upon activation, MDA5 leads to the induction of interferons and expression of hundreds of interferon-stimulated genes with potent antiviral activity. In this way, ADAR1 acts as a gatekeeper of the RNA sensing pathway by striking a fine balance between innate antiviral responses and prevention of autoimmunity. Reduced editing of immunogenic dsRNA by ADAR1 is strongly linked to the development of common autoimmune and inflammatory diseases. In viral infections, ADAR1 exhibits both antiviral and proviral effects. This is modulated by both editing-dependent and editing-independent functions, such as PKR antagonism. Several A-to-I RNA editing events have been identified in viruses, including in the insidious viral pathogen, SARS-CoV-2 which regulates viral fitness and infectivity, and could play a role in shaping viral evolution. Furthermore, ADAR1 is an attractive target for immuno-oncology therapy. Overexpression of ADAR1 and increased dsRNA editing have been observed in several human cancers. Silencing ADAR1, especially in cancers that are refractory to immune checkpoint inhibitors, is a promising therapeutic strategy for cancer immunotherapy in conjunction with epigenetic therapy. The mechanistic understanding of dsRNA editing by ADAR1 and dsRNA sensing by MDA5 and PKR holds great potential for therapeutic applications. This article is categorized under: RNA Processing > RNA Editing and Modification RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Rohini Datta
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Julia Z Adamska
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Amruta Bhate
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Jin Billy Li
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
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42
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Alkailani MI, Gibbings D. The Regulation and Immune Signature of Retrotransposons in Cancer. Cancers (Basel) 2023; 15:4340. [PMID: 37686616 PMCID: PMC10486412 DOI: 10.3390/cancers15174340] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 08/14/2023] [Accepted: 08/18/2023] [Indexed: 09/10/2023] Open
Abstract
Advances in sequencing technologies and the bioinformatic analysis of big data facilitate the study of jumping genes' activity in the human genome in cancer from a broad perspective. Retrotransposons, which move from one genomic site to another by a copy-and-paste mechanism, are regulated by various molecular pathways that may be disrupted during tumorigenesis. Active retrotransposons can stimulate type I IFN responses. Although accumulated evidence suggests that retrotransposons can induce inflammation, the research investigating the exact mechanism of triggering these responses is ongoing. Understanding these mechanisms could improve the therapeutic management of cancer through the use of retrotransposon-induced inflammation as a tool to instigate immune responses to tumors.
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Affiliation(s)
- Maisa I. Alkailani
- College of Health and Life Sciences, Hamad Bin Khalifa University, Qatar Foundation, Doha P.O. Box 34110, Qatar
| | - Derrick Gibbings
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada;
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43
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Maelfait J, Rehwinkel J. The Z-nucleic acid sensor ZBP1 in health and disease. J Exp Med 2023; 220:e20221156. [PMID: 37450010 PMCID: PMC10347765 DOI: 10.1084/jem.20221156] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/28/2023] [Accepted: 07/05/2023] [Indexed: 07/18/2023] Open
Abstract
Nucleic acid sensing is a central process in the immune system, with far-reaching roles in antiviral defense, autoinflammation, and cancer. Z-DNA binding protein 1 (ZBP1) is a sensor for double-stranded DNA and RNA helices in the unusual left-handed Z conformation termed Z-DNA and Z-RNA. Recent research established ZBP1 as a key upstream regulator of cell death and proinflammatory signaling. Recognition of Z-DNA/RNA by ZBP1 promotes host resistance to viral infection but can also drive detrimental autoinflammation. Additionally, ZBP1 has interesting roles in cancer and other disease settings and is emerging as an attractive target for therapy.
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Affiliation(s)
- Jonathan Maelfait
- VIB-UGent Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Jan Rehwinkel
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
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44
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Cornec A, Poirier EZ. Interplay between RNA interference and transposable elements in mammals. Front Immunol 2023; 14:1212086. [PMID: 37475864 PMCID: PMC10354258 DOI: 10.3389/fimmu.2023.1212086] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 06/20/2023] [Indexed: 07/22/2023] Open
Abstract
RNA interference (RNAi) plays pleiotropic roles in animal cells, from the post-transcriptional control of gene expression via the production of micro-RNAs, to the inhibition of RNA virus infection. We discuss here the role of RNAi in regulating the expression of self RNAs, and particularly transposable elements (TEs), which are genomic sequences capable of influencing gene expression and disrupting genome architecture. Dicer proteins act as the entry point of the RNAi pathway by detecting and degrading RNA of TE origin, ultimately leading to TE silencing. RNAi similarly targets cellular RNAs such as repeats transcribed from centrosomes. Dicer proteins are thus nucleic acid sensors that recognize self RNA in the form of double-stranded RNA, and trigger a silencing RNA interference response.
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Affiliation(s)
| | - Enzo Z. Poirier
- Stem Cell Immunity Team, Institut Curie, PSL Research University, INSERM U932, Paris, France
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45
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Wang CX, Hunt J, Feinstein S, Kim SK, Monjazeb AM. Advances in Radiotherapy Immune Modulation: From Bench-to-Bedside and Back Again. Surg Oncol Clin N Am 2023; 32:617-629. [PMID: 37182996 DOI: 10.1016/j.soc.2023.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Pre-clinical and clinical data clearly demonstrate the immune modulatory effects of radiotherapy (RT) but clinical trials testing RT + immunotherapy have been equivocal. An improved understanding of the immune modulatory effects of RT and how practical parameters of RT delivery (site and number of lesions, dose, fractionation, timing) influence these effects are needed to optimally combine RT with immunotherapy. Additionally, increased exploration of immunotherapy combinations with RT, beyond immune checkpoint inhibitors, are needed. A "bench-to-bedside and back again" approach will improve our understanding of RT immune modulation and allow for the implementation of more effective RT + immunotherapy strategies.
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Affiliation(s)
- Charles X Wang
- UC Davis Health, Department of Radiation Oncology, 4501 X-Street, Sacramento, CA 95817, USA
| | - Jared Hunt
- UC Davis Health, Department of Radiation Oncology, 4501 X-Street, Sacramento, CA 95817, USA
| | - Shera Feinstein
- UC Davis Health, Department of Radiation Oncology, 4501 X-Street, Sacramento, CA 95817, USA
| | - Soo Kyoung Kim
- UC Davis Health, Department of Radiation Oncology, 4501 X-Street, Sacramento, CA 95817, USA
| | - Arta M Monjazeb
- UC Davis Health, Department of Radiation Oncology, 4501 X-Street, Sacramento, CA 95817, USA.
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46
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Enriquez-Gasca R, Gould PA, Tunbak H, Conde L, Herrero J, Chittka A, Beck CR, Gifford R, Rowe HM. Co-option of endogenous retroviruses through genetic escape from TRIM28 repression. Cell Rep 2023; 42:112625. [PMID: 37294634 DOI: 10.1016/j.celrep.2023.112625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 04/04/2023] [Accepted: 05/23/2023] [Indexed: 06/11/2023] Open
Abstract
Endogenous retroviruses (ERVs) have rewired host gene networks. To explore the origins of co-option, we employed an active murine ERV, IAPEz, and an embryonic stem cell (ESC) to neural progenitor cell (NPC) differentiation model. Transcriptional silencing via TRIM28 maps to a 190 bp sequence encoding the intracisternal A-type particle (IAP) signal peptide, which confers retrotransposition activity. A subset of "escapee" IAPs (∼15%) exhibits significant genetic divergence from this sequence. Canonical repressed IAPs succumb to a previously undocumented demarcation by H3K9me3 and H3K27me3 in NPCs. Escapee IAPs, in contrast, evade repression in both cell types, resulting in their transcriptional derepression, particularly in NPCs. We validate the enhancer function of a 47 bp sequence within the U3 region of the long terminal repeat (LTR) and show that escapee IAPs convey an activating effect on nearby neural genes. In sum, co-opted ERVs stem from genetic escapees that have lost vital sequences required for both TRIM28 restriction and autonomous retrotransposition.
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Affiliation(s)
- Rocio Enriquez-Gasca
- Centre for Immunobiology, Blizard Institute, Queen Mary University of London, London E1 2AT, UK.
| | - Poppy A Gould
- Centre for Immunobiology, Blizard Institute, Queen Mary University of London, London E1 2AT, UK
| | - Hale Tunbak
- Centre for Immunobiology, Blizard Institute, Queen Mary University of London, London E1 2AT, UK
| | - Lucia Conde
- Bill Lyons Informatics Centre, UCL Cancer Institute, London WC1E 6DD, UK
| | - Javier Herrero
- Bill Lyons Informatics Centre, UCL Cancer Institute, London WC1E 6DD, UK
| | - Alexandra Chittka
- Centre for Immunobiology, Blizard Institute, Queen Mary University of London, London E1 2AT, UK
| | - Christine R Beck
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, The Jackson Laboratory for Genomic Medicine, Connecticut, JAX CT, Farmington, CT 06032, USA
| | - Robert Gifford
- MRC-University of Glasgow Centre for Virus Research, Glasgow G611QH, UK
| | - Helen M Rowe
- Centre for Immunobiology, Blizard Institute, Queen Mary University of London, London E1 2AT, UK.
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47
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Pecori R, Ren W, Pirmoradian M, Wang X, Liu D, Berglund M, Li W, Tasakis RN, Di Giorgio S, Ye X, Li X, Arnold A, Wüst S, Schneider M, Selvasaravanan KD, Fuell Y, Stafforst T, Amini RM, Sonnevi K, Enblad G, Sander B, Wahlin BE, Wu K, Zhang H, Helm D, Binder M, Papavasiliou FN, Pan-Hammarström Q. ADAR1-mediated RNA editing promotes B cell lymphomagenesis. iScience 2023; 26:106864. [PMID: 37255666 PMCID: PMC10225930 DOI: 10.1016/j.isci.2023.106864] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 02/27/2023] [Accepted: 05/08/2023] [Indexed: 06/01/2023] Open
Abstract
Diffuse large B cell lymphoma (DLBCL) is one of the most common types of aggressive lymphoid malignancies. Here, we explore the contribution of RNA editing to DLBCL pathogenesis. We observed that DNA mutations and RNA editing events are often mutually exclusive, suggesting that tumors can modulate pathway outcomes by altering sequences at either the genomic or the transcriptomic level. RNA editing targets transcripts within known disease-driving pathways such as apoptosis, p53 and NF-κB signaling, as well as the RIG-I-like pathway. In this context, we show that ADAR1-mediated editing within MAVS transcript positively correlates with MAVS protein expression levels, associating with increased interferon/NF-κB signaling and T cell exhaustion. Finally, using targeted RNA base editing tools to restore editing within MAVS 3'UTR in ADAR1-deficient cells, we demonstrate that editing is likely to be causal to an increase in downstream signaling in the absence of activation by canonical nucleic acid receptor sensing.
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Affiliation(s)
- Riccardo Pecori
- Division of Immune Diversity (D150), German Cancer Research Center (DKFZ), Heidelberg, Germany
- Helmholtz Institute for Translational Oncology (HI-TRON), Mainz, Germany
| | - Weicheng Ren
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
- Department of Lymphoma, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
| | - Mohammad Pirmoradian
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
| | - Xianhuo Wang
- Department of Lymphoma, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
| | - Dongbing Liu
- BGI-Shenzhen, Shenzhen, China
- Guangdong Provincial Key Laboratory of Human Disease Genomics, Shenzhen Key Laboratory of Genomics, Shenzhen, China
| | - Mattias Berglund
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Wei Li
- Department of Lymphoma, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
| | - Rafail Nikolaos Tasakis
- Division of Immune Diversity (D150), German Cancer Research Center (DKFZ), Heidelberg, Germany
- Graduate Program in Biosciences, University of Heidelberg, Heidelberg, Germany
| | - Salvatore Di Giorgio
- Division of Immune Diversity (D150), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Xiaofei Ye
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
- Department of Lymphoma, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
| | - Xiaobo Li
- BGI-Shenzhen, Shenzhen, China
- Guangdong Provincial Key Laboratory of Human Disease Genomics, Shenzhen Key Laboratory of Genomics, Shenzhen, China
| | - Annette Arnold
- Division of Immune Diversity (D150), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Sandra Wüst
- Research Group "Dynamics of Early Viral Infection and the Innate Antiviral Response", Division Virus-Associated Carcinogenesis (F170), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Martin Schneider
- Proteomics Core Facility (W120), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | - Yvonne Fuell
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Thorsten Stafforst
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Rose-Marie Amini
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Kristina Sonnevi
- Hematology Unit, Department of Medicine, Huddinge, Karolinska Institutet and Medical Unit Hematology, Karolinska University Hospital, Solna, StockholmSweden
| | - Gunilla Enblad
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Birgitta Sander
- Department of Laboratory Medicine, Karolinska University Hospital, Huddinge, Stockholm, Sweden
| | - Björn Engelbrekt Wahlin
- Hematology Unit, Department of Medicine, Huddinge, Karolinska Institutet and Medical Unit Hematology, Karolinska University Hospital, Solna, StockholmSweden
| | - Kui Wu
- BGI-Shenzhen, Shenzhen, China
- Guangdong Provincial Key Laboratory of Human Disease Genomics, Shenzhen Key Laboratory of Genomics, Shenzhen, China
| | - Huilai Zhang
- Department of Lymphoma, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
| | - Dominic Helm
- Proteomics Core Facility (W120), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Marco Binder
- Research Group "Dynamics of Early Viral Infection and the Innate Antiviral Response", Division Virus-Associated Carcinogenesis (F170), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - F. Nina Papavasiliou
- Division of Immune Diversity (D150), German Cancer Research Center (DKFZ), Heidelberg, Germany
- Graduate Program in Biosciences, University of Heidelberg, Heidelberg, Germany
| | - Qiang Pan-Hammarström
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
- Department of Lymphoma, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
- BGI-Shenzhen, Shenzhen, China
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48
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Straub S, Sampaio NG. Activation of cytosolic RNA sensors by endogenous ligands: roles in disease pathogenesis. Front Immunol 2023; 14:1092790. [PMID: 37292201 PMCID: PMC10244536 DOI: 10.3389/fimmu.2023.1092790] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 05/15/2023] [Indexed: 06/10/2023] Open
Abstract
Early detection of infection is a central and critical component of our innate immune system. Mammalian cells have developed specialized receptors that detect RNA with unusual structures or of foreign origin - a hallmark of many virus infections. Activation of these receptors induces inflammatory responses and an antiviral state. However, it is increasingly appreciated that these RNA sensors can also be activated in the absence of infection, and that this 'self-activation' can be pathogenic and promote disease. Here, we review recent discoveries in sterile activation of the cytosolic innate immune receptors that bind RNA. We focus on new aspects of endogenous ligand recognition uncovered in these studies, and their roles in disease pathogenesis.
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Affiliation(s)
- Sarah Straub
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Molecular and Translational Sciences, School of Clinical Sciences, Monash University, Clayton, VIC, Australia
| | - Natalia G. Sampaio
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Molecular and Translational Sciences, School of Clinical Sciences, Monash University, Clayton, VIC, Australia
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49
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Kleinova R, Rajendra V, Leuchtenberger AF, Lo Giudice C, Vesely C, Kapoor U, Tanzer A, Derdak S, Picardi E, Jantsch MF. The ADAR1 editome reveals drivers of editing-specificity for ADAR1-isoforms. Nucleic Acids Res 2023; 51:4191-4207. [PMID: 37026479 PMCID: PMC10201426 DOI: 10.1093/nar/gkad265] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 03/10/2023] [Accepted: 04/06/2023] [Indexed: 04/08/2023] Open
Abstract
Adenosine deaminase acting on RNA ADAR1 promotes A-to-I conversion in double-stranded and structured RNAs. ADAR1 has two isoforms transcribed from different promoters: cytoplasmic ADAR1p150 is interferon-inducible while ADAR1p110 is constitutively expressed and primarily localized in the nucleus. Mutations in ADAR1 cause Aicardi - Goutières syndrome (AGS), a severe autoinflammatory disease associated with aberrant IFN production. In mice, deletion of ADAR1 or the p150 isoform leads to embryonic lethality driven by overexpression of interferon-stimulated genes. This phenotype is rescued by deletion of the cytoplasmic dsRNA-sensor MDA5 indicating that the p150 isoform is indispensable and cannot be rescued by ADAR1p110. Nevertheless, editing sites uniquely targeted by ADAR1p150 remain elusive. Here, by transfection of ADAR1 isoforms into ADAR-less mouse cells we detect isoform-specific editing patterns. Using mutated ADAR variants, we test how intracellular localization and the presence of a Z-DNA binding domain-α affect editing preferences. These data show that ZBDα only minimally contributes to p150 editing-specificity while isoform-specific editing is primarily directed by the intracellular localization of ADAR1 isoforms. Our study is complemented by RIP-seq on human cells ectopically expressing tagged-ADAR1 isoforms. Both datasets reveal enrichment of intronic editing and binding by ADAR1p110 while ADAR1p150 preferentially binds and edits 3'UTRs.
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Affiliation(s)
- Renata Kleinova
- Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090 Vienna, Austria
| | - Vinod Rajendra
- Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090 Vienna, Austria
| | - Alina F Leuchtenberger
- Center for Integrative Bioinformatics Vienna (CIBIV) Max Perutz Labs, University of Vienna and Medical University of Vienna, Campus Vienna Biocenter 5, A-1030 Vienna, Austria
| | - Claudio Lo Giudice
- Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, University Campus “Ernesto Quagliariello”, Via Orabona 4, Bari, Italy
| | - Cornelia Vesely
- Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090 Vienna, Austria
| | - Utkarsh Kapoor
- Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090 Vienna, Austria
| | - Andrea Tanzer
- Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090 Vienna, Austria
| | - Sophia Derdak
- Core Facilities Medical University of Vienna, Spitalgasse 23, A-1090 Vienna, Austria
| | - Ernesto Picardi
- Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, University Campus “Ernesto Quagliariello”, Via Orabona 4, Bari, Italy
- Institute of Biomembranes and Bioenergetics (IBBE), National Research Council (CNR), Via Amendola 122, Bari, Italy
| | - Michael F Jantsch
- Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Medical University of Vienna, Schwarzspanierstrasse 17, A-1090 Vienna, Austria
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50
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Sun S, Hong J, You E, Tsanov KM, Chacon-Barahona J, Gioacchino AD, Hoyos D, Li H, Jiang H, Ly H, Marhon S, Murali R, Chanda P, Karacay A, Vabret N, De Carvalho DD, LaCava J, Lowe SW, Ting DT, Iacobuzio-Donahue CA, Solovyov A, Greenbaum BD. Cancer cells co-evolve with retrotransposons to mitigate viral mimicry. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.19.541456. [PMID: 37292765 PMCID: PMC10245669 DOI: 10.1101/2023.05.19.541456] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Overexpression of repetitive elements is an emerging hallmark of human cancers 1 . Diverse repeats can mimic viruses by replicating within the cancer genome through retrotransposition, or presenting pathogen-associated molecular patterns (PAMPs) to the pattern recognition receptors (PRRs) of the innate immune system 2-5 . Yet, how specific repeats affect tumor evolution and shape the tumor immune microenvironment (TME) in a pro- or anti-tumorigenic manner remains poorly defined. Here, we integrate whole genome and total transcriptome data from a unique autopsy cohort of multiregional samples collected in pancreatic ductal adenocarcinoma (PDAC) patients, into a comprehensive evolutionary analysis. We find that more recently evolved S hort I nterspersed N uclear E lements (SINE), a family of retrotransposable repeats, are more likely to form immunostimulatory double-strand RNAs (dsRNAs). Consequently, younger SINEs are strongly co-regulated with RIG-I like receptor associated type-I interferon genes but anti-correlated with pro-tumorigenic macrophage infiltration. We discover that immunostimulatory SINE expression in tumors is regulated by either L ong I nterspersed N uclear E lements 1 (LINE1/L1) mobility or ADAR1 activity in a TP53 mutation dependent manner. Moreover, L1 retrotransposition activity tracks with tumor evolution and is associated with TP53 mutation status. Altogether, our results suggest pancreatic tumors actively evolve to modulate immunogenic SINE stress and induce pro-tumorigenic inflammation. Our integrative, evolutionary analysis therefore illustrates, for the first time, how dark matter genomic repeats enable tumors to co-evolve with the TME by actively regulating viral mimicry to their selective advantage.
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