1
|
Zhou Y, Song HM. Type I interferon pathway in pediatric systemic lupus erythematosus. World J Pediatr 2024; 20:653-668. [PMID: 38914753 PMCID: PMC11269505 DOI: 10.1007/s12519-024-00811-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 03/27/2024] [Indexed: 06/26/2024]
Abstract
BACKGROUND The role of type I interferon (IFN-I) signaling in systemic lupus erythematosus (SLE) has been well established. However, unanswered questions remain regarding the applicability of these findings to pediatric-onset SLE. The aim of this review is to provide an overview of the novel discoveries on IFN-I signaling in pediatric-onset SLE. DATA SOURCES A literature search was conducted in the PubMed database using the following keywords: "pediatric systemic lupus erythematosus" and "type I interferon". RESULTS IFN-I signaling is increased in pediatric SLE, largely due to the presence of plasmacytoid dendritic cells and pathways such as cyclic GMP-AMP synthase-stimulator of interferon genes-TANK-binding kinase 1 and Toll-like receptor (TLR)4/TLR9. Neutrophil extracellular traps and oxidative DNA damage further stimulate IFN-I production. Genetic variants in IFN-I-related genes, such as IFN-regulatory factor 5 and tyrosine kinase 2, are linked to SLE susceptibility in pediatric patients. In addition, type I interferonopathies, characterized by sustained IFN-I activation, can mimic SLE symptoms and are thus important to distinguish. Studies on interferonopathies also contribute to exploring the pathogenesis of SLE. Measuring IFN-I activation is crucial for SLE diagnosis and stratification. Both IFN-stimulated gene expression and serum IFN-α2 levels are common indicators. Flow cytometry markers such as CD169 and galectin-9 are promising alternatives. Anti-IFN therapies, such as sifalimumab and anifrolumab, show promise in adult patients with SLE, but their efficacy in pediatric patients requires further investigation. Janus kinase inhibitors are another treatment option for severe pediatric SLE patients. CONCLUSIONS This review presents an overview of the IFN-I pathway in pediatric SLE. Understanding the intricate relationship between IFN-I and pediatric SLE may help to identify potential diagnostic markers and targeted therapies, paving the way for improved patient care and outcomes.
Collapse
Affiliation(s)
- Yu Zhou
- Department of Pediatrics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Beijing, China
| | - Hong-Mei Song
- Department of Pediatrics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.
- State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Beijing, China.
| |
Collapse
|
2
|
Solotchi M, Patel SS. Proofreading mechanisms of the innate immune receptor RIG-I: distinguishing self and viral RNA. Biochem Soc Trans 2024; 52:1131-1148. [PMID: 38884803 PMCID: PMC11346460 DOI: 10.1042/bst20230724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2024] [Revised: 06/02/2024] [Accepted: 06/04/2024] [Indexed: 06/18/2024]
Abstract
The RIG-I-like receptors (RLRs), comprising retinoic acid-inducible gene I (RIG-I), melanoma differentiation-associated gene 5 (MDA5), and laboratory of genetics and physiology 2 (LGP2), are pattern recognition receptors belonging to the DExD/H-box RNA helicase family of proteins. RLRs detect viral RNAs in the cytoplasm and respond by initiating a robust antiviral response that up-regulates interferon and cytokine production. RIG-I and MDA5 complement each other by recognizing different RNA features, and LGP2 regulates their activation. RIG-I's multilayered RNA recognition and proofreading mechanisms ensure accurate viral RNA detection while averting harmful responses to host RNAs. RIG-I's C-terminal domain targets 5'-triphosphate double-stranded RNA (dsRNA) blunt ends, while an intrinsic gating mechanism prevents the helicase domains from non-specifically engaging with host RNAs. The ATPase and RNA translocation activity of RIG-I adds another layer of selectivity by minimizing the lifetime of RIG-I on non-specific RNAs, preventing off-target activation. The versatility of RIG-I's ATPase function also amplifies downstream signaling by enhancing the signaling domain (CARDs) exposure on 5'-triphosphate dsRNA and promoting oligomerization. In this review, we offer an in-depth understanding of the mechanisms RIG-I uses to facilitate viral RNA sensing and regulate downstream activation of the immune system.
Collapse
Affiliation(s)
- Mihai Solotchi
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, U.S.A
- Graduate School of Biomedical Sciences, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, U.S.A
| | - Smita S. Patel
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, U.S.A
| |
Collapse
|
3
|
Yoneyama M, Kato H, Fujita T. Physiological functions of RIG-I-like receptors. Immunity 2024; 57:731-751. [PMID: 38599168 DOI: 10.1016/j.immuni.2024.03.003] [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: 01/20/2024] [Revised: 02/19/2024] [Accepted: 03/04/2024] [Indexed: 04/12/2024]
Abstract
RIG-I-like receptors (RLRs) are crucial for pathogen detection and triggering immune responses and have immense physiological importance. In this review, we first summarize the interferon system and innate immunity, which constitute primary and secondary responses. Next, the molecular structure of RLRs and the mechanism of sensing non-self RNA are described. Usually, self RNA is refractory to the RLR; however, there are underlying host mechanisms that prevent immune reactions. Studies have revealed that the regulatory mechanisms of RLRs involve covalent molecular modifications, association with regulatory factors, and subcellular localization. Viruses have evolved to acquire antagonistic RLR functions to escape the host immune reactions. Finally, the pathologies caused by the malfunction of RLR signaling are described.
Collapse
Affiliation(s)
- Mitsutoshi Yoneyama
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, Chiba, Japan; Division of Pandemic and Post-disaster Infectious Diseases, Research Institute of Disaster Medicine, Chiba University, Chiba, Japan
| | - Hiroki Kato
- Institute of Cardiovascular Immunology, Medical Faculty, University Hospital Bonn, University of Bonn, Bonn, Germany
| | - Takashi Fujita
- Institute of Cardiovascular Immunology, Medical Faculty, University Hospital Bonn, University of Bonn, Bonn, Germany; Laboratory of Regulatory Information, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.
| |
Collapse
|
4
|
Lee KY, Craig C, Patel SS. Unraveling blunt-end RNA binding and ATPase-driven translocation activities of the RIG-I family helicase LGP2. Nucleic Acids Res 2024; 52:355-369. [PMID: 38015453 PMCID: PMC10783506 DOI: 10.1093/nar/gkad1106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/28/2023] [Accepted: 11/01/2023] [Indexed: 11/29/2023] Open
Abstract
The RIG-I family helicases, comprising RIG-I, MDA5 and LGP2, are cytoplasmic RNA sensors that trigger an antiviral immune response by specifically recognizing foreign RNAs. While LGP2 lacks the signaling domain necessary for immune activation, it plays a vital role in regulating the RIG-I/MDA5 signaling pathway. In this study, we investigate the mechanisms underlying this regulation by examining the oligomeric state, RNA binding specificity, and translocation activity of human LGP2 and the impact of ATPase activity. We show that LGP2, like RIG-I, prefers binding blunt-ended double-stranded (ds) RNAs over internal dsRNA regions or RNA overhangs and associates with blunt-ends faster than with overhangs. Unlike RIG-I, a 5'-triphosphate (5'ppp), Cap0, or Cap1 RNA-end does not influence LGP2's RNA binding affinity. LGP2 hydrolyzes ATP in the presence of RNA but at a 5-10 fold slower rate than RIG-I. Nevertheless, LGP2 uses its ATPase activity to translocate and displace biotin-streptavidin interactions. This activity is significantly hindered by a methylated RNA patch, particularly on the 3'-strand, suggesting a 3'-strand tracking mechanism like RIG-I. The preference of LGP2 for blunt-end RNA binding, its insensitivity to Cap0/Cap1 modification, and its translocation/protein displacement ability have substantial implications for how LGP2 regulates the RNA sensing process by MDA5/RIG-I.
Collapse
Affiliation(s)
- Kuan-Ying Lee
- Department of Biochemistry and Molecular Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
- Graduate School of Biomedical Sciences at the Robert Wood Johnson Medical School of Rutgers University, 08854, USA
| | - Candice Craig
- Department of Biochemistry and Molecular Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
- Graduate School of Biomedical Sciences at the Robert Wood Johnson Medical School of Rutgers University, 08854, USA
| | - Smita S Patel
- Department of Biochemistry and Molecular Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| |
Collapse
|
5
|
Susanto TT, Hung V, Levine AG, Kerr CH, Yoo Y, Chen Y, Oses-Prieto JA, Fromm L, Fujii K, Wernig M, Burlingame AL, Ruggero D, Barna M. RAPIDASH: A tag-free enrichment of ribosome-associated proteins reveals compositional dynamics in embryonic tissues and stimulated macrophages. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.07.570613. [PMID: 38106052 PMCID: PMC10723405 DOI: 10.1101/2023.12.07.570613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Ribosomes are emerging as direct regulators of gene expression, with ribosome-associated proteins (RAPs) allowing ribosomes to modulate translational control. However, a lack of technologies to enrich RAPs across many sample types has prevented systematic analysis of RAP number, dynamics, and functions. Here, we have developed a label-free methodology called RAPIDASH to enrich ribosomes and RAPs from any sample. We applied RAPIDASH to mouse embryonic tissues and identified hundreds of potential RAPs, including DHX30 and LLPH, two forebrain RAPs important for neurodevelopment. We identified a critical role of LLPH in neural development that is linked to the translation of genes with long coding sequences. Finally, we characterized ribosome composition remodeling during immune activation and observed extensive changes post-stimulation. RAPIDASH has therefore enabled the discovery of RAPs ranging from those with neuroregulatory functions to those activated by immune stimuli, thereby providing critical insights into how ribosomes are remodeled.
Collapse
Affiliation(s)
- Teodorus Theo Susanto
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Victoria Hung
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Andrew G Levine
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, USA
- Department of Urology, University of California, San Francisco, San Francisco, CA, USA
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Craig H Kerr
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Yongjin Yoo
- Institute for Stem Cell Biology and Regenerative Medicine and Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Yuxiang Chen
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Juan A Oses-Prieto
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158, USA
| | - Lisa Fromm
- Department of Urology, University of California, San Francisco, San Francisco, CA, USA
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA
| | - Kotaro Fujii
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Marius Wernig
- Institute for Stem Cell Biology and Regenerative Medicine and Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alma L Burlingame
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158, USA
| | - Davide Ruggero
- Department of Urology, University of California, San Francisco, San Francisco, CA, USA
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA
| | - Maria Barna
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| |
Collapse
|
6
|
Sikorska J, Hou Y, Chiurazzi P, Siu T, Baltus GA, Sheth P, McLaren D, Truong Q, Parish C, Wyss D. Characterization of RNA driven structural changes in full length RIG-I leading to its agonism or antagonism. Nucleic Acids Res 2023; 51:9356-9368. [PMID: 37486777 PMCID: PMC10516622 DOI: 10.1093/nar/gkad606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 06/30/2023] [Accepted: 07/20/2023] [Indexed: 07/26/2023] Open
Abstract
RIG-I (retinoic acid inducible gene-I) can sense subtle differences between endogenous and viral RNA in the cytoplasm, triggering an anti-viral immune response through induction of type I interferons (IFN) and other inflammatory mediators. Multiple crystal and cryo-EM structures of RIG-I suggested a mechanism in which the C-terminal domain (CTD) is responsible for the recognition of viral RNA with a 5'-triphoshate modification, while the CARD domains serve as a trigger for downstream signaling, leading to the induction of type I IFN. However, to date contradicting conclusions have been reached around the role of ATP in the mechanism of the CARD domains ejection from RIG-I's autoinhibited state. Here we present an application of NMR spectroscopy to investigate changes induced by the binding of 5'-triphosphate and 5'-OH dsRNA, both in the presence and absence of nucleotides, to full length RIG-I with all its methionine residues selectively labeled (Met-[ϵ-13CH3]). With this approach we were able to identify residues on the CTD, helicase domain, and CARDs that served as probes to sense RNA-induced conformational changes in those respective regions. Our results were analyzed in the context of either agonistic or antagonistic RNAs, by and large supporting a mechanism proposed by the Pyle Lab in which CARD release is primarily dependent on the RNA binding event.
Collapse
Affiliation(s)
| | - Yan Hou
- Merck & Co., Inc., Rahway, NJ, USA
| | | | - Tony Siu
- Merck & Co., Inc., Rahway, NJ, USA
| | | | | | | | | | | | | |
Collapse
|
7
|
Zheng J, Shi W, Yang Z, Chen J, Qi A, Yang Y, Deng Y, Yang D, Song N, Song B, Luo D. RIG-I-like receptors: Molecular mechanism of activation and signaling. Adv Immunol 2023; 158:1-74. [PMID: 37453753 DOI: 10.1016/bs.ai.2023.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
During RNA viral infection, RIG-I-like receptors (RLRs) recognize the intracellular pathogenic RNA species derived from viral replication and activate antiviral innate immune response by stimulating type 1 interferon expression. Three RLR members, namely, RIG-I, MDA5, and LGP2 are homologous and belong to a subgroup of superfamily 2 Helicase/ATPase that is preferably activated by double-stranded RNA. RLRs are significantly different in gene architecture, RNA ligand preference, activation, and molecular functions. As switchable macromolecular sensors, RLRs' activities are tightly regulated by RNA ligands, ATP, posttranslational modifications, and cellular cofactors. We provide a comprehensive review of the structure and function of the RLRs and summarize the molecular understanding of sensing and signaling events during the RLR activation process. The key roles RLR signaling play in both anti-infection and immune disease conditions highlight the therapeutic potential in targeting this important molecular pathway.
Collapse
Affiliation(s)
- Jie Zheng
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, China; Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
| | - Wenjia Shi
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Ziqun Yang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Jin Chen
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Ao Qi
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, China; Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Yulin Yang
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, China; Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Ying Deng
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Dongyuan Yang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Ning Song
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Bin Song
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore; NTU Institute of Structural Biology, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
8
|
Miyamoto M, Himeda T, Ishihara K, Okuwa T, Kobayashi D, Nameta M, Karasawa Y, Chunhaphinyokul B, Yoshida Y, Tanaka N, Higuchi M, Komuro A. Theilovirus 3C Protease Cleaves the C-Terminal Domain of the Innate Immune RNA Sensor, Melanoma Differentiation-Associated Gene 5, and Impairs Double-Stranded RNA-Mediated IFN Response. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:335-347. [PMID: 36525065 DOI: 10.4049/jimmunol.2200565] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 11/09/2022] [Indexed: 01/04/2023]
Abstract
Melanoma differentiation-associated gene 5 (MDA5), a member of the retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs), has pivotal roles in innate immune responses against many positive-stranded RNA viruses, including picornavirus and coronavirus. Upon engagement with dsRNA derived from viral infection, MDA5 initiates coordinated signal transduction leading to type I IFN induction to restrict viral replication. In this study, we describe a targeted cleavage events of MDA5 by the 3C protease from Theilovirus. Upon ectopic expression of theilovirus 3C protease from Saffold virus or Theiler's murine encephalomyelitis virus but not encephalomyocarditis virus, fragments of cleaved MDA5 were observed in a dose-dependent manner. When enzymatically inactive Theilovirus 3C protease was expressed, MDA5 cleavage was completely abrogated. Mass spectrometric analysis identified two cleavage sites at the C terminus of MDA5, cleaving off one of the RNA-binding domains. The same cleavage pattern was observed during Theilovirus infection. The cleavage of MDA5 by Theilovirus protease impaired ATP hydrolysis, RNA binding, and filament assembly on RNA, resulting in dysfunction of MDA5 as an innate immune RNA sensor for IFN induction. Furthermore, the cleavage-resistant MDA5 mutant against the 3C protease showed an enhanced IFN response during Saffold virus infection, indicating that Theilovirus has a strategy to circumvent the antiviral immune response by cleaving MDA5 using 3C protease. In summary, these data suggest MDA5 cleavage by 3C protease as a novel immune evasive strategy of Theilovirus.
Collapse
Affiliation(s)
- Masahiko Miyamoto
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan
| | - Toshiki Himeda
- Department of Microbiology, Kanazawa Medical University School of Medicine, Ishikawa, Japan
| | - Kazuki Ishihara
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan
| | - Takako Okuwa
- Department of Microbiology, Kanazawa Medical University School of Medicine, Ishikawa, Japan
| | - Daiki Kobayashi
- Omics Unit, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Masaaki Nameta
- Electron Microscope Core Facility, Niigata University, Niigata, Japan
| | - Yu Karasawa
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan
| | - Benyapa Chunhaphinyokul
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan
| | - Yutaka Yoshida
- Department of Structural Pathology, Kidney Research Center, Niigata University, Niigata, Japan; and
| | - Nobuyuki Tanaka
- Division of Tumor Immunology, Miyagi Cancer Center Research Institute, Medeshima-Shiode, Natori, Miyagi, Japan
| | - Masaya Higuchi
- Department of Microbiology, Kanazawa Medical University School of Medicine, Ishikawa, Japan
| | - Akihiko Komuro
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan
| |
Collapse
|
9
|
Wang W, Pyle AM. The RIG-I receptor adopts two different conformations for distinguishing host from viral RNA ligands. Mol Cell 2022; 82:4131-4144.e6. [DOI: 10.1016/j.molcel.2022.09.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 08/09/2022] [Accepted: 09/28/2022] [Indexed: 11/06/2022]
|
10
|
Schweibenz BD, Devarkar SC, Solotchi M, Craig C, Zheng J, Pascal BD, Gokhale S, Xie P, Griffin PR, Patel SS. The intrinsically disordered CARDs-Helicase linker in RIG-I is a molecular gate for RNA proofreading. EMBO J 2022; 41:e109782. [PMID: 35437807 PMCID: PMC9108607 DOI: 10.15252/embj.2021109782] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 03/28/2022] [Accepted: 04/04/2022] [Indexed: 01/22/2023] Open
Abstract
The innate immune receptor RIG-I provides a first line of defense against viral infections. Viral RNAs are recognized by RIG-I's C-terminal domain (CTD), but the RNA must engage the helicase domain to release the signaling CARD (Caspase Activation and Recruitment Domain) domains from their autoinhibitory CARD2:Hel2i interactions. Because the helicase itself lacks RNA specificity, mechanisms to proofread RNAs entering the helicase domain must exist. Although such mechanisms would be crucial in preventing aberrant immune responses by non-specific RNAs, they remain largely uncharacterized to date. This study reveals a previously unknown proofreading mechanism through which RIG-I ensures that the helicase engages RNAs explicitly recognized by the CTD. A crucial part of this mechanism involves the intrinsically disordered CARDs-Helicase Linker (CHL), which connects the CARDs to the helicase subdomain Hel1. CHL uses its negatively charged regions to antagonize incoming RNAs electrostatically. In addition to this RNA gating function, CHL is essential for stabilization of the CARD2:Hel2i interface. Overall, we uncover that the CHL and CARD2:Hel2i interface work together to establish a tunable gating mechanism that allows CTD-chosen RNAs to bind the helicase domain, while at the same time blocking non-specific RNAs. These findings also indicate that CHL could represent a novel target for RIG-I-based therapeutics.
Collapse
Affiliation(s)
- Brandon D Schweibenz
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA.,Graduate Program in Biochemistry, Rutgers University, Piscataway, NJ, USA
| | - Swapnil C Devarkar
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA.,Graduate Program in Biochemistry, Rutgers University, Piscataway, NJ, USA
| | - Mihai Solotchi
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA.,Cell and Development Biology, Rutgers University, Piscataway, NJ, USA
| | - Candice Craig
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA.,Graduate Program in Biochemistry, Rutgers University, Piscataway, NJ, USA
| | - Jie Zheng
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Bruce D Pascal
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Samantha Gokhale
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, USA.,Cellular and Molecular Pharmacology, Rutgers University, Piscataway, NJ, USA
| | - Ping Xie
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, USA.,Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Patrick R Griffin
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA.,Department of Integrative Structural and Computational Biology, Jupiter, FL, USA
| | - Smita S Patel
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA.,Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| |
Collapse
|
11
|
Venus S, Jankowsky E. Measuring the impact of cofactors on RNA helicase activities. Methods 2022; 204:376-385. [PMID: 35429628 PMCID: PMC9306305 DOI: 10.1016/j.ymeth.2022.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/03/2022] [Accepted: 04/12/2022] [Indexed: 12/25/2022] Open
Abstract
RNA helicases are the largest class of enzymes in eukaryotic RNA metabolism. In cells, protein cofactors regulate RNA helicase functions and impact biochemical helicase activities. Understanding how cofactors affect enzymatic activities of RNA helicases is thus critical for delineating physical roles and regulation of RNA helicases in cells. Here, we discuss approaches and conceptual considerations for the design of experiments to interrogate cofactor effects on RNA helicase activities in vitro. We outline the mechanistic frame for helicase reactions, discuss optimization of experimental setup and reaction parameters for measuring cofactor effects on RNA helicase activities, and provide basic guides to data analysis and interpretation. The described approaches are also instructive for determining the impact of small molecule inhibitors of RNA helicases.
Collapse
|
12
|
Li K, Zheng J, Wirawan M, Trinh NM, Fedorova O, Griffin PR, Pyle AM, Luo D. Insights into the structure and RNA-binding specificity of Caenorhabditis elegans Dicer-related helicase 3 (DRH-3). Nucleic Acids Res 2021; 49:9978-9991. [PMID: 34403472 PMCID: PMC8464030 DOI: 10.1093/nar/gkab712] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 07/31/2021] [Accepted: 08/03/2021] [Indexed: 12/17/2022] Open
Abstract
DRH-3 is critically involved in germline development and RNA interference (RNAi) facilitated chromosome segregation via the 22G-siRNA pathway in Caenorhabditis elegans. DRH-3 has similar domain architecture to RIG-I-like receptors (RLRs) and belongs to the RIG-I-like RNA helicase family. The molecular understanding of DRH-3 and its function in endogenous RNAi pathways remains elusive. In this study, we solved the crystal structures of the DRH-3 N-terminal domain (NTD) and the C-terminal domains (CTDs) in complex with 5'-triphosphorylated RNAs. The NTD of DRH-3 adopts a distinct fold of tandem caspase activation and recruitment domains (CARDs) structurally similar to the CARDs of RIG-I and MDA5, suggesting a signaling function in the endogenous RNAi biogenesis. The CTD preferentially recognizes 5'-triphosphorylated double-stranded RNAs bearing the typical features of secondary siRNA transcripts. The full-length DRH-3 displays unique structural dynamics upon binding to RNA duplexes that differ from RIG-I or MDA5. These features of DRH-3 showcase the evolutionary divergence of the Dicer and RLR family of helicases.
Collapse
Affiliation(s)
- Kuohan Li
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive 636921, Singapore.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive 637551, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive 636921, Singapore
| | - Jie Zheng
- The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Melissa Wirawan
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive 636921, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive 636921, Singapore
| | - Nguyen Mai Trinh
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive 636921, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive 636921, Singapore
| | - Olga Fedorova
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | | | - Anna M Pyle
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive 636921, Singapore.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive 637551, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive 636921, Singapore
| |
Collapse
|
13
|
Thoresen D, Wang W, Galls D, Guo R, Xu L, Pyle AM. The molecular mechanism of RIG-I activation and signaling. Immunol Rev 2021; 304:154-168. [PMID: 34514601 PMCID: PMC9293153 DOI: 10.1111/imr.13022] [Citation(s) in RCA: 99] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 08/10/2021] [Accepted: 08/17/2021] [Indexed: 12/25/2022]
Abstract
RIG‐I is our first line of defense against RNA viruses, serving as a pattern recognition receptor that identifies molecular features common among dsRNA and ssRNA viral pathogens. RIG‐I is maintained in an inactive conformation as it samples the cellular space for pathogenic RNAs. Upon encounter with the triphosphorylated terminus of blunt‐ended viral RNA duplexes, the receptor changes conformation and releases a pair of signaling domains (CARDs) that are selectively modified and interact with an adapter protein (MAVS), thereby triggering a signaling cascade that stimulates transcription of interferons. Here, we describe the structural determinants for specific RIG‐I activation by viral RNA, and we describe the strategies by which RIG‐I remains inactivated in the presence of host RNAs. From the initial RNA triggering event to the final stages of interferon expression, we describe the experimental evidence underpinning our working knowledge of RIG‐I signaling. We draw parallels with behavior of related proteins MDA5 and LGP2, describing evolutionary implications of their collective surveillance of the cell. We conclude by describing the cell biology and immunological investigations that will be needed to accurately describe the role of RIG‐I in innate immunity and to provide the necessary foundation for pharmacological manipulation of this important receptor.
Collapse
Affiliation(s)
- Daniel Thoresen
- Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Wenshuai Wang
- Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Drew Galls
- Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Rong Guo
- Chemistry, Yale University, New Haven, CT, USA
| | - Ling Xu
- Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Anna Marie Pyle
- Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.,Chemistry, Yale University, New Haven, CT, USA.,Howard Hughes Medical Institute, Yale University, New Haven, CT, USA
| |
Collapse
|
14
|
Steinberg J, Wadenpohl T, Jung S. The Endogenous RIG-I Ligand Is Generated in Influenza A-Virus Infected Cells. Viruses 2021; 13:1564. [PMID: 34452429 PMCID: PMC8402674 DOI: 10.3390/v13081564] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/03/2021] [Accepted: 08/06/2021] [Indexed: 12/16/2022] Open
Abstract
As a result of a viral infection, viral genomes are not only recognized by RIG-I, but also lead to the activation of RNase L, which cleaves cellular RNA to generate the endogenous RIG-I ligand (eRL). The eRL was previously identified as a specific sequence derived from the internal transcribed spacer region 2, which bears a 2'3' cyclic phosphate instead of the common 5' triphosphate. By now, the generation of the eRL and its immunostimulatory effect were shown both in vitro and in reporter systems. In this work, we aimed to elucidate whether the eRL is also generated in Influenza A (IAV) and vesicular stomatitis virus (VSV) infected cells. RNA was extracted from virus-infected cells and used for immunostimulations as well as specific PCR-strategies to detect eRL cleavage. We show that the eRL is generated in IAV infected HEK293 cells, but we could not detect specific eRL fragments in VSV infected cells. Further, RIG-I mediated IFN-response depends not only on viral genomes but also on the eRL, as immunostimulatory properties remain present under 5'triphosphate degrading conditions. In summary, we prove the IAV infection induced eRL generation in HEK293 cells, amplifying the innate immune response.
Collapse
Affiliation(s)
| | | | - Stephanie Jung
- Institute of Cardiovascular Immunology, University Hospital Bonn, University of Bonn, 53127 Bonn, Germany; (J.S.); (T.W.)
| |
Collapse
|
15
|
de Oliveira Mann CC, Hornung V. Molecular mechanisms of nonself nucleic acid recognition by the innate immune system. Eur J Immunol 2021; 51:1897-1910. [PMID: 34138462 DOI: 10.1002/eji.202049116] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/13/2021] [Accepted: 06/15/2021] [Indexed: 12/24/2022]
Abstract
Nucleic acids (NAs) represent one of the most important classes of molecules recognized by the innate immune system. However, NAs are not limited to pathogens, but are also present within the host. As such, the immune system has evolved an elaborate set of pathogen recognition receptors (PRRs) that employ various strategies to recognize distinct types of NAs, while reliably distinguishing between self and nonself. The here-employed strategies encompass the positioning of NA-sensing PRRs in certain subcellular compartments that potentially come in contact with pathogens but not host NAs, the existence of counterregulatory measures that keep endogenous NAs below a certain threshold, and also the specific identification of certain nonself patterns. Here, we review recent advances in the molecular mechanisms of NA recognition by TLRs, RLRs, and the cGAS-STING axis. We highlight the differences in NA-PRR interfaces that confer specificity and selectivity toward an NA ligand, as well as the NA-dependent induced conformational changes required for signal transduction.
Collapse
Affiliation(s)
| | - Veit Hornung
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| |
Collapse
|
16
|
Guo G, Gao M, Gao X, Zhu B, Huang J, Tu X, Kim W, Zhao F, Zhou Q, Zhu S, Wu Z, Yan Y, Zhang Y, Zeng X, Zhu Q, Yin P, Luo K, Sun J, Deng M, Lou Z. Reciprocal regulation of RIG-I and XRCC4 connects DNA repair with RIG-I immune signaling. Nat Commun 2021; 12:2187. [PMID: 33846346 PMCID: PMC8041803 DOI: 10.1038/s41467-021-22484-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 03/16/2021] [Indexed: 02/08/2023] Open
Abstract
The RNA-sensing pathway contributes to type I interferon (IFN) production induced by DNA damaging agents. However, the potential involvement of RNA sensors in DNA repair is unknown. Here, we found that retinoic acid-inducible gene I (RIG-I), a key cytosolic RNA sensor that recognizes RNA virus and initiates the MAVS-IRF3-type I IFN signaling cascade, is recruited to double-stranded breaks (DSBs) and suppresses non-homologous end joining (NHEJ). Mechanistically, RIG-I interacts with XRCC4, and the RIG-I/XRCC4 interaction impedes the formation of XRCC4/LIG4/XLF complex at DSBs. High expression of RIG-I compromises DNA repair and sensitizes cancer cells to irradiation treatment. In contrast, depletion of RIG-I renders cells resistant to irradiation in vitro and in vivo. In addition, this mechanism suggests a protective role of RIG-I in hindering retrovirus integration into the host genome by suppressing the NHEJ pathway. Reciprocally, XRCC4, while suppressed for its DNA repair function, has a critical role in RIG-I immune signaling through RIG-I interaction. XRCC4 promotes RIG-I signaling by enhancing oligomerization and ubiquitination of RIG-I, thereby suppressing RNA virus replication in host cells. In vivo, silencing XRCC4 in mouse lung promotes influenza virus replication in mice and these mice display faster body weight loss, poorer survival, and a greater degree of lung injury caused by influenza virus infection. This reciprocal regulation of RIG-I and XRCC4 reveals a new function of RIG-I in suppressing DNA repair and virus integration into the host genome, and meanwhile endues XRCC4 with a crucial role in potentiating innate immune response, thereby helping host to prevail in the battle against virus.
Collapse
Affiliation(s)
- Guijie Guo
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Ming Gao
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Xiaochen Gao
- Thoracic Diseases Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
- Department of Immunology, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - Bibo Zhu
- Thoracic Diseases Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
- Department of Immunology, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - Jinzhou Huang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Xinyi Tu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Wootae Kim
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Fei Zhao
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Qin Zhou
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Shouhai Zhu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Zheming Wu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Yuanliang Yan
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Yong Zhang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Xiangyu Zeng
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Qian Zhu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Ping Yin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Kuntian Luo
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Jie Sun
- Thoracic Diseases Research Unit, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
- Department of Immunology, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - Min Deng
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA.
- Department of Oncology, Mayo Clinic, Rochester, MN, USA.
| | - Zhenkun Lou
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA.
- Department of Oncology, Mayo Clinic, Rochester, MN, USA.
| |
Collapse
|
17
|
Onomoto K, Onoguchi K, Yoneyama M. Regulation of RIG-I-like receptor-mediated signaling: interaction between host and viral factors. Cell Mol Immunol 2021; 18:539-555. [PMID: 33462384 PMCID: PMC7812568 DOI: 10.1038/s41423-020-00602-7] [Citation(s) in RCA: 178] [Impact Index Per Article: 59.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/17/2020] [Indexed: 01/31/2023] Open
Abstract
Retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) are RNA sensor molecules that play essential roles in innate antiviral immunity. Among the three RLRs encoded by the human genome, RIG-I and melanoma differentiation-associated gene 5, which contain N-terminal caspase recruitment domains, are activated upon the detection of viral RNAs in the cytoplasm of virus-infected cells. Activated RLRs induce downstream signaling via their interactions with mitochondrial antiviral signaling proteins and activate the production of type I and III interferons and inflammatory cytokines. Recent studies have shown that RLR-mediated signaling is regulated by interactions with endogenous RNAs and host proteins, such as those involved in stress responses and posttranslational modifications. Since RLR-mediated cytokine production is also involved in the regulation of acquired immunity, the deregulation of RLR-mediated signaling is associated with autoimmune and autoinflammatory disorders. Moreover, RLR-mediated signaling might be involved in the aberrant cytokine production observed in coronavirus disease 2019. Since the discovery of RLRs in 2004, significant progress has been made in understanding the mechanisms underlying the activation and regulation of RLR-mediated signaling pathways. Here, we review the recent advances in the understanding of regulated RNA recognition and signal activation by RLRs, focusing on the interactions between various host and viral factors.
Collapse
Affiliation(s)
- Koji Onomoto
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba, 260-8673, Japan
| | - Kazuhide Onoguchi
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba, 260-8673, Japan
| | - Mitsutoshi Yoneyama
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba, 260-8673, Japan.
| |
Collapse
|
18
|
Donelick HM, Talide L, Bellet M, Aruscavage PJ, Lauret E, Aguiar ERGR, Marques JT, Meignin C, Bass BL. In vitro studies provide insight into effects of Dicer-2 helicase mutations in Drosophila melanogaster. RNA (NEW YORK, N.Y.) 2020; 26:1847-1861. [PMID: 32843367 PMCID: PMC7668257 DOI: 10.1261/rna.077289.120] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 08/20/2020] [Indexed: 05/03/2023]
Abstract
In vitro, Drosophila melanogaster Dicer-2 (Dcr-2) uses its helicase domain to initiate processing of dsRNA with blunt (BLT) termini, and its Platform•PAZ domain to initiate processing of dsRNA with 3' overhangs (ovrs). To understand the relationship of these in vitro observations to roles of Dcr-2 in vivo, we compared in vitro effects of two helicase mutations to their impact on production of endogenous and viral siRNAs in flies. Consistent with the importance of the helicase domain in processing BLT dsRNA, both point mutations eliminated processing of BLT, but not 3'ovr, dsRNA in vitro. However, the mutations had different effects in vivo. A point mutation in the Walker A motif of the Hel1 subdomain, G31R, largely eliminated production of siRNAs in vivo, while F225G, located in the Hel2 subdomain, showed reduced levels of endogenous siRNAs, but did not significantly affect virus-derived siRNAs. In vitro assays monitoring dsRNA cleavage, dsRNA binding, ATP hydrolysis, and binding of the accessory factor Loquacious-PD provided insight into the different effects of the mutations on processing of different sources of dsRNA in flies. Our in vitro studies suggest effects of the mutations in vivo relate to their effects on ATPase activity, dsRNA binding, and interactions with Loquacious-PD. Our studies emphasize the importance of future studies to characterize dsRNA termini as they exist in Drosophila and other animals.
Collapse
Affiliation(s)
- Helen M Donelick
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Loïc Talide
- Université de Strasbourg, CNRS UPR9022, Institut de Biologie Moléculaire et Cellulaire, 67084 Strasbourg, France
| | - Matthieu Bellet
- Université de Strasbourg, CNRS UPR9022, Institut de Biologie Moléculaire et Cellulaire, 67084 Strasbourg, France
| | - P Joseph Aruscavage
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Emilie Lauret
- Université de Strasbourg, CNRS UPR9022, Institut de Biologie Moléculaire et Cellulaire, 67084 Strasbourg, France
| | - Eric R G R Aguiar
- Centro de Biotecnologia e Genética, Universidade Estadual de Santa Cruz, Ilhéus 45662-900, Bahia, Brazil
| | - Joao T Marques
- Université de Strasbourg, CNRS UPR9022, Institut de Biologie Moléculaire et Cellulaire, 67084 Strasbourg, France
- Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Belo Horizonte, CEP 31270-901, Brazil
| | - Carine Meignin
- Université de Strasbourg, CNRS UPR9022, Institut de Biologie Moléculaire et Cellulaire, 67084 Strasbourg, France
| | - Brenda L Bass
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, USA
| |
Collapse
|
19
|
Rutsch F, Buers I, Nitschke Y. Hereditary Disorders of Cardiovascular Calcification. Arterioscler Thromb Vasc Biol 2020; 41:35-47. [PMID: 33176451 DOI: 10.1161/atvbaha.120.315577] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Arterial calcification is a common phenomenon in the elderly, in patients with atherosclerosis or renal failure and in diabetes. However, when present in very young individuals, it is likely to be associated with an underlying hereditary disorder of arterial calcification. Here, we present an overview of the few monogenic disorders presenting with early-onset cardiovascular calcification. These disorders can be classified according to the function of the respective disease gene into (1) disorders caused by an altered purine and phosphate/pyrophosphate metabolism, (2) interferonopathies, and (3) Gaucher disease. The finding of arterial calcification in early life should alert the clinician and prompt further genetic work-up to define the underlying genetic defect, to establish the correct diagnosis, and to enable appropriate therapy.
Collapse
Affiliation(s)
- Frank Rutsch
- Department of General Pediatrics, Muenster University Children's Hospital, Germany
| | - Insa Buers
- Department of General Pediatrics, Muenster University Children's Hospital, Germany
| | - Yvonne Nitschke
- Department of General Pediatrics, Muenster University Children's Hospital, Germany
| |
Collapse
|
20
|
Abu Tayeh A, Funabiki M, Shimizu S, Satoh S, Sumin L, Iwakura Y, Kato H, Fujita T. Psoriasis-like skin disorder in transgenic mice expressing a RIG-I Singleton-Merten syndrome variant. Int Immunol 2020; 33:211-224. [PMID: 33119735 DOI: 10.1093/intimm/dxaa071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/28/2020] [Indexed: 12/15/2022] Open
Abstract
Mutations in DDX58 (DExD/H-box helicase 58), which encodes the cytoplasmic RNA sensor retinoic acid-inducible gene I (RIG-I), were recently identified in the rare autoimmune disease Singleton-Merten syndrome (SMS). We report the spontaneous development of psoriasis-like skin lesions as an SMS-like symptom in transgenic mice harboring one of the RIG-I SMS variants, E373A. Histological analysis revealed typical characteristics of psoriasis, including the abnormal proliferation and differentiation of keratinocytes leading to epidermal hyperplasia, and infiltrates consisting of neutrophils, dendritic cells and T cells. Levels of the IL-23/IL-17 immune axis cytokines were high in the skin lesions. Rag2-/- transgenic mice showed partial amelioration of the phenotype, with down-regulation of inflammatory cytokines, including IL-17A, suggesting the importance of lymphocytes for the pathogenesis similar to that of human psoriasis. Of note, IL-17A deficiency abolished the skin phenotype, and treatment using the JAK inhibitor tofacitinib not only prevented onset, but also improved the skin manifestations even after onset. Our study provides further evidence for the involvement of RIG-I activation in the onset and progression of psoriasis via type I interferon signaling and the IL-23/IL-17 axis.
Collapse
Affiliation(s)
- Ahmed Abu Tayeh
- Laboratory of Regulatory Information, Institute for Frontier Life and Medical Science, Kyoto University, Sakyo-ku, Kyoto, Japan.,Laboratory of Molecular and Cellular Immunology, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Masahide Funabiki
- Laboratory of Regulatory Information, Institute for Frontier Life and Medical Science, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Shota Shimizu
- Laboratory of Regulatory Information, Institute for Frontier Life and Medical Science, Kyoto University, Sakyo-ku, Kyoto, Japan.,Laboratory of Molecular and Cellular Immunology, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Saya Satoh
- Institute of Cardiovascular Immunology, University Hospital Bonn, University of Bonn, Bonn, Germany
| | - Lee Sumin
- Laboratory of Regulatory Information, Institute for Frontier Life and Medical Science, Kyoto University, Sakyo-ku, Kyoto, Japan.,Laboratory of Molecular and Cellular Immunology, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Yoichiro Iwakura
- Center for Animal Disease Models, Research Institute for Science and Technology, Tokyo University of Science, Yamazaki, Chiba, Japan
| | - Hiroki Kato
- Laboratory of Regulatory Information, Institute for Frontier Life and Medical Science, Kyoto University, Sakyo-ku, Kyoto, Japan.,Institute of Cardiovascular Immunology, University Hospital Bonn, University of Bonn, Bonn, Germany
| | - Takashi Fujita
- Laboratory of Regulatory Information, Institute for Frontier Life and Medical Science, Kyoto University, Sakyo-ku, Kyoto, Japan.,Laboratory of Molecular and Cellular Immunology, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto, Japan
| |
Collapse
|
21
|
Jung S, von Thülen T, Yang I, Laukemper V, Rupf B, Janga H, Panagiotidis GD, Schoen A, Nicolai M, Schulte LN, Obermann HL, Weber F, Kaufmann A, Bauer S. A ribosomal RNA fragment with 2',3'-cyclic phosphate and GTP-binding activity acts as RIG-I ligand. Nucleic Acids Res 2020; 48:10397-10412. [PMID: 32946572 PMCID: PMC7544222 DOI: 10.1093/nar/gkaa739] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 08/19/2020] [Accepted: 08/26/2020] [Indexed: 12/13/2022] Open
Abstract
The RNA helicase RIG-I plays a key role in sensing pathogen-derived RNA. Double-stranded RNA structures bearing 5'-tri- or diphosphates are commonly referred to as activating RIG-I ligands. However, endogenous RNA fragments generated during viral infection via RNase L also activate RIG-I. Of note, RNase-digested RNA fragments bear a 5'-hydroxyl group and a 2',3'-cyclic phosphate. How endogenous RNA fragments activate RIG-I despite the lack of 5'-phosphorylation has not been elucidated. Here we describe an endogenous RIG-I ligand (eRL) that is derived from the internal transcribed spacer 2 region (ITS2) of the 45S ribosomal RNA after partial RNase A digestion in vitro, RNase A protein transfection or RNase L activation. The immunostimulatory property of the eRL is dependent on 2',3'-cyclic phosphate and its sequence is characterized by a G-quadruplex containing sequence motif mediating guanosine-5'-triphosphate (GTP) binding. In summary, RNase generated self-RNA fragments with 2',3'-cyclic phosphate function as nucleotide-5'-triphosphate binding aptamers activating RIG-I.
Collapse
Affiliation(s)
- Stephanie Jung
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Tina von Thülen
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Ines Yang
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Medizinische Hochschule Hannover, Carl Neuberg Straße 1, 30625 Hannover, Germany
| | - Viktoria Laukemper
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Benjamin Rupf
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Harshavardhan Janga
- Institut für Lungenforschung/iLung, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Georgios-Dimitrios Panagiotidis
- Institut für Virologie, Fachbereich Veterinärmedizin (FB10), Justus-Liebig-Universität Gießen, Schubertstr. 81, 35392 Gießen, Germany
| | - Andreas Schoen
- Institut für Virologie, Fachbereich Veterinärmedizin (FB10), Justus-Liebig-Universität Gießen, Schubertstr. 81, 35392 Gießen, Germany
| | - Marina Nicolai
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Leon N Schulte
- Institut für Lungenforschung/iLung, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
- Deutsches Zentrum für Lungenforschung (DZL), 35392 Gießen, Germany
| | - Hannah-Lena Obermann
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Friedemann Weber
- Institut für Virologie, Fachbereich Veterinärmedizin (FB10), Justus-Liebig-Universität Gießen, Schubertstr. 81, 35392 Gießen, Germany
| | - Andreas Kaufmann
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Stefan Bauer
- Institut für Immunologie, Philipps-Universität Marburg, BMFZ, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| |
Collapse
|
22
|
Abstract
Retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) are key sensors of virus infection, mediating the transcriptional induction of type I interferons and other genes that collectively establish an antiviral host response. Recent studies have revealed that both viral and host-derived RNAs can trigger RLR activation; this can lead to an effective antiviral response but also immunopathology if RLR activities are uncontrolled. In this Review, we discuss recent advances in our understanding of the types of RNA sensed by RLRs in the contexts of viral infection, malignancies and autoimmune diseases. We further describe how the activity of RLRs is controlled by host regulatory mechanisms, including RLR-interacting proteins, post-translational modifications and non-coding RNAs. Finally, we discuss key outstanding questions in the RLR field, including how our knowledge of RLR biology could be translated into new therapeutics.
Collapse
Affiliation(s)
- 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.
| | - Michaela U Gack
- Department of Microbiology, The University of Chicago, Chicago, IL, USA.
| |
Collapse
|
23
|
Liu G, Gack MU. Distinct and Orchestrated Functions of RNA Sensors in Innate Immunity. Immunity 2020; 53:26-42. [PMID: 32668226 PMCID: PMC7367493 DOI: 10.1016/j.immuni.2020.03.017] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 03/07/2020] [Accepted: 03/07/2020] [Indexed: 12/21/2022]
Abstract
Faithful maintenance of immune homeostasis relies on the capacity of the cellular immune surveillance machinery to recognize "nonself", such as the presence of pathogenic RNA. Several families of pattern-recognition receptors exist that detect immunostimulatory RNA and then induce cytokine-mediated antiviral and proinflammatory responses. Here, we review the distinct features of bona fide RNA sensors, Toll-like receptors and retinoic-acid inducible gene-I (RIG-I)-like receptors in particular, with a focus on their functional specificity imposed by cell-type-dependent expression, subcellular localization, and ligand preference. Furthermore, we highlight recent advances on the roles of nucleotide-binding oligomerization domain (NOD)-like receptors and DEAD-box or DEAH-box RNA helicases in an orchestrated RNA-sensing network and also discuss the relevance of RNA sensor polymorphisms in human disease.
Collapse
Affiliation(s)
- GuanQun Liu
- Department of Microbiology, The University of Chicago, Chicago, IL 60637, USA
| | - Michaela U Gack
- Department of Microbiology, The University of Chicago, Chicago, IL 60637, USA.
| |
Collapse
|
24
|
Lin H, Cao X. Nuclear innate sensors for nucleic acids in immunity and inflammation. Immunol Rev 2020; 297:162-173. [PMID: 32564422 DOI: 10.1111/imr.12893] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 12/19/2022]
Abstract
Innate sensors recognize pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs) to initiate innate immune response by activating downstream signaling. These evolutionarily conserved innate sensors usually locate in the plasma membrane or cytoplasm. However, the nucleus-localized innate sensors are recently found to detect pathogenic nucleic acids for initiating innate response, demonstrating a complicated crosstalk with cytoplasmic sensors and signaling molecules to form an elaborate tiered innate signaling network between nucleus and cytoplasm. Furthermore, these nuclear innate sensors evolve varied mechanisms for discriminating self from non-self nucleic acids to maintain immune homeostasis and avoid autoinflammatory immune response. In this review, we summarize the recent findings on the identification of nuclear innate sensors for nucleic acids, such as hnRNPA2B1, IFI16, SAFA, and their roles in host defense and inflammatory response.
Collapse
Affiliation(s)
- Hongyu Lin
- Center for Immunotherapy, Institute of Basic Medical Sciences, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Xuetao Cao
- Center for Immunotherapy, Institute of Basic Medical Sciences, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.,Laboratory of Immunity and Inflammation, College of Life Science, Nankai University, Tianjin, China
| |
Collapse
|
25
|
Schweinoch D, Bachmann P, Clausznitzer D, Binder M, Kaderali L. Mechanistic modeling explains the dsRNA length-dependent activation of the RIG-I mediated immune response. J Theor Biol 2020; 500:110336. [PMID: 32446742 DOI: 10.1016/j.jtbi.2020.110336] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 05/13/2020] [Accepted: 05/15/2020] [Indexed: 12/25/2022]
Abstract
In cell-intrinsic antiviral immunity, cytoplasmic receptors such as retinoic acid-inducible gene I (RIG-I) detect viral double-stranded RNA (dsRNA) and trigger a signaling cascade activating the interferon (IFN) system. This leads to the transcription of hundreds of interferon-stimulated genes (ISGs) with a wide range of antiviral effects. This recognition of dsRNA not only has to be very specific to discriminate foreign from self but also highly sensitive to detect even very low numbers of pathogenic dsRNA molecules. Previous work indicated an influence of the dsRNA length on the binding behavior of RIG-I and its potential to elicit antiviral signaling. However, the molecular mechanisms behind the binding process are still under debate. We compare two hypothesized RIG-I binding mechanisms by translating them into mathematical models and analyzing their potential to describe published experimental data. The models consider the length of the dsRNA as well as known RIG-I binding motifs and describe RIG-I pathway activation after stimulation with dsRNA. We show that internal RIG-I binding sites in addition to cooperative RIG-I oligomerization are essential to describe the experimentally observed RIG-I binding behavior and immune response activation for different dsRNA lengths and concentrations. The combination of RIG-I binding to internal sites on the dsRNA and cooperative oligomerization compensates for a lack of high-affinity binding motifs and triggers a strong antiviral response for long dsRNAs. Model analysis reveals dsRNA length-dependency as a potential mechanism to discriminate between different types of dsRNAs: It allows for sensitive detection of small numbers of long dsRNAs, a typical by-product of viral replication, while ensuring tolerance against non-harming small dsRNAs.
Collapse
Affiliation(s)
- Darius Schweinoch
- University Medicine Greifswald, Institute of Bioinformatics and Center for Functional Genomics of Microbes (C_FunGene), Felix-Hausdorff-Str. 8, 17475 Greifswald, Germany
| | - Pia Bachmann
- University Medicine Greifswald, Institute of Bioinformatics and Center for Functional Genomics of Microbes (C_FunGene), Felix-Hausdorff-Str. 8, 17475 Greifswald, Germany
| | - Diana Clausznitzer
- Technische Universität Dresden, Faculty of Medicine Carl-Gustav Carus, Institute for Medical Informatics and Biometry, Dresden, 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
| | - Lars Kaderali
- University Medicine Greifswald, Institute of Bioinformatics and Center for Functional Genomics of Microbes (C_FunGene), Felix-Hausdorff-Str. 8, 17475 Greifswald, Germany.
| |
Collapse
|
26
|
Dumesic PA, Stoddard CI, Catania S, Narlikar GJ, Madhani HD. ATP Hydrolysis by the SNF2 Domain of Dnmt5 Is Coupled to Both Specific Recognition and Modification of Hemimethylated DNA. Mol Cell 2020; 79:127-139.e4. [PMID: 32437639 DOI: 10.1016/j.molcel.2020.04.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 01/01/2023]
Abstract
C.neoformans Dnmt5 is an unusually specific maintenance-type CpG methyltransferase (DNMT) that mediates long-term epigenome evolution. It harbors a DNMT domain and SNF2 ATPase domain. We find that the SNF2 domain couples substrate specificity to an ATPase step essential for DNA methylation. Coupling occurs independent of nucleosomes. Hemimethylated DNA preferentially stimulates ATPase activity, and mutating Dnmt5's ATP-binding pocket disproportionately reduces ATPase stimulation by hemimethylated versus unmethylated substrates. Engineered DNA substrates that stabilize a reaction intermediate by mimicking a "flipped-out" conformation of the target cytosine bypass the SNF2 domain's requirement for hemimethylation. This result implies that ATP hydrolysis by the SNF2 domain is coupled to the DNMT domain conformational changes induced by preferred substrates. These findings establish a new role for a SNF2 ATPase: controlling an adjoined enzymatic domain's substrate recognition and catalysis. We speculate that this coupling contributes to the exquisite specificity of Dnmt5 via mechanisms related to kinetic proofreading.
Collapse
Affiliation(s)
- Phillip A Dumesic
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Caitlin I Stoddard
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Sandra Catania
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Geeta J Narlikar
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
| | - Hiten D Madhani
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA; Chan-Zuckerberg Biohub, San Francisco, CA 94158, USA.
| |
Collapse
|
27
|
Caenorhabditis elegans ADAR editing and the ERI-6/7/MOV10 RNAi pathway silence endogenous viral elements and LTR retrotransposons. Proc Natl Acad Sci U S A 2020; 117:5987-5996. [PMID: 32123111 PMCID: PMC7084138 DOI: 10.1073/pnas.1919028117] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Silencing of transposable elements and viruses is critical for the maintenance of genome integrity, cellular homeostasis, and organismal health. Here we describe multiple factors that control different types of transposable elements, providing insight into how they are regulated. We also identify stress response pathways that are triggered upon misregulation of these transposable elements. The conservation of these factors and pathways in human suggests that our studies in Caenorhabditis elegans can provide general insight into the regulation of and response to transposable elements and viruses. Endogenous retroviruses and long terminal repeat (LTR) retrotransposons are mobile genetic elements that are closely related to retroviruses. Desilenced endogenous retroviruses are associated with human autoimmune disorders and neurodegenerative diseases. Caenorhabditis elegans and related Caenorhabditis spp. contain LTR retrotransposons and, as described here, numerous integrated viral genes including viral envelope genes that are part of LTR retrotransposons. We found that both LTR retrotransposons and endogenous viral elements are silenced by ADARs [adenosine deaminases acting on double-stranded RNA (dsRNA)] together with the endogenous RNA interference (RNAi) factor ERI-6/7, a homolog of MOV10 helicase, a retrotransposon and retrovirus restriction factor in human. siRNAs corresponding to integrated viral genes and LTR retrotransposons, but not to DNA transposons, are dependent on the ADARs and ERI-6/7. siRNAs corresponding to palindromic repeats are independent of the ADARs and ERI-6/7, and are in fact increased in adar- and eri-6/7–defective mutants because of an antiviral RNAi response to dsRNA. Silencing of LTR retrotransposons is dependent on downstream RNAi factors and P granule components but is independent of the viral sensor DRH-1/RIG-I and the nuclear Argonaute NRDE-3. The activation of retrotransposons in the ADAR- and ERI-6/7/MOV10–defective mutant is associated with the induction of the unfolded protein response (UPR), a common response to viral infection. The overlap between genes induced upon viral infection and infection with intracellular pathogens and genes coexpressed with retrotransposons suggests that there is a common response to different types of foreign elements that includes a response to proteotoxicity presumably caused by the burden of replicating pathogens and expressed retrotransposons.
Collapse
|
28
|
Ren X, Linehan MM, Iwasaki A, Pyle AM. RIG-I Recognition of RNA Targets: The Influence of Terminal Base Pair Sequence and Overhangs on Affinity and Signaling. Cell Rep 2019; 29:3807-3815.e3. [PMID: 31851914 DOI: 10.1016/j.celrep.2019.11.052] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 09/24/2019] [Accepted: 11/13/2019] [Indexed: 12/25/2022] Open
Abstract
Within the complex environment of the human cell, the RIG-I innate immune receptor must detect the presence of double-stranded viral RNA molecules and differentiate them from a diversity of host RNA molecules. In an ongoing effort to understand the molecular basis for RIG-I target specificity, here, we evaluate the ability of this sensor to respond to triphosphorylated, double-stranded RNA molecules that contain all possible terminal base pairs and common mismatches. In addition, we test the response to duplexes with various types of 5' and 3' overhangs. We conducted quantitative measurements of RNA ligand affinity, then tested RNA variants for their ability to stimulate the RIG-I-dependent interferon response in cells and in whole animals. The resulting data provide insights into the design of RNA therapeutics that prevent RIG-I activation, and they provide valuable insights into the mechanisms of evasion by deadly pathogens such as the Ebola and Marburg viruses.
Collapse
Affiliation(s)
- Xiaoming Ren
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University, New Haven, CT 06520, USA
| | - Melissa M Linehan
- Department of Immunobiology, Yale University, New Haven, CT 06520, USA
| | - Akiko Iwasaki
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA; Department of Immunobiology, Yale University, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University, New Haven, CT 06520, USA
| | - Anna Marie Pyle
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University, New Haven, CT 06520, USA.
| |
Collapse
|
29
|
Dickey TH, Song B, Pyle AM. RNA binding activates RIG-I by releasing an autorepressed signaling domain. SCIENCE ADVANCES 2019; 5:eaax3641. [PMID: 31616790 PMCID: PMC6774723 DOI: 10.1126/sciadv.aax3641] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
The retinoic acid-inducible gene I (RIG-I) innate immune receptor is an important immunotherapeutic target, but we lack approaches for monitoring the physical basis for its activation in vitro. This gap in our understanding has led to confusion about mechanisms of RIG-I activation and difficulty discovering agonists and antagonists. We therefore created a novel fluorescence resonance energy transfer-based method for measuring RIG-I activation in vitro using dual site-specific fluorescent labeling of the protein. This approach enables us to measure the conformational change that releases the signaling domain during the first step of RIG-I activation, making it possible to understand the role of stimulatory ligands. We have found that RNA alone is sufficient to eject the signaling domain, ejection is reversible, and adenosine triphosphate plays but a minor role in this process. These findings help explain RIG-I dysfunction in autoimmune disease, and they inform the design of therapeutics targeting RIG-I.
Collapse
Affiliation(s)
- T. H. Dickey
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - B. Song
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - A. M. Pyle
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Howard Hughes Medical Institute, Yale University, New Haven, CT, USA
| |
Collapse
|
30
|
Brisse M, Ly H. Comparative Structure and Function Analysis of the RIG-I-Like Receptors: RIG-I and MDA5. Front Immunol 2019; 10:1586. [PMID: 31379819 PMCID: PMC6652118 DOI: 10.3389/fimmu.2019.01586] [Citation(s) in RCA: 218] [Impact Index Per Article: 43.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 06/25/2019] [Indexed: 12/12/2022] Open
Abstract
RIG-I (Retinoic acid-inducible gene I) and MDA5 (Melanoma Differentiation-Associated protein 5), collectively known as the RIG-I-like receptors (RLRs), are key protein sensors of the pathogen-associated molecular patterns (PAMPs) in the form of viral double-stranded RNA (dsRNA) motifs to induce expression of type 1 interferons (IFN1) (IFNα and IFNβ) and other pro-inflammatory cytokines during the early stage of viral infection. While RIG-I and MDA5 share many genetic, structural and functional similarities, there is increasing evidence that they can have significantly different strategies to recognize different pathogens, PAMPs, and in different host species. This review article discusses the similarities and differences between RIG-I and MDA5 from multiple perspectives, including their structures, evolution and functional relationships with other cellular proteins, their differential mechanisms of distinguishing between host and viral dsRNAs and interactions with host and viral protein factors, and their immunogenic signaling. A comprehensive comparative analysis can help inform future studies of RIG-I and MDA5 in order to fully understand their functions in order to optimize potential therapeutic approaches targeting them.
Collapse
Affiliation(s)
- Morgan Brisse
- Biochemistry, Molecular Biology, and Biophysics Graduate Program, University of Minnesota, Twin Cities, St. Paul, MN, United States
- Department of Veterinary & Biomedical Sciences, University of Minnesota, Twin Cities, St. Paul, MN, United States
| | - Hinh Ly
- Department of Veterinary & Biomedical Sciences, University of Minnesota, Twin Cities, St. Paul, MN, United States
| |
Collapse
|
31
|
Ho V, Yong HY, Chevrier M, Narang V, Lum J, Toh YX, Lee B, Chen J, Tan EY, Luo D, Fink K. RIG-I Activation by a Designer Short RNA Ligand Protects Human Immune Cells against Dengue Virus Infection without Causing Cytotoxicity. J Virol 2019; 93:e00102-19. [PMID: 31043531 PMCID: PMC6600207 DOI: 10.1128/jvi.00102-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 04/23/2019] [Indexed: 12/25/2022] Open
Abstract
Virus-derived double-stranded RNA (dsRNA) molecules containing a triphosphate group at the 5' end are natural ligands of retinoic acid-inducible gene I (RIG-I). The cellular pathways and proteins induced by RIG-I are an essential part of the innate immune response against viral infections. Starting from a previously published RNA scaffold (3p10L), we characterized an optimized small dsRNA hairpin (called 3p10LG9, 25 nucleotides [nt] in length) as a highly efficient RIG-I activator. Dengue virus (DENV) infection in cell lines and primary human skin cells could be prevented and restricted through 3p10LG9-mediated activation of RIG-I. This antiviral effect was RIG-I and interferon signal dependent. The effect was temporary and was reversed above a saturating concentration of RIG-I ligand. This finding revealed an effective feedback loop that controls potentially damaging inflammatory effects of the RIG-I response, at least in immune cells. Our results show that the small RIG-I activator 3p10LG9 can confer short-term protection against DENV and can be further explored as an antiviral treatment in humans.IMPORTANCE Short hairpin RNA ligands that activate RIG-I induce antiviral responses in infected cells and prevent or control viral infections. Here, we characterized a new short hairpin RNA molecule with high efficacy in antiviral gene activation and showed that this molecule is able to control dengue virus infection. We demonstrate how structural modifications of minimal RNA ligands can lead to increased potency and a wider window of RIG-I-activating concentrations before regulatory mechanisms kick in at high concentrations. We also show that minimal RNA ligands induce an effective antiviral response in human skin dendritic cells and macrophages, which are the target cells of initial infection after the mosquito releases virus into the skin. Using short hairpin RNA as RIG-I ligands could therefore be explored as antiviral therapy.
Collapse
Affiliation(s)
- Victor Ho
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Hui Yee Yong
- School of Biological Sciences, Nanyang Technological University, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Marion Chevrier
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
| | - Vipin Narang
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
| | - Josephine Lum
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
| | - Ying-Xiu Toh
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
| | - Bernett Lee
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
| | - Jinmiao Chen
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
| | - Ern Yu Tan
- Department of General Surgery, Tan Tock Seng Hospital, Singapore
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Katja Fink
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| |
Collapse
|
32
|
Pattabhi S, Knoll ML, Gale M, Loo YM. DHX15 Is a Coreceptor for RLR Signaling That Promotes Antiviral Defense Against RNA Virus Infection. J Interferon Cytokine Res 2019; 39:331-346. [PMID: 31090472 PMCID: PMC6590726 DOI: 10.1089/jir.2018.0163] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/01/2019] [Indexed: 12/23/2022] Open
Abstract
RNA helicases play an important role in the response to microbial infection. Retinoic acid inducible gene-I (RIG-I) and members of the RIG-I-like receptor (RLR) family of helicases function as cytoplasmic pattern recognition receptors (PRRs) whose actions are essential for recognition of RNA viruses. RIG-I association with pathogen-associated molecular patterns (PAMPs) within viral RNA leads to its activation and signaling via the mitochondrial antiviral signaling (MAVS) adapter protein. This interaction mediates downstream signaling events that drive the innate immune response to virus infection. Here we identify the DEAH-box RNA helicase DHX15 as a RLR binding partner and signaling cofactor. In human cells, DHX15 is required for virus-induced RLR signaling of innate immune gene expression. Knockdown of DHX15 increased susceptibility to infection by RNA viruses of diverse genera, including Paramyxoviridae, Rhabdoviridae, and Picornaviridae. DHX15 associates with RIG-I caspase activation and recruitment domains (CARDs) through its amino terminus, in which the complex is recruited to MAVS on virus infection. Importantly, although DHX15 cannot substitute for RIG-I in innate immune signaling, DHX15 selectively binds PAMP RNA to promote RIG-I ATP hydrolysis and signaling activation in response to viral RNA. Our results define DHX15 as a coreceptor required for RLR innate immune responses to control RNA virus infection.
Collapse
Affiliation(s)
- Sowmya Pattabhi
- Department of Global Health, University of Washington, Seattle, Washington
- Department of Immunology, Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
| | - Megan L. Knoll
- Department of Immunology, Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
- Department of Immunology, University of Washington, Seattle, Washington
| | - Michael Gale
- Department of Global Health, University of Washington, Seattle, Washington
- Department of Immunology, Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
- Department of Immunology, University of Washington, Seattle, Washington
| | - Yueh-Ming Loo
- Department of Immunology, Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
- Department of Immunology, University of Washington, Seattle, Washington
| |
Collapse
|
33
|
The long noncoding RNA Lnczc3h7a promotes a TRIM25-mediated RIG-I antiviral innate immune response. Nat Immunol 2019; 20:812-823. [PMID: 31036902 DOI: 10.1038/s41590-019-0379-0] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 03/18/2019] [Indexed: 12/22/2022]
Abstract
The helicase RIG-I initiates an antiviral immune response after recognition of pathogenic RNA. TRIM25, an E3 ubiquitin ligase, mediates K63-linked ubiquitination of RIG-I, which is crucial for RIG-I downstream signaling and the antiviral innate immune response. The components and mode of the RIG-I-initiated innate signaling remain to be fully understood. Here we identify a novel long noncoding RNA (Lnczc3h7a) that binds to TRIM25 and promotes RIG-I-mediated antiviral innate immune responses. Depletion of Lnczc3h7a impairs RIG-I signaling and the antiviral innate response to RNA viruses in vitro and in vivo. Mechanistically, Lnczc3h7a binds to both TRIM25 and activated RIG-I, serving as a molecular scaffold for stabilization of the RIG-I-TRIM25 complex at the early stage of viral infection. Lnczc3h7a facilitates TRIM25-mediated K63-linked ubiquitination of RIG-I and thus promotes downstream signaling transduction. Our findings reveal that host RNAs can enhance the response of innate immune sensors to foreign RNAs, ensuring effective antiviral defense.
Collapse
|
34
|
Ng CS, Kato H, Fujita T. Fueling Type I Interferonopathies: Regulation and Function of Type I Interferon Antiviral Responses. J Interferon Cytokine Res 2019; 39:383-392. [PMID: 30897023 DOI: 10.1089/jir.2019.0037] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In conjunction with the development of genome-wide technology, numerous studies have revealed the importance of regulatory mechanisms to avoid the onset of autoimmunity. In this, protein regulators and the newly identified low-abundant RNA species participate in the regulation of type I interferon (IFN-I) and proinflammatory genes induced by innate immune sensors. In this review, we briefly look into some of the autoimmune diseases profiled by dysregulations of IFN-I signaling and the regulatory mechanisms critical for immunological homeostasis.
Collapse
Affiliation(s)
- Chen Seng Ng
- 1 Institute for Quantitative and Computational Biosciences, Immunology and Molecular Genetics, University of California, Los Angeles, California.,2 Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, California
| | - Hiroki Kato
- 3 Institute of Cardiovascular Immunology, University Hospitals, University of Bonn, Bonn, Germany
| | - Takashi Fujita
- 4 Laboratory of Molecular Genetics, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,5 Laboratory of Molecular and Cellular Immunology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| |
Collapse
|
35
|
Abstract
Long double-stranded RNAs (dsRNAs) are abundantly expressed in animals, in which they frequently occur in introns and 3' untranslated regions of mRNAs. Functions of long, cellular dsRNAs are poorly understood, although deficiencies in adenosine deaminases that act on RNA, or ADARs, promote their recognition as viral dsRNA and an aberrant immune response. Diverse dsRNA-binding proteins bind cellular dsRNAs, hinting at additional roles. Understanding these roles is facilitated by mapping the genomic locations that express dsRNA in various tissues and organisms. ADAR editing provides a signature of dsRNA structure in cellular transcripts. In this review, we detail approaches to map ADAR editing sites and dsRNAs genome-wide, with particular focus on high-throughput sequencing methods and considerations for their successful application to the detection of editing sites and dsRNAs.
Collapse
Affiliation(s)
- Daniel P Reich
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112
| | - Brenda L Bass
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112
| |
Collapse
|
36
|
Kasumba DM, Grandvaux N. Therapeutic Targeting of RIG-I and MDA5 Might Not Lead to the Same Rome. Trends Pharmacol Sci 2019; 40:116-127. [PMID: 30606502 PMCID: PMC7112877 DOI: 10.1016/j.tips.2018.12.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/05/2018] [Accepted: 12/06/2018] [Indexed: 12/12/2022]
Abstract
RIG-I and MDA5 receptors are key sensors of pathogen-associated molecular pattern (PAMP)-containing viral RNA and transduce downstream signals to activate an antiviral and immunomodulatory response. Fifteen years of research have put them at the center of an ongoing hunt for novel pharmacological pan-antivirals, vaccine adjuvants, and antitumor strategies. Current knowledge testifies to the redundant, but also distinct, functions mediated by RIG-I and MDA5, opening opportunities for the use of specific and potent nucleic acid agonists. We critically discuss the evidence and remaining knowledge gaps that have an impact on the choice and design of optimal RNA ligands to achieve an appropriate immunostimulatory response, with limited adverse effects, for prophylactic and therapeutic interventions against viruses and cancer in humans.
Collapse
Affiliation(s)
- Dacquin M. Kasumba
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, QC, Canada,Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Nathalie Grandvaux
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, QC, Canada; Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada.
| |
Collapse
|
37
|
Zheng J, Wang C, Chang MR, Devarkar SC, Schweibenz B, Crynen GC, Garcia-Ordonez RD, Pascal BD, Novick SJ, Patel SS, Marcotrigiano J, Griffin PR. HDX-MS reveals dysregulated checkpoints that compromise discrimination against self RNA during RIG-I mediated autoimmunity. Nat Commun 2018; 9:5366. [PMID: 30560918 PMCID: PMC6299088 DOI: 10.1038/s41467-018-07780-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 11/28/2018] [Indexed: 01/25/2023] Open
Abstract
Retinoic acid inducible gene-I (RIG-I) ensures immune surveillance of viral RNAs bearing a 5'-triphosphate (5'ppp) moiety. Mutations in RIG-I (C268F and E373A) lead to impaired ATPase activity, thereby driving hyperactive signaling associated with autoimmune diseases. Here we report, using hydrogen/deuterium exchange, mechanistic models for dysregulated RIG-I proofreading that ultimately result in the improper recognition of cellular RNAs bearing 7-methylguanosine and N1-2'-O-methylation (Cap1) on the 5' end. Cap1-RNA compromises its ability to stabilize RIG-I helicase and blunts caspase activation and recruitment domains (CARD) partial opening by threefold. RIG-I H830A mutation restores Cap1-helicase engagement as well as CARDs partial opening event to a level comparable to that of 5'ppp. However, E373A RIG-I locks the receptor in an ATP-bound state, resulting in enhanced Cap1-helicase engagement and a sequential CARDs stimulation. C268F mutation renders a more tethered ring architecture and results in constitutive CARDs signaling in an ATP-independent manner.
Collapse
MESH Headings
- Adenosine Triphosphatases/metabolism
- Autoimmunity/genetics
- Caspase Activation and Recruitment Domain/immunology
- DEAD Box Protein 58/chemistry
- DEAD Box Protein 58/genetics
- DEAD Box Protein 58/immunology
- DEAD Box Protein 58/metabolism
- Deuterium Exchange Measurement/methods
- Gain of Function Mutation
- Guanosine/analogs & derivatives
- Guanosine/chemistry
- Guanosine/immunology
- Guanosine/metabolism
- Immunity, Innate/genetics
- Interferon-Induced Helicase, IFIH1/immunology
- Interferon-Induced Helicase, IFIH1/metabolism
- Mass Spectrometry/methods
- Methylation
- Models, Molecular
- Mutagenesis, Site-Directed
- Protein Binding/genetics
- Protein Binding/immunology
- RNA Caps/chemistry
- RNA Caps/immunology
- RNA Caps/metabolism
- RNA, Double-Stranded/chemistry
- RNA, Double-Stranded/immunology
- RNA, Double-Stranded/metabolism
- RNA, Viral/immunology
- Receptors, Immunologic
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/immunology
- Recombinant Proteins/metabolism
- Signal Transduction/genetics
- Signal Transduction/immunology
Collapse
Affiliation(s)
- Jie Zheng
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458, USA.
| | - Chen Wang
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mi Ra Chang
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458, USA
| | - Swapnil C Devarkar
- Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, 08854, USA
| | - Brandon Schweibenz
- Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, 08854, USA
| | - Gogce C Crynen
- The Center for Computational Biology, The Scripps Research Institute, Jupiter, FL, 33458, USA
| | - Ruben D Garcia-Ordonez
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458, USA
| | - Bruce D Pascal
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458, USA
- Omics Informatics LLC, Honolulu, HI 96813, USA
| | - Scott J Novick
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458, USA
| | - Smita S Patel
- Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, 08854, USA
| | - Joseph Marcotrigiano
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Patrick R Griffin
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, 33458, USA.
| |
Collapse
|
38
|
Khan S, Godfrey V, Zaki MH. Cytosolic Nucleic Acid Sensors in Inflammatory and Autoimmune Disorders. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 344:215-253. [PMID: 30798989 DOI: 10.1016/bs.ircmb.2018.10.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Innate immunity employs germline-encoded pattern recognition receptors (PRRs) to sense microbial pattern molecules. Recognition of pathogen-associated molecular patterns (PAMPs) by various PPRs located on the cell membrane or in the cytosol leads to the activation of cell signaling pathways and production of inflammatory mediators. Nucleic acids including DNA, RNA, and their derivatives are potent PAMPs which can be recognized by multiple PRRs to induce inflammatory responses. While nucleic acid sensors can also sense endogenous nucleic acids, they are capable of discriminating self from non-self. However, defects in nucleic acid sensing PRRs or dysregulation of nucleic acid sensing signaling pathways may cause excessive activation of the immune system resulting in the development of inflammatory and autoimmune diseases. This review will discuss the major pathways for sensing intracellular nucleic acids and how defects in these nucleic acid sensing are associated with different kinds of autoimmune and inflammatory disorders.
Collapse
Affiliation(s)
- Shahanshah Khan
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Victoria Godfrey
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Md Hasan Zaki
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, United States.
| |
Collapse
|
39
|
Yu Q, Qu K, Modis Y. Cryo-EM Structures of MDA5-dsRNA Filaments at Different Stages of ATP Hydrolysis. Mol Cell 2018; 72:999-1012.e6. [PMID: 30449722 PMCID: PMC6310684 DOI: 10.1016/j.molcel.2018.10.012] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 08/09/2018] [Accepted: 10/09/2018] [Indexed: 12/24/2022]
Abstract
Double-stranded RNA (dsRNA) is a potent proinflammatory signature of viral infection. Long cytosolic dsRNA is recognized by MDA5. The cooperative assembly of MDA5 into helical filaments on dsRNA nucleates the assembly of a multiprotein type I interferon signaling platform. Here, we determined cryoelectron microscopy (cryo-EM) structures of MDA5-dsRNA filaments with different helical twists and bound nucleotide analogs at resolutions sufficient to build and refine atomic models. The structures identify the filament-forming interfaces, which encode the dsRNA binding cooperativity and length specificity of MDA5. The predominantly hydrophobic interface contacts confer flexibility, reflected in the variable helical twist within filaments. Mutation of filament-forming residues can result in loss or gain of signaling activity. Each MDA5 molecule spans 14 or 15 RNA base pairs, depending on the twist. Variations in twist also correlate with variations in the occupancy and type of nucleotide in the active site, providing insights on how ATP hydrolysis contributes to MDA5-dsRNA recognition. Cryo-EM structures of MDA5-dsRNA filaments determined for three catalytic states Filament forming interfaces are flexible and predominantly hydrophobic Mutation of filament-forming residues can cause loss or gain of IFN-β signaling ATPase cycle is coupled to changes in filament twist and size of the RNA footprint
Collapse
Affiliation(s)
- Qin Yu
- Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | - Kun Qu
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | - Yorgo Modis
- Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
| |
Collapse
|
40
|
Devarkar SC, Schweibenz B, Wang C, Marcotrigiano J, Patel SS. RIG-I Uses an ATPase-Powered Translocation-Throttling Mechanism for Kinetic Proofreading of RNAs and Oligomerization. Mol Cell 2018; 72:355-368.e4. [PMID: 30270105 PMCID: PMC6434538 DOI: 10.1016/j.molcel.2018.08.021] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 06/15/2018] [Accepted: 08/14/2018] [Indexed: 12/25/2022]
Abstract
RIG-I has a remarkable ability to specifically select viral 5'ppp dsRNAs for activation from a pool of cytosolic self-RNAs. The ATPase activity of RIG-I plays a role in RNA discrimination and activation, but the underlying mechanism was unclear. Using transient-state kinetics, we elucidated the ATPase-driven "kinetic proofreading" mechanism of RIG-I activation and RNA discrimination, akin to DNA polymerases, ribosomes, and T cell receptors. Even in the autoinhibited state of RIG-I, the C-terminal domain kinetically discriminates against self-RNAs by fast off rates. ATP binding facilitates dsRNA engagement but, interestingly, makes RIG-I promiscuous, explaining the constitutive signaling by Singleton-Merten syndrome-linked mutants that bind ATP without hydrolysis. ATP hydrolysis dissociates self-RNAs faster than 5'ppp dsRNA but, more importantly, drives RIG-I oligomerization through translocation, which we show to be regulated by helicase motif IVa. RIG-I translocates directionally from the dsRNA end into the stem region, and the 5'ppp end "throttles" translocation to provide a mechanism for threading and building a signaling-active oligomeric complex.
Collapse
Affiliation(s)
- Swapnil C Devarkar
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
| | - Brandon Schweibenz
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
| | - Chen Wang
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Joseph Marcotrigiano
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA.
| | - Smita S Patel
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA.
| |
Collapse
|
41
|
Lässig C, Lammens K, Gorenflos López JL, Michalski S, Fettscher O, Hopfner KP. Unified mechanisms for self-RNA recognition by RIG-I Singleton-Merten syndrome variants. eLife 2018; 7:e38958. [PMID: 30047865 PMCID: PMC6086658 DOI: 10.7554/elife.38958] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 07/24/2018] [Indexed: 12/13/2022] Open
Abstract
The innate immune sensor retinoic acid-inducible gene I (RIG-I) detects cytosolic viral RNA and requires a conformational change caused by both ATP and RNA binding to induce an active signaling state and to trigger an immune response. Previously, we showed that ATP hydrolysis removes RIG-I from lower-affinity self-RNAs (Lässig et al., 2015), revealing how ATP turnover helps RIG-I distinguish viral from self-RNA and explaining why a mutation in a motif that slows down ATP hydrolysis causes the autoimmune disease Singleton-Merten syndrome (SMS). Here we show that a different, mechanistically unexplained SMS variant, C268F, which is localized in the ATP-binding P-loop, can signal independently of ATP but is still dependent on RNA. The structure of RIG-I C268F in complex with double-stranded RNA reveals that C268F helps induce a structural conformation in RIG-I that is similar to that induced by ATP. Our results uncover an unexpected mechanism to explain how a mutation in a P-loop ATPase can induce a gain-of-function ATP state in the absence of ATP.
Collapse
Affiliation(s)
- Charlotte Lässig
- Department of BiochemistryLudwig-Maximilians-Universität MünchenMunichGermany
- Gene Center, Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Katja Lammens
- Department of BiochemistryLudwig-Maximilians-Universität MünchenMunichGermany
- Gene Center, Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Jacob Lucián Gorenflos López
- Department of BiochemistryLudwig-Maximilians-Universität MünchenMunichGermany
- Gene Center, Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Sebastian Michalski
- Department of BiochemistryLudwig-Maximilians-Universität MünchenMunichGermany
- Gene Center, Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Olga Fettscher
- Department of BiochemistryLudwig-Maximilians-Universität MünchenMunichGermany
- Gene Center, Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Karl-Peter Hopfner
- Department of BiochemistryLudwig-Maximilians-Universität MünchenMunichGermany
- Gene Center, Ludwig-Maximilians-Universität MünchenMunichGermany
- Center for Integrated Protein Science MunichMunichGermany
| |
Collapse
|
42
|
Lee W, Lee SH, Kim M, Moon JS, Kim GW, Jung HG, Kim IH, Oh JE, Jung HE, Lee HK, Ku KB, Ahn DG, Kim SJ, Kim KS, Oh JW. Vibrio vulnificus quorum-sensing molecule cyclo(Phe-Pro) inhibits RIG-I-mediated antiviral innate immunity. Nat Commun 2018; 9:1606. [PMID: 29686409 PMCID: PMC5913291 DOI: 10.1038/s41467-018-04075-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 04/03/2018] [Indexed: 02/06/2023] Open
Abstract
The recognition of pathogen-derived ligands by pattern recognition receptors activates the innate immune response, but the potential interaction of quorum-sensing (QS) signaling molecules with host anti-viral defenses remains largely unknown. Here we show that the Vibrio vulnificus QS molecule cyclo(Phe-Pro) (cFP) inhibits interferon (IFN)-β production by interfering with retinoic-acid-inducible gene-I (RIG-I) activation. Binding of cFP to the RIG-I 2CARD domain induces a conformational change in RIG-I, preventing the TRIM25-mediated ubiquitination to abrogate IFN production. cFP enhances susceptibility to hepatitis C virus (HCV), as well as Sendai and influenza viruses, each known to be sensed by RIG-I but did not affect the melanoma-differentiation-associated gene 5 (MDA5)-recognition of norovirus. Our results reveal an inter-kingdom network between bacteria, viruses and host that dysregulates host innate responses via a microbial quorum-sensing molecule modulating the response to viral infection.
Collapse
Affiliation(s)
- Wooseong Lee
- Department of Biotechnology, Yonsei University, Seoul, 03722, Korea
| | - Seung-Hoon Lee
- Department of Biotechnology, Yonsei University, Seoul, 03722, Korea
| | - Minwoo Kim
- Department of Biotechnology, Yonsei University, Seoul, 03722, Korea
| | - Jae-Su Moon
- Department of Biotechnology, Yonsei University, Seoul, 03722, Korea
| | - Geon-Woo Kim
- Department of Biotechnology, Yonsei University, Seoul, 03722, Korea
| | - Hae-Gwang Jung
- Department of Biotechnology, Yonsei University, Seoul, 03722, Korea
| | - In Hwang Kim
- Department of Life Science, Sogang University, Seoul, 04107, Korea
| | - Ji Eun Oh
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea
| | - Hi Eun Jung
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea
| | - Heung Kyu Lee
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea
| | - Keun Bon Ku
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon, 34114, Korea
| | - Dae-Gyun Ahn
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon, 34114, Korea
| | - Seong-Jun Kim
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon, 34114, Korea
| | - Kun-Soo Kim
- Department of Life Science, Sogang University, Seoul, 04107, Korea
| | - Jong-Won Oh
- Department of Biotechnology, Yonsei University, Seoul, 03722, Korea.
| |
Collapse
|
43
|
Buers I, Rice GI, Crow YJ, Rutsch F. MDA5-Associated Neuroinflammation and the Singleton-Merten Syndrome: Two Faces of the Same Type I Interferonopathy Spectrum. J Interferon Cytokine Res 2018; 37:214-219. [PMID: 28475458 DOI: 10.1089/jir.2017.0004] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In 1973, Singleton and Merten described a new syndrome in 2 female probands with aortic and cardiac valve calcifications, early loss of secondary dentition, and widened medullary cavities of the phalanges. In 1984, Aicardi and Goutières defined a phenotype resembling congenital viral infection with basal ganglia calcification and increased protein content in the cerebrospinal fluid. Between 2006 and 2012, mutations in 6 different genes were described to be associated with Aicardi-Goutières syndrome, specifically-TREX1, RNASEH2A, RNASEH2B, RNASEH2C, ADAR, and SAMHD1. More recently, mutations in IFIH1 were reported in a variety of neuroimmunological phenotypes, including Aicardi-Goutières syndrome, while a specific Arg822Gln mutation in IFIH1 was described in 3 discrete families with Singleton-Merten syndrome (SMS). IFIH1 encodes for melanoma differentiation-associated gene 5 (MDA5), and all mutations identified to date have been associated with an enhanced interferon response in affected individuals. In this study, we present a male child demonstrating recurrent febrile episodes, spasticity, and basal ganglia calcification suggestive of Aicardi-Goutières syndrome, who carries the same Arg822Gln mutation in IFIH1 previously associated with SMS. We conclude that both diseases are part of the interferonopathy grouping and that the Arg822Gln mutation in IFIH1 can cause a spectrum of disease, including neurological involvement.
Collapse
Affiliation(s)
- Insa Buers
- 1 Department of General Pediatrics, Muenster University Children's Hospital , Muenster, Germany
| | - Gillian I Rice
- 2 Division of Evolution and Genomic Sciences, Faculty of Biology, Medicine and Health, School of Biological Sciences, University of Manchester , Manchester, United Kingdom
| | - Yanick J Crow
- 2 Division of Evolution and Genomic Sciences, Faculty of Biology, Medicine and Health, School of Biological Sciences, University of Manchester , Manchester, United Kingdom .,3 Laboratory of Neurogenetics and Neuroinflammation , INSERM UMR 1163, Paris, France .,4 Paris Descartes-Sorbonne Paris Cité University , Institute Imagine, Paris, France
| | - Frank Rutsch
- 1 Department of General Pediatrics, Muenster University Children's Hospital , Muenster, Germany
| |
Collapse
|
44
|
Gebhardt A, Laudenbach BT, Pichlmair A. Discrimination of Self and Non-Self Ribonucleic Acids. J Interferon Cytokine Res 2018; 37:184-197. [PMID: 28475460 DOI: 10.1089/jir.2016.0092] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Most virus infections are controlled through the innate and adaptive immune system. A surprisingly limited number of so-called pattern recognition receptors (PRRs) have the ability to sense a large variety of virus infections. The reason for the broad activity of PRRs lies in the ability to recognize viral nucleic acids. These nucleic acids lack signatures that are present in cytoplasmic cellular nucleic acids and thereby marking them as pathogen-derived. Accumulating evidence suggests that these signatures, which are predominantly sensed by a class of PRRs called retinoic acid-inducible gene I (RIG-I)-like receptors and other proteins, are not unique to viruses but rather resemble immature forms of cellular ribonucleic acids generated by cellular polymerases. RIG-I-like receptors, and other cellular antiviral proteins, may therefore have mainly evolved to sense nonprocessed nucleic acids typically generated by primitive organisms and pathogens. This capability has not only implications on induction of antiviral immunity but also on the function of cellular proteins to handle self-derived RNA with stimulatory potential.
Collapse
Affiliation(s)
- Anna Gebhardt
- Innate Immunity Laboratory, Max-Planck Institute of Biochemistry , Munich, Germany
| | | | - Andreas Pichlmair
- Innate Immunity Laboratory, Max-Planck Institute of Biochemistry , Munich, Germany
| |
Collapse
|
45
|
Lee J, Park EB, Min J, Sung SE, Jang Y, Shin JS, Chun D, Kim KH, Hwang J, Lee MK, Go YY, Kwon D, Kim M, Kang SJ, Choi BS. Systematic editing of synthetic RIG-I ligands to produce effective antiviral and anti-tumor RNA immunotherapies. Nucleic Acids Res 2018; 46:1635-1647. [PMID: 29373735 PMCID: PMC5829749 DOI: 10.1093/nar/gky039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 01/17/2018] [Indexed: 12/25/2022] Open
Abstract
Retinoic acid-inducible gene I (RIG-I) recognizes double-stranded viral RNAs (dsRNAs) containing two or three 5' phosphates. A few reports of 5'-PPP-independent RIG-I agonists have emerged, but little is known about the molecular principles underlying their recognition. We recently found that the bent duplex RNA from the influenza A panhandle promoter activates RIG-I even in the absence of a 5'-triphosphate moiety. Here, we report that non-canonical synthetic RNA oligonucleotides containing G-U wobble base pairs that form a bent helix can exert RIG-I-mediated antiviral and anti-tumor effects in a sequence- and site-dependent manner. We present synthetic RNAs that have been systematically modified to enhance their efficacy and we outline the basic principles for engineering RIG-I agonists applicable to immunotherapy.
Collapse
Affiliation(s)
- Janghyun Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Eun-Byeol Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Jiyoun Min
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Si-Eun Sung
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Yejin Jang
- Center for Virus Research and Testing, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, South Korea
| | - Jin Soo Shin
- Center for Virus Research and Testing, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, South Korea
| | - Dongmin Chun
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Ki-Hun Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Jihyun Hwang
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Mi-Kyung Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Yun Young Go
- Center for Virus Research and Testing, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, South Korea
| | - Dohyeong Kwon
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Meehyein Kim
- Center for Virus Research and Testing, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, South Korea
| | - Suk-Jo Kang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Byong-Seok Choi
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| |
Collapse
|
46
|
Chiang JJ, Sparrer KMJ, van Gent M, Lässig C, Huang T, Osterrieder N, Hopfner KP, Gack MU. Viral unmasking of cellular 5S rRNA pseudogene transcripts induces RIG-I-mediated immunity. Nat Immunol 2018; 19:53-62. [PMID: 29180807 PMCID: PMC5815369 DOI: 10.1038/s41590-017-0005-y] [Citation(s) in RCA: 171] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 10/16/2017] [Indexed: 12/25/2022]
Abstract
The sensor RIG-I detects double-stranded RNA derived from RNA viruses. Although RIG-I is also known to have a role in the antiviral response to DNA viruses, physiological RNA species recognized by RIG-I during infection with a DNA virus are largely unknown. Using next-generation RNA sequencing (RNAseq), we found that host-derived RNAs, most prominently 5S ribosomal RNA pseudogene 141 (RNA5SP141), bound to RIG-I during infection with herpes simplex virus 1 (HSV-1). Infection with HSV-1 induced relocalization of RNA5SP141 from the nucleus to the cytoplasm, and virus-induced shutoff of host protein synthesis downregulated the abundance of RNA5SP141-interacting proteins, which allowed RNA5SP141 to bind RIG-I and induce the expression of type I interferons. Silencing of RNA5SP141 strongly dampened the antiviral response to HSV-1 and the related virus Epstein-Barr virus (EBV), as well as influenza A virus (IAV). Our findings reveal that antiviral immunity can be triggered by host RNAs that are unshielded following depletion of their respective binding proteins by the virus.
Collapse
MESH Headings
- Animals
- Cells, Cultured
- Chlorocebus aethiops
- DEAD Box Protein 58/immunology
- DEAD Box Protein 58/metabolism
- Gene Expression/immunology
- HEK293 Cells
- Herpesvirus 1, Human/immunology
- Herpesvirus 1, Human/physiology
- Host-Pathogen Interactions/immunology
- Humans
- Immunity/immunology
- Interferon Type I/genetics
- Interferon Type I/immunology
- Interferon Type I/metabolism
- Mice, Knockout
- Pseudogenes/genetics
- RNA Transport/immunology
- RNA, Ribosomal, 5S/genetics
- RNA, Ribosomal, 5S/immunology
- RNA, Ribosomal, 5S/metabolism
- Receptors, Immunologic
- Vero Cells
Collapse
Affiliation(s)
- Jessica J Chiang
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | | | - Michiel van Gent
- Department of Microbiology, The University of Chicago, Chicago, IL, USA
| | - Charlotte Lässig
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Teng Huang
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
| | | | - Karl-Peter Hopfner
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
- Center for Integrated Protein Science Munich, Munich, Germany
| | - Michaela U Gack
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA.
- Department of Microbiology, The University of Chicago, Chicago, IL, USA.
| |
Collapse
|
47
|
Tan P, He L, Cui J, Qian C, Cao X, Lin M, Zhu Q, Li Y, Xing C, Yu X, Wang HY, Wang RF. Assembly of the WHIP-TRIM14-PPP6C Mitochondrial Complex Promotes RIG-I-Mediated Antiviral Signaling. Mol Cell 2017; 68:293-307.e5. [PMID: 29053956 DOI: 10.1016/j.molcel.2017.09.035] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 08/09/2017] [Accepted: 09/25/2017] [Indexed: 01/30/2023]
Abstract
Mitochondrial antiviral signaling platform protein (MAVS) acts as a central hub for RIG-I receptor proximal signal propagation. However, key components in the assembly of the MAVS mitochondrial platform that promote RIG-I mitochondrial localization and optimal activation are still largely undefined. Employing pooled RNAi and yeast two-hybrid screenings, we report that the mitochondrial adaptor protein tripartite motif (TRIM)14 provides a docking platform for the assembly of the mitochondrial signaling complex required for maximal activation of RIG-I-mediated signaling, consisting of WHIP and protein phosphatase PPP6C. Following viral infection, the ubiquitin-binding domain in WHIP bridges RIG-I with MAVS by binding to polyUb chains of RIG-I at lysine 164. The ATPase domain in WHIP contributes to stabilization of the RIG-I-dsRNA interaction. Moreover, phosphatase PPP6C is responsible for RIG-I dephosphorylation. Together, our findings define the WHIP-TRIM14-PPP6C mitochondrial signalosome required for RIG-I-mediated innate antiviral immunity.
Collapse
Affiliation(s)
- Peng Tan
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, TX 77030, USA; Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Lian He
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, TX 77030, USA
| | - Jun Cui
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, College of Life Sciences, Collaborative Innovation Center of Cancer Medicine, Sun Yat-sen University, Guangzhou 510275, China
| | - Chen Qian
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Xin Cao
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Meng Lin
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Qingyuan Zhu
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Yinyin Li
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, TX 77030, USA; Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Changsheng Xing
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Xiao Yu
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Helen Y Wang
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA.
| | - Rong-Fu Wang
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, TX 77030, USA; Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA; Department of Microbiology and Immunology, Weill Cornell Medical College, Cornell University, New York, NY 10065, USA.
| |
Collapse
|
48
|
Miyamoto M, Komuro A. PACT is required for MDA5-mediated immunoresponses triggered by Cardiovirus infection via interaction with LGP2. Biochem Biophys Res Commun 2017; 494:227-233. [PMID: 29032202 DOI: 10.1016/j.bbrc.2017.10.048] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 10/10/2017] [Indexed: 12/21/2022]
Abstract
Laboratory of genetics and physiology 2 (LGP2) and melanoma differentiation-associated gene 5 (MDA5) cooperatively detect viral RNA in the cytoplasm of Cardiovirus-infected cells and activate innate immune responses. Here, we evaluated whether the double-stranded RNA-binding protein PACT plays a role in this anti-viral response to further elucidate the mechanism. Immunoprecipitation experiments demonstrated that PACT interacts with LGP2 and that this interaction is enhanced by encephalomyocarditis virus (EMCV) infection. In vitro interaction analyses using purified recombinant proteins confirmed that the single-stranded Theiler's murine encephalitis virus genome enhanced the interaction between LGP2 and PACT. Small interfering RNA knockdown experiments further indicated that PACT is required for Cardiovirus-triggered interferon responses. To support this functional interaction with LGP2, overexpressed PACT was shown to enhance EMCV-triggered interferon promoter activity only when LGP2 and MDA5 were co-expressed but not when MDA5 is expressed alone. Together, our findings indicate a possible role of PACT in regulating the Cardiovirus-triggered immune responses mediated by MDA5 and LGP2, which opens the door to novel therapeutic strategies in interferon-related autoimmune diseases and cancer.
Collapse
Affiliation(s)
- Masahiko Miyamoto
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata 956-8603, Japan
| | - Akihiko Komuro
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata 956-8603, Japan.
| |
Collapse
|
49
|
Andreeva L, Hiller B, Kostrewa D, Lässig C, de Oliveira Mann CC, Jan Drexler D, Maiser A, Gaidt M, Leonhardt H, Hornung V, Hopfner KP. cGAS senses long and HMGB/TFAM-bound U-turn DNA by forming protein-DNA ladders. Nature 2017; 549:394-398. [PMID: 28902841 DOI: 10.1038/nature23890] [Citation(s) in RCA: 323] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 07/31/2017] [Indexed: 12/28/2022]
Abstract
Cytosolic DNA arising from intracellular pathogens triggers a powerful innate immune response. It is sensed by cyclic GMP-AMP synthase (cGAS), which elicits the production of type I interferons by generating the second messenger 2'3'-cyclic-GMP-AMP (cGAMP). Endogenous nuclear or mitochondrial DNA can also be sensed by cGAS under certain conditions, resulting in sterile inflammation. The cGAS dimer binds two DNA ligands shorter than 20 base pairs side-by-side, but 20-base-pair DNA fails to activate cGAS in vivo and is a poor activator in vitro. Here we show that cGAS is activated in a strongly DNA length-dependent manner both in vitro and in human cells. We also show that cGAS dimers form ladder-like networks with DNA, leading to cooperative sensing of DNA length: assembly of the pioneering cGAS dimer between two DNA molecules is ineffective; but, once formed, it prearranges the flanking DNA to promote binding of subsequent cGAS dimers. Remarkably, bacterial and mitochondrial nucleoid proteins HU and mitochondrial transcription factor A (TFAM), as well as high-mobility group box 1 protein (HMGB1), can strongly stimulate long DNA sensing by cGAS. U-turns and bends in DNA induced by these proteins pre-structure DNA to nucleate cGAS dimers. Our results suggest a nucleation-cooperativity-based mechanism for sensitive detection of mitochondrial DNA and pathogen genomes, and identify HMGB/TFAM proteins as DNA-structuring host factors. They provide an explanation for the peculiar cGAS dimer structure and suggest that cGAS preferentially binds incomplete nucleoid-like structures or bent DNA.
Collapse
Affiliation(s)
- Liudmila Andreeva
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Björn Hiller
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Dirk Kostrewa
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Charlotte Lässig
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Carina C de Oliveira Mann
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - David Jan Drexler
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Andreas Maiser
- Department of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Moritz Gaidt
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Heinrich Leonhardt
- Department of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany.,Center for Integrated Protein Science Munich, 81377 Munich, Germany
| | - Veit Hornung
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Center for Integrated Protein Science Munich, 81377 Munich, Germany
| | - Karl-Peter Hopfner
- Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.,Center for Integrated Protein Science Munich, 81377 Munich, Germany
| |
Collapse
|
50
|
Lu C, MacDougall M. RIG-I-Like Receptor Signaling in Singleton-Merten Syndrome. Front Genet 2017; 8:118. [PMID: 28955379 PMCID: PMC5600918 DOI: 10.3389/fgene.2017.00118] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 08/29/2017] [Indexed: 12/12/2022] Open
Abstract
Singleton-Merten syndrome (SMS) is an autosomal dominant, multi-system innate immune disorder characterized by early and severe aortic and valvular calcification, dental and skeletal abnormalities, psoriasis, glaucoma, and other varying clinical findings. Recently we identified a specific gain-of-function mutation in IFIH1, interferon induced with helicase C domain 1, segregated with this disease. SMS disease without hallmark dental anomalies, termed atypical SMS, has recently been reported caused by variants in DDX58, DEXD/H-box helicase 58. IFIH1 and DDX58 encode retinoic acid-inducible gene I (RIG-I)-like receptors family members melanoma differentiation-associated gene 5 and RIG-I, respectively. These cytosolic pattern recognition receptors function in viral RNA detection initiating an innate immune response through independent pathways that promote type I and type III interferon expression and proinflammatory cytokines. In this review, we focus on SMS as an innate immune disorder summarizing clinical features, molecular aspects of the pathogenetic pathway and discussing underlying mechanisms of the disease.
Collapse
Affiliation(s)
- Changming Lu
- Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, BirminghamAL, United States
| | - Mary MacDougall
- Faculty of Dentistry, University of British Columbia, VancouverBC, Canada
| |
Collapse
|