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Cottrell KA, Ryu S, Donelick H, Mai H, Pierce JR, Bass BL, Weber JD. Activation of PKR by a short-hairpin RNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.08.592371. [PMID: 38766230 PMCID: PMC11100704 DOI: 10.1101/2024.05.08.592371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Recognition of viral infection often relies on the detection of double-stranded RNA (dsRNA), a process that is conserved in many different organisms. In mammals, proteins such as MDA5, RIG-I, OAS, and PKR detect viral dsRNA, but struggle to differentiate between viral and endogenous dsRNA. This study investigates an shRNA targeting DDX54's potential to activate PKR, a key player in the immune response to dsRNA. Knockdown of DDX54 by a specific shRNA induced robust PKR activation in human cells, even when DDX54 is overexpressed, suggesting an off-target mechanism. Activation of PKR by the shRNA was enhanced by knockdown of ADAR1, a dsRNA binding protein that suppresses PKR activation, indicating a dsRNA-mediated mechanism. In vitro assays confirmed direct PKR activation by the shRNA. These findings emphasize the need for rigorous controls and alternative methods to validate gene function and minimize unintended immune pathway activation.
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Affiliation(s)
- Kyle A. Cottrell
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, Saint Louis, Missouri, USA
- ICCE Institute, Washington University School of Medicine, Saint Louis, Missouri, USA
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
| | - Sua Ryu
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, Saint Louis, Missouri, USA
- ICCE Institute, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Helen Donelick
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Hung Mai
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, Saint Louis, Missouri, USA
- ICCE Institute, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Jackson R. Pierce
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
| | - Brenda L. Bass
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Jason D. Weber
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Department of Biology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, Missouri, USA
- ICCE Institute, Washington University School of Medicine, Saint Louis, Missouri, USA
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2
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Manjunath L, Oh S, Ortega P, Bouin A, Bournique E, Sanchez A, Martensen PM, Auerbach AA, Becker JT, Seldin M, Harris RS, Semler BL, Buisson R. APOBEC3B drives PKR-mediated translation shutdown and protects stress granules in response to viral infection. Nat Commun 2023; 14:820. [PMID: 36781883 PMCID: PMC9925369 DOI: 10.1038/s41467-023-36445-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/31/2023] [Indexed: 02/15/2023] Open
Abstract
Double-stranded RNA produced during viral replication and transcription activates both protein kinase R (PKR) and ribonuclease L (RNase L), which limits viral gene expression and replication through host shutoff of translation. In this study, we find that APOBEC3B forms a complex with PABPC1 to stimulate PKR and counterbalances the PKR-suppressing activity of ADAR1 in response to infection by many types of viruses. This leads to translational blockage and the formation of stress granules. Furthermore, we show that APOBEC3B localizes to stress granules through the interaction with PABPC1. APOBEC3B facilitates the formation of protein-RNA condensates with stress granule assembly factor (G3BP1) by protecting mRNA associated with stress granules from RNAse L-induced RNA cleavage during viral infection. These results not only reveal that APOBEC3B is a key regulator of different steps of the innate immune response throughout viral infection but also highlight an alternative mechanism by which APOBEC3B can impact virus replication without editing viral genomes.
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Affiliation(s)
- Lavanya Manjunath
- Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, CA, USA
- Center for Virus Research, University of California Irvine, Irvine, CA, USA
- Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California Irvine, Irvine, CA, USA
| | - Sunwoo Oh
- Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, CA, USA
- Center for Virus Research, University of California Irvine, Irvine, CA, USA
- Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California Irvine, Irvine, CA, USA
| | - Pedro Ortega
- Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, CA, USA
- Center for Virus Research, University of California Irvine, Irvine, CA, USA
- Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California Irvine, Irvine, CA, USA
| | - Alexis Bouin
- Center for Virus Research, University of California Irvine, Irvine, CA, USA
- Department of Microbiology & Molecular Genetics, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Elodie Bournique
- Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, CA, USA
- Center for Virus Research, University of California Irvine, Irvine, CA, USA
- Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California Irvine, Irvine, CA, USA
| | - Ambrocio Sanchez
- Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, CA, USA
- Center for Virus Research, University of California Irvine, Irvine, CA, USA
- Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California Irvine, Irvine, CA, USA
| | - Pia Møller Martensen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - Ashley A Auerbach
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX, USA
- Institute for Molecular Virology, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Jordan T Becker
- Institute for Molecular Virology, University of Minnesota - Twin Cities, Minneapolis, MN, USA
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Marcus Seldin
- Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, CA, USA
- Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California Irvine, Irvine, CA, USA
| | - Reuben S Harris
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX, USA
- Howard Hughes Medical Institute, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Bert L Semler
- Center for Virus Research, University of California Irvine, Irvine, CA, USA
- Department of Microbiology & Molecular Genetics, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Rémi Buisson
- Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, CA, USA.
- Center for Virus Research, University of California Irvine, Irvine, CA, USA.
- Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California Irvine, Irvine, CA, USA.
- Department of Pharmaceutical Sciences, School of Pharmacy & Pharmaceutical Sciences, University of California Irvine, Irvine, CA, USA.
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3
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Ha T, DiPrima M, Koparde V, Jailwala P, Ohnuki H, Feng JX, Palangat M, Larson D, Tosato G. Antisense transcription from lentiviral gene targeting linked to an integrated stress response in colorectal cancer cells. MOLECULAR THERAPY - NUCLEIC ACIDS 2022; 28:877-891. [PMID: 35694213 PMCID: PMC9163427 DOI: 10.1016/j.omtn.2022.05.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 05/12/2022] [Indexed: 11/10/2022]
Abstract
Advances in gene therapy research have resulted in the successful development of new therapies for clinical use. Here, we explored a gene targeting approach to deplete ephrinB2 from colorectal cancer cells using an inducible lentiviral vector. EphrinB2, a transmembrane ephrin ligand, promotes colorectal cancer cell growth and viability and predicts poor patient survival when expressed at high levels in colorectal cancer tissues. We discovered that lentiviral vector integration and expression in the host DNA frequently drive divergent host gene transcription, generating antisense reads coupled with splicing events and generation of chimeric vector/host transcripts. Antisense transcription of host DNA was linked to development of an integrated stress response and cell death. Despite recent successes, off-target effects remain a concern in genetic medicine. Our results provide evidence that divergent gene transcription is a previously unrecognized off-target effect of lentiviral vector integration with built-in properties for regulation of gene expression.
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Liu CX, Guo SK, Nan F, Xu YF, Yang L, Chen LL. RNA circles with minimized immunogenicity as potent PKR inhibitors. Mol Cell 2021; 82:420-434.e6. [PMID: 34951963 DOI: 10.1016/j.molcel.2021.11.019] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 08/31/2021] [Accepted: 11/17/2021] [Indexed: 12/16/2022]
Abstract
Exon back-splicing-generated circular RNAs, as a group, can suppress double-stranded RNA (dsRNA)-activated protein kinase R (PKR) in cells. We have sought to synthesize immunogenicity-free, short dsRNA-containing RNA circles as PKR inhibitors. Here, we report that RNA circles synthesized by permuted self-splicing thymidylate synthase (td) introns from T4 bacteriophage or by Anabaena pre-tRNA group I intron could induce an immune response. Autocatalytic splicing introduces ∼74 nt td or ∼186 nt Anabaena extraneous fragments that can distort the folding status of original circular RNAs or form structures themselves to provoke innate immune responses. In contrast, synthesized RNA circles produced by T4 RNA ligase without extraneous fragments exhibit minimized immunogenicity. Importantly, directly ligated circular RNAs that form short dsRNA regions efficiently suppress PKR activation 103- to 106-fold higher than reported chemical compounds C16 and 2-AP, highlighting the future use of circular RNAs as potent inhibitors for diseases related to PKR overreaction.
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Affiliation(s)
- Chu-Xiao Liu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Si-Kun Guo
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Fang Nan
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Yi-Feng Xu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Li Yang
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China; School of Life Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai 201210, China
| | - Ling-Ling Chen
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China; School of Life Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai 201210, China; School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China.
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5
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Sajid MI, Moazzam M, Kato S, Yeseom Cho K, Tiwari RK. Overcoming Barriers for siRNA Therapeutics: From Bench to Bedside. Pharmaceuticals (Basel) 2020; 13:E294. [PMID: 33036435 PMCID: PMC7600125 DOI: 10.3390/ph13100294] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/29/2020] [Accepted: 10/02/2020] [Indexed: 12/16/2022] Open
Abstract
The RNA interference (RNAi) pathway possesses immense potential in silencing any gene in human cells. Small interfering RNA (siRNA) can efficiently trigger RNAi silencing of specific genes. FDA Approval of siRNA therapeutics in recent years garnered a new hope in siRNA therapeutics. However, their therapeutic use is limited by several challenges. siRNAs, being negatively charged, are membrane-impermeable and highly unstable in the systemic circulation. In this review, we have comprehensively discussed the extracellular barriers, including enzymatic degradation of siRNAs by serum endonucleases and RNAases, rapid renal clearance, membrane impermeability, and activation of the immune system. Besides, we have thoroughly described the intracellular barriers such as endosomal trap and off-target effects of siRNAs. Moreover, we have reported most of the strategies and techniques in overcoming these barriers, followed by critical comments in translating these molecules from bench to bedside.
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Affiliation(s)
- Muhammad Imran Sajid
- Center for Targeted Drug Delivery, Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Harry and Diane Rinker Health Science Campus, Irvine, CA 92618, USA; (M.I.S.); (S.K.); (K.Y.C.)
- Faculty of Pharmacy, University of Central Punjab, Lahore 54000, Pakistan;
| | - Muhammad Moazzam
- Faculty of Pharmacy, University of Central Punjab, Lahore 54000, Pakistan;
| | - Shun Kato
- Center for Targeted Drug Delivery, Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Harry and Diane Rinker Health Science Campus, Irvine, CA 92618, USA; (M.I.S.); (S.K.); (K.Y.C.)
| | - Kayley Yeseom Cho
- Center for Targeted Drug Delivery, Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Harry and Diane Rinker Health Science Campus, Irvine, CA 92618, USA; (M.I.S.); (S.K.); (K.Y.C.)
| | - Rakesh Kumar Tiwari
- Center for Targeted Drug Delivery, Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Harry and Diane Rinker Health Science Campus, Irvine, CA 92618, USA; (M.I.S.); (S.K.); (K.Y.C.)
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Eiermann N, Haneke K, Sun Z, Stoecklin G, Ruggieri A. Dance with the Devil: Stress Granules and Signaling in Antiviral Responses. Viruses 2020; 12:v12090984. [PMID: 32899736 PMCID: PMC7552005 DOI: 10.3390/v12090984] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/31/2020] [Accepted: 08/31/2020] [Indexed: 02/07/2023] Open
Abstract
Cells have evolved highly specialized sentinels that detect viral infection and elicit an antiviral response. Among these, the stress-sensing protein kinase R, which is activated by double-stranded RNA, mediates suppression of the host translation machinery as a strategy to limit viral replication. Non-translating mRNAs rapidly condensate by phase separation into cytosolic stress granules, together with numerous RNA-binding proteins and components of signal transduction pathways. Growing evidence suggests that the integrated stress response, and stress granules in particular, contribute to antiviral defense. This review summarizes the current understanding of how stress and innate immune signaling act in concert to mount an effective response against virus infection, with a particular focus on the potential role of stress granules in the coordination of antiviral signaling cascades.
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Affiliation(s)
- Nina Eiermann
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany; (N.E.); (K.H.); (G.S.)
| | - Katharina Haneke
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany; (N.E.); (K.H.); (G.S.)
| | - Zhaozhi Sun
- Department of Infectious Diseases, Molecular Virology, Center for Integrative Infectious Disease Research (CIID), University of Heidelberg, 69120 Heidelberg, Germany;
| | - Georg Stoecklin
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany; (N.E.); (K.H.); (G.S.)
| | - Alessia Ruggieri
- Department of Infectious Diseases, Molecular Virology, Center for Integrative Infectious Disease Research (CIID), University of Heidelberg, 69120 Heidelberg, Germany;
- Correspondence:
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Abstract
Protein kinase R (PKR) is a key antiviral component of the innate immune pathway and is activated by viral double-stranded RNAs (dsRNAs). Adenovirus-associated RNA 1 (VAI) is an abundant, noncoding viral RNA that functions as a decoy by binding PKR but not inducing activation, thereby inhibiting the antiviral response. In VAI, coaxial stacking produces an extended helix that mediates high-affinity PKR binding but is too short to result in activation. Like adenovirus, Epstein-Barr virus produces high concentrations of a noncoding RNA, EBER1. Here, we compare interactions of PKR with VAI and EBER1 and present a structural model of EBER1. Both RNAs function as inhibitors of dsRNA-mediated PKR activation. However, EBER1 weakly activates PKR whereas VAI does not. PKR binds EBER1 more weakly than VAI. Assays at physiological ion concentrations indicate that both RNAs can accommodate two PKR monomers and induce PKR dimerization. A structural model of EBER1 was obtained using constraints derived from chemical structure probing and small-angle X-ray scattering experiments. The central stem of EBER1 coaxially stacks with stem loop 4 and stem loop 1 to form an extended RNA duplex of ∼32 bp that binds PKR and promotes activation. Our observations that EBER1 binds PKR much more weakly than VAI and exhibits weak PKR activation suggest that EBER1 is less well suited to function as an RNA decoy.
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Wu MZ, Asahara H, Tzertzinis G, Roy B. Synthesis of low immunogenicity RNA with high-temperature in vitro transcription. RNA (NEW YORK, N.Y.) 2020; 26:345-360. [PMID: 31900329 PMCID: PMC7025508 DOI: 10.1261/rna.073858.119] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/30/2019] [Indexed: 05/26/2023]
Abstract
The use of synthetic RNA for therapeutics requires that the in vitro synthesis process be robust and efficient. The technology used for the synthesis of these in vitro-transcribed RNAs, predominantly using phage RNA polymerases (RNAPs), is well established. However, transcripts synthesized with RNAPs are known to display an immune-stimulatory activity in vivo that is often undesirable. Previous studies have identified double-stranded RNA (dsRNA), a major by-product of the in vitro transcription (IVT) process, as a trigger of cellular immune responses. Here we describe the characterization of a high-temperature IVT process using thermostable T7 RNAPs to synthesize functional mRNAs that demonstrate reduced immunogenicity without the need for a post-synthesis purification step. We identify features that drive the production of two kinds of dsRNA by-products-one arising from 3' extension of the run-off product and one formed by the production of antisense RNAs-and demonstrate that at a high temperature, T7 RNAP has reduced 3'-extension of the run-off product. We show that template-encoded poly(A) tailing does not affect 3'-extension but reduces the formation of the antisense RNA by-products. Combining high-temperature IVT with template-encoded poly(A) tailing prevents the formation of both kinds of dsRNA by-products generating functional mRNAs with reduced immunogenicity.
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Affiliation(s)
- Monica Z Wu
- RNA and Genome Editing, New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Haruichi Asahara
- RNA and Genome Editing, New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - George Tzertzinis
- RNA and Genome Editing, New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Bijoyita Roy
- RNA and Genome Editing, New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
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Darweesh M, Kamel W, Gavrilin MA, Akusjärvi G, Svensson C. Adenovirus VA RNAI Blocks ASC Oligomerization and Inhibits NLRP3 Inflammasome Activation. Front Immunol 2019; 10:2791. [PMID: 31849970 PMCID: PMC6901988 DOI: 10.3389/fimmu.2019.02791] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 11/14/2019] [Indexed: 01/10/2023] Open
Abstract
Virus infected immune cells can rapidly respond to the invader by activating the inflammasome and as a consequence release proinflammatory cytokines and eventually die by pyroptosis. In human adenovirus-5 (Ad5) infected THP-1 cells, inhibition of NLRP3 inflammasome activation was demonstrated by a decreased secretion of HMGB1 and matured forms of caspase-1and IL-1ß. An Ad5 mutant virus defective in expression of the non-coding VA RNAI failed to inhibit the NLRP3 inflammasome and in addition displayed formation of ASC specks and increased cell lysis. Importantly, in vitro synthesized VA RNAI was able to inhibit the NLRP3 inflammasome activity in THP-1 cells in the absence of an Ad5 infection, suggesting that VA RNAI binding to PKR and blocking its function is sufficient for inhibition of the NLRP3 inflammasome. Although the inhibition of NLRP3 inflammasome activation required the phylogenetically conserved base paired tetranucleotide sequence in the central stem of VA RNAI, we demonstrate that PKR binding to VA RNAI primarily protected the apical stem, but not the tetranucleotide sequence itself. VA RNAI did not influence the interaction between PKR and NLRP3. In contrast, we describe a novel interaction between PKR and ASC and further show that VA RNAI inhibited ASC phosphorylation and oligomerization. Collectively, our results indicate a novel role for Ad5 VA RNAI as an inhibitor of NLRP3 inflammasome activation by targeting the cellular pro-inflammatory protein PKR.
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Affiliation(s)
- Mahmoud Darweesh
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.,Department of Microbiology and Immunology, Al-Azhr University, Assiut, Egypt
| | - Wael Kamel
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Mikhail A Gavrilin
- Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
| | - Göran Akusjärvi
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Catharina Svensson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
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