1
|
Jin B, Moududee SA, Ge D, Zhou P, Wang AR, Liu YZ, You Z. SCF FBXW11 Complex Targets Interleukin-17 Receptor A for Ubiquitin-Proteasome-Mediated Degradation. Biomedicines 2024; 12:755. [PMID: 38672111 PMCID: PMC11047997 DOI: 10.3390/biomedicines12040755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/23/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Interleukin-17 (IL-17) is a pro-inflammatory cytokine that participates in innate and adaptive immune responses and plays an important role in host defense, autoimmune diseases, tissue regeneration, metabolic regulation, and tumor progression. Post-translational modifications (PTMs) are crucial for protein function, stability, cellular localization, cellular transduction, and cell death. However, PTMs of IL-17 receptor A (IL-17RA) have not been investigated. Here, we show that human IL-17RA was targeted by F-box and WD repeat domain-containing 11 (FBXW11) for ubiquitination, followed by proteasome-mediated degradation. We used bioinformatics tools and biochemical techniques to determine that FBXW11 ubiquitinated IL-17RA through a lysine 27-linked polyubiquitin chain, targeting IL-17RA for proteasomal degradation. Domain 665-804 of IL-17RA was critical for interaction with FBXW11 and subsequent ubiquitination. Our study demonstrates that FBXW11 regulates IL-17 signaling pathways at the IL-17RA level.
Collapse
Affiliation(s)
- Ben Jin
- Southeast Louisiana Veterans Health Care System, New Orleans, LA 70112, USA; (B.J.); (S.A.M.)
- Department of Structural & Cellular Biology, Tulane University, New Orleans, LA 70112, USA
| | - Sayed Ala Moududee
- Southeast Louisiana Veterans Health Care System, New Orleans, LA 70112, USA; (B.J.); (S.A.M.)
- Department of Structural & Cellular Biology, Tulane University, New Orleans, LA 70112, USA
| | - Dongxia Ge
- Department of Orthopaedic Surgery, Tulane University, New Orleans, LA 70112, USA;
| | - Pengbo Zhou
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY 10065, USA;
| | - Alun R. Wang
- Department of Pathology and Laboratory Medicine, Tulane University, New Orleans, LA 70112, USA;
| | - Yao-Zhong Liu
- Department of Biostatistics and Data Science, Tulane University, New Orleans, LA 70112, USA;
| | - Zongbing You
- Southeast Louisiana Veterans Health Care System, New Orleans, LA 70112, USA; (B.J.); (S.A.M.)
- Department of Structural & Cellular Biology, Tulane University, New Orleans, LA 70112, USA
- Department of Orthopaedic Surgery, Tulane University, New Orleans, LA 70112, USA;
- Tulane Cancer Center and Louisiana Cancer Research Consortium, Tulane University, New Orleans, LA 70112, USA
- Tulane Center for Stem Cell Research and Regenerative Medicine, Tulane University, New Orleans, LA 70112, USA
- Tulane Center for Aging, Tulane University, New Orleans, LA 70112, USA
| |
Collapse
|
2
|
Petraccione K, Ali MGH, Cyr N, Wahba HM, Stocker T, Akhrymuk M, Akhrymuk I, Panny L, Bracci N, Cafaro R, Sastre D, Silberfarb A, O’Maille P, Omichinski J, Kehn-Hall K. An LIR motif in the Rift Valley fever virus NSs protein is critical for the interaction with LC3 family members and inhibition of autophagy. PLoS Pathog 2024; 20:e1012093. [PMID: 38512999 PMCID: PMC10986958 DOI: 10.1371/journal.ppat.1012093] [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: 11/28/2023] [Revised: 04/02/2024] [Accepted: 03/04/2024] [Indexed: 03/23/2024] Open
Abstract
Rift Valley fever virus (RVFV) is a viral zoonosis that causes severe disease in ruminants and humans. The nonstructural small (NSs) protein is the primary virulence factor of RVFV that suppresses the host's antiviral innate immune response. Bioinformatic analysis and AlphaFold structural modeling identified four putative LC3-interacting regions (LIR) motifs (NSs 1-4) in the RVFV NSs protein, which suggest that NSs interacts with the host LC3-family proteins. Using, isothermal titration calorimetry, X-ray crystallography, co-immunoprecipitation, and co-localization experiments, the C-terminal LIR motif (NSs4) was confirmed to interact with all six human LC3 proteins. Phenylalanine at position 261 (F261) within NSs4 was found to be critical for the interaction of NSs with LC3, retention of LC3 in the nucleus, as well as the inhibition of autophagy in RVFV infected cells. These results provide mechanistic insights into the ability of RVFV to overcome antiviral autophagy through the interaction of NSs with LC3 proteins.
Collapse
Affiliation(s)
- Kaylee Petraccione
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Mohamed G. H. Ali
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec, Canada
- Department of Biochemistry, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
| | - Normand Cyr
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec, Canada
| | - Haytham M. Wahba
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec, Canada
- Department of Biochemistry, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
| | - Timothy Stocker
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Maryna Akhrymuk
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Ivan Akhrymuk
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Lauren Panny
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Nicole Bracci
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Raphaël Cafaro
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec, Canada
- Department of Biochemistry, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
| | - Danuta Sastre
- Biosciences Division, SRI International, Menlo Park, California, United States of America
| | - Andrew Silberfarb
- Artificial Intelligence Center, SRI International, Menlo Park, California, United States of America
| | - Paul O’Maille
- Biosciences Division, SRI International, Menlo Park, California, United States of America
| | - James Omichinski
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec, Canada
| | - Kylene Kehn-Hall
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| |
Collapse
|
3
|
Bostedt L, Fénéant L, Leske A, Holzerland J, Günther K, Waßmann I, Bohn P, Groseth A. Alternative translation contributes to the generation of a cytoplasmic subpopulation of the Junín virus nucleoprotein that inhibits caspase activation and innate immunity. J Virol 2024; 98:e0197523. [PMID: 38294249 PMCID: PMC10878266 DOI: 10.1128/jvi.01975-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 01/03/2024] [Indexed: 02/01/2024] Open
Abstract
The highly pathogenic arenavirus, Junín virus (JUNV), expresses three truncated alternative isoforms of its nucleoprotein (NP), i.e., NP53kD, NP47kD, and NP40kD. While both NP47kD and NP40kD have been previously shown to be products of caspase cleavage, here, we show that expression of the third isoform NP53kD is due to alternative in-frame translation from M80. Based on this information, we were able to generate recombinant JUNVs lacking each of these isoforms. Infection with these mutants revealed that, while all three isoforms contribute to the efficient control of caspase activation, NP40kD plays the predominant role. In contrast to full-length NP (i.e., NP65kD), which is localized to inclusion bodies, where viral RNA synthesis takes place, the loss of portions of the N-terminal coiled-coil region in these isoforms leads to a diffuse cytoplasmic distribution and a loss of function in viral RNA synthesis. Nonetheless, NP53kD, NP47kD, and NP40kD all retain robust interferon antagonistic and 3'-5' exonuclease activities. We suggest that the altered localization of these NP isoforms allows them to be more efficiently targeted by activated caspases for cleavage as decoy substrates, and to be better positioned to degrade viral double-stranded (ds)RNA species that accumulate in the cytoplasm during virus infection and/or interact with cytosolic RNA sensors, thereby limiting dsRNA-mediated innate immune responses. Taken together, this work provides insight into the mechanism by which JUNV leverages apoptosis during infection to generate biologically distinct pools of NP and contributes to our understanding of the expression and biological relevance of alternative protein isoforms during virus infection.IMPORTANCEA limited coding capacity means that RNA viruses need strategies to diversify their proteome. The nucleoprotein (NP) of the highly pathogenic arenavirus Junín virus (JUNV) produces three N-terminally truncated isoforms: two (NP47kD and NP40kD) are known to be produced by caspase cleavage, while, here, we show that NP53kD is produced by alternative translation initiation. Recombinant JUNVs lacking individual NP isoforms revealed that all three isoforms contribute to inhibiting caspase activation during infection, but cleavage to generate NP40kD makes the biggest contribution. Importantly, all three isoforms retain their ability to digest double-stranded (ds)RNA and inhibit interferon promoter activation but have a diffuse cytoplasmic distribution. Given the cytoplasmic localization of both aberrant viral dsRNAs, as well as dsRNA sensors and many other cellular components of innate immune activation pathways, we suggest that the generation of NP isoforms not only contributes to evasion of apoptosis but also robust control of the antiviral response.
Collapse
Affiliation(s)
- Linus Bostedt
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Lucie Fénéant
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Anne Leske
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Julia Holzerland
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Karla Günther
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Irke Waßmann
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Patrick Bohn
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Allison Groseth
- Laboratory for Arenavirus Biology, Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| |
Collapse
|
4
|
Corneillie L, Lemmens I, Weening K, De Meyer A, Van Houtte F, Tavernier J, Meuleman P. Virus-Host Protein Interaction Network of the Hepatitis E Virus ORF2-4 by Mammalian Two-Hybrid Assays. Viruses 2023; 15:2412. [PMID: 38140653 PMCID: PMC10748205 DOI: 10.3390/v15122412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Throughout their life cycle, viruses interact with cellular host factors, thereby influencing propagation, host range, cell tropism and pathogenesis. The hepatitis E virus (HEV) is an underestimated RNA virus in which knowledge of the virus-host interaction network to date is limited. Here, two related high-throughput mammalian two-hybrid approaches (MAPPIT and KISS) were used to screen for HEV-interacting host proteins. Promising hits were examined on protein function, involved pathway(s), and their relation to other viruses. We identified 37 ORF2 hits, 187 for ORF3 and 91 for ORF4. Several hits had functions in the life cycle of distinct viruses. We focused on SHARPIN and RNF5 as candidate hits for ORF3, as they are involved in the RLR-MAVS pathway and interferon (IFN) induction during viral infections. Knocking out (KO) SHARPIN and RNF5 resulted in a different IFN response upon ORF3 transfection, compared to wild-type cells. Moreover, infection was increased in SHARPIN KO cells and decreased in RNF5 KO cells. In conclusion, MAPPIT and KISS are valuable tools to study virus-host interactions, providing insights into the poorly understood HEV life cycle. We further provide evidence for two identified hits as new host factors in the HEV life cycle.
Collapse
Affiliation(s)
- Laura Corneillie
- Laboratory of Liver Infectious Diseases, Department of Diagnostic Sciences, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| | - Irma Lemmens
- VIB-UGent Center for Medical Biotechnology, Department of Biomolecular Medicine, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| | - Karin Weening
- Laboratory of Liver Infectious Diseases, Department of Diagnostic Sciences, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| | - Amse De Meyer
- Laboratory of Liver Infectious Diseases, Department of Diagnostic Sciences, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| | - Freya Van Houtte
- Laboratory of Liver Infectious Diseases, Department of Diagnostic Sciences, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| | - Jan Tavernier
- VIB-UGent Center for Medical Biotechnology, Department of Biomolecular Medicine, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| | - Philip Meuleman
- Laboratory of Liver Infectious Diseases, Department of Diagnostic Sciences, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium
| |
Collapse
|
5
|
Balaraman V, Indran SV, Li Y, Meekins DA, Jakkula LUMR, Liu H, Hays MP, Souza-Neto JA, Gaudreault NN, Hardwidge PR, Wilson WC, Weber F, Richt JA. Identification of Host Factors for Rift Valley Fever Phlebovirus. Viruses 2023; 15:2251. [PMID: 38005928 PMCID: PMC10675714 DOI: 10.3390/v15112251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/26/2023] [Accepted: 10/30/2023] [Indexed: 11/26/2023] Open
Abstract
Rift Valley fever phlebovirus (RVFV) is a zoonotic pathogen that causes Rift Valley fever (RVF) in livestock and humans. Currently, there is no licensed human vaccine or antiviral drug to control RVF. Although multiple species of animals and humans are vulnerable to RVFV infection, host factors affecting susceptibility are not well understood. To identify the host factors or genes essential for RVFV replication, we conducted CRISPR-Cas9 knockout screening in human A549 cells. We then validated the putative genes using siRNA-mediated knock-downs and CRISPR-Cas9-mediated knock-out studies. The role of a candidate gene in the virus replication cycle was assessed by measuring intracellular viral RNA accumulation, and the virus titers were analyzed using plaque assay or TCID50 assay. We identified approximately 900 genes with potential involvement in RVFV infection and replication. Further evaluation of the effect of six genes on viral replication using siRNA-mediated knock-downs revealed that silencing two genes (WDR7 and LRP1) significantly impaired RVFV replication. For further analysis, we focused on the WDR7 gene since the role of the LRP1 gene in RVFV replication was previously described in detail. WDR7 knockout A549 cell lines were generated and used to dissect the effect of WRD7 on a bunyavirus, RVFV, and an orthobunyavirus, La Crosse encephalitis virus (LACV). We observed significant effects of WDR7 knockout cells on both intracellular RVFV RNA levels and viral titers. At the intracellular RNA level, WRD7 affected RVFV replication at a later phase of its replication cycle (24 h) when compared with the LACV replication, which was affected in an earlier replication phase (12 h). In summary, we identified WDR7 as an essential host factor for the replication of two different viruses, RVFV and LACV, both of which belong to the Bunyavirales order. Future studies will investigate the mechanistic role through which WDR7 facilitates phlebovirus replication.
Collapse
Affiliation(s)
- Velmurugan Balaraman
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Sabarish V. Indran
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Yonghai Li
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - David A. Meekins
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Laxmi U. M. R. Jakkula
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Heidi Liu
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Micheal P. Hays
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Jayme A. Souza-Neto
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Natasha N. Gaudreault
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - Philip R. Hardwidge
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| | - William C. Wilson
- Foreign Arthropod-Borne Animal Diseases Research Unit, United States Department of Agriculture, National Bio and Agro-Defense Facility, Agricultural Research Service, 1980 Denison Ave, Manhattan, KS 66506, USA
| | - Friedemann Weber
- Institute for Virology, FB10—Veterinary Medicine, Justus-Liebig University, 35392 Giessen, Germany
| | - Juergen A. Richt
- Center of Excellence for Emerging and Zoonotic Animal Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS 66506, USA
| |
Collapse
|
6
|
Ito T, Wuerth JD, Weber F. Protection of eIF2B from inhibitory phosphorylated eIF2: A viral strategy to maintain mRNA translation during the PKR-triggered integrated stress response. J Biol Chem 2023; 299:105287. [PMID: 37742919 PMCID: PMC10616414 DOI: 10.1016/j.jbc.2023.105287] [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: 04/11/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/26/2023] Open
Abstract
The integrated stress response (ISR) protects cells from a variety of insults. Once elicited (e.g., by virus infections), it eventually leads to the block of mRNA translation. Central to the ISR are the interactions between translation initiation factors eIF2 and eIF2B. Under normal conditions, eIF2 drives the initiation of protein synthesis through hydrolysis of GTP, which becomes replenished by the guanine nucleotide exchange factor eIF2B. The antiviral branch of the ISR is activated by the RNA-activated kinase PKR which phosphorylates eIF2, thereby converting it into an eIF2B inhibitor. Here, we describe the recently solved structures of eIF2B in complex with eIF2 and a novel escape strategy used by viruses. While unphosphorylated eIF2 interacts with eIF2B in its "productive" conformation, phosphorylated eIF2 [eIF2(αP)] engages a different binding cavity on eIF2B and forces it into the "nonproductive" conformation that prohibits guanine nucleotide exchange factor activity. It is well established that viruses express so-called PKR antagonists that interfere with double-strand RNA, PKR itself, or eIF2. However recently, three taxonomically unrelated viruses were reported to encode antagonists targeting eIF2B instead. For one antagonist, the S segment nonstructural protein of Sandfly fever Sicilian virus, atomic structures showed that it occupies the eIF2(αP)-binding cavity on eIF2B without imposing a switch to the nonproductive conformation. S segment nonstructural protein thus antagonizes the activity of PKR by protecting eIF2B from inhibition by eIF2(αP). As the ISR and specifically eIF2B are central to neuroprotection and a wide range of genetic and age-related diseases, these developments may open new possibilities for treatments.
Collapse
Affiliation(s)
- Takuhiro Ito
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Yokohama, Japan
| | | | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen, Germany.
| |
Collapse
|
7
|
Balaraman V, Indran SV, Li Y, Meekins DA, Jakkula LU, Liu H, Hays MP, Souza-Neto JA, Gaudreault NN, Hardwidge PR, Wilson WC, Weber F, Richt JA. Identification of host factors for Rift Valley Fever Phlebovirus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.28.559935. [PMID: 37808812 PMCID: PMC10557628 DOI: 10.1101/2023.09.28.559935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Background Rift Valley fever phlebovirus (RVFV) is a zoonotic pathogen that causes Rift Valley fever (RVF) in livestock and humans. Currently, there is no licensed human vaccine or antiviral drug to control RVF. Although multiple species of animals and humans are vulnerable to RVFV infection, host factors affecting susceptibility are not well understood. Methodology To identify the host factors or genes essential for RVFV replication, we conducted a CRISPR-Cas9 knock-out screen in human A549 cells. We then validated the putative genes using siRNA-mediated knockdowns and CRISPR-Cas9-mediated knockout studies, respectively. The role of a candidate gene in the virus replication cycle was assessed by measuring intracellular viral RNA accumulation, and the virus titers by plaque assay or TCID50 assay. Findings We identified approximately 900 genes with potential involvement in RVFV infection and replication. Further evaluation of the effect of six genes on viral replication using siRNA-mediated knockdowns found that silencing two genes (WDR7 and LRP1) significantly impaired RVFV replication. For further analysis, we focused on the WDR7 gene since the role of LRP1 in RVFV replication was previously described in detail. Knock-out A549 cell lines were generated and used to dissect the effect of WRD7 on RVFV and another bunyavirus, La Crosse encephalitis virus (LACV). We observed significant effects of WDR7 knock-out cells on both intracellular RVFV RNA levels and viral titers. At the intracellular RNA level, WRD7 affected RVFV replication at a later phase of its replication cycle (24h) when compared to LACV which was affected an earlier replication phase (12h). Conclusion In summary, we have identified WDR7 as an essential host factor for the replication of two relevant bunyaviruses, RVFV and LACV. Future studies will investigate the mechanistic role by which WDR7 facilitates Phlebovirus replication.
Collapse
Affiliation(s)
- Velmurugan Balaraman
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Sabarish V. Indran
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Yonghai Li
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - David A. Meekins
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Laxmi U.M.R. Jakkula
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Heidi Liu
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Micheal P. Hays
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Jayme A. Souza-Neto
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Natasha N. Gaudreault
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Philip R. Hardwidge
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - William C. Wilson
- United States Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Foreign Arthropod-Borne Animal Diseases Research Unit, Manhattan, Kansas, United States of America
| | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen, Germany
| | - Juergen A. Richt
- Center of Excellence for Emerging and Zoonotic Animal Diseases and Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| |
Collapse
|
8
|
Devignot S, Sha TW, Burkard TR, Schmerer P, Hagelkruys A, Mirazimi A, Elling U, Penninger JM, Weber F. Low-density lipoprotein receptor-related protein 1 (LRP1) as an auxiliary host factor for RNA viruses. Life Sci Alliance 2023; 6:e202302005. [PMID: 37072184 PMCID: PMC10114362 DOI: 10.26508/lsa.202302005] [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: 02/22/2023] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/20/2023] Open
Abstract
Viruses with an RNA genome are often the cause of zoonotic infections. In order to identify novel pro-viral host cell factors, we screened a haploid insertion-mutagenized mouse embryonic cell library for clones that are resistant to Rift Valley fever virus (RVFV). This screen returned the low-density lipoprotein receptor-related protein 1 (LRP1) as a top hit, a plasma membrane protein involved in a wide variety of cell activities. Inactivation of LRP1 in human cells reduced RVFV RNA levels already at the attachment and entry stages of infection. Moreover, the role of LRP1 in promoting RVFV infection was dependent on physiological levels of cholesterol and on endocytosis. In the human cell line HuH-7, LRP1 also promoted early infection stages of sandfly fever Sicilian virus and La Crosse virus, but had a minor effect on late infection by vesicular stomatitis virus, whereas encephalomyocarditis virus was entirely LRP1-independent. Moreover, siRNA experiments in human Calu-3 cells demonstrated that also SARS-CoV-2 infection benefitted from LRP1. Thus, we identified LRP1 as a host factor that supports infection by a spectrum of RNA viruses.
Collapse
Affiliation(s)
- Stephanie Devignot
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen, Germany
| | - Tim Wai Sha
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen, Germany
| | - Thomas R Burkard
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - Patrick Schmerer
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen, Germany
| | - Astrid Hagelkruys
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - Ali Mirazimi
- Public Health Agency of Sweden, Solna, Sweden
- Department of Laboratory Medicine, Karolinska Institutet, Solna, Sweden
| | - Ulrich Elling
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - Josef M Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen, Germany
- German Centre for Infection Research (DZIF), Partner Site Giessen, Giessen, Germany
| |
Collapse
|
9
|
Bermúdez-Méndez E, Angelino P, van Keulen L, van de Water S, Rockx B, Pijlman GP, Ciuffi A, Kortekaas J, Wichgers Schreur PJ. Transcriptomic Profiling Reveals Intense Host-Pathogen Dispute Compromising Homeostasis during Acute Rift Valley Fever Virus Infection. J Virol 2023; 97:e0041523. [PMID: 37306574 PMCID: PMC10308945 DOI: 10.1128/jvi.00415-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 05/13/2023] [Indexed: 06/13/2023] Open
Abstract
Rift Valley fever virus (RVFV) (family Phenuiviridae) can cause severe disease, and outbreaks of this mosquito-borne pathogen pose a significant threat to public and animal health. Yet many molecular aspects of RVFV pathogenesis remain incompletely understood. Natural RVFV infections are acute, characterized by a rapid onset of peak viremia during the first days post-infection, followed by a rapid decline. Although in vitro studies identified a major role of interferon (IFN) responses in counteracting the infection, a comprehensive overview of the specific host factors that play a role in RVFV pathogenesis in vivo is still lacking. Here, the host in vivo transcriptional profiles in the liver and spleen tissues of lambs exposed to RVFV are studied using RNA sequencing (RNA-seq) technology. We validate that IFN-mediated pathways are robustly activated in response to infection. We also link the observed hepatocellular necrosis with severely compromised organ function, which is reflected as a marked downregulation of multiple metabolic enzymes essential for homeostasis. Furthermore, we associate the elevated basal expression of LRP1 in the liver with RVFV tissue tropism. Collectively, the results of this study deepen the knowledge of the in vivo host response during RVFV infection and reveal new insights into the gene regulation networks underlying pathogenesis in a natural host. IMPORTANCE Rift Valley fever virus (RVFV) is a mosquito-transmitted pathogen capable of causing severe disease in animals and humans. Outbreaks of RVFV pose a significant threat to public health and can result in substantial economic losses. Little is known about the molecular basis of RVFV pathogenesis in vivo, particularly in its natural hosts. We employed RNA-seq technology to investigate genome-wide host responses in the liver and spleen of lambs during acute RVFV infection. We show that RVFV infection drastically decreases the expression of metabolic enzymes, which impairs normal liver function. Moreover, we highlight that basal expression levels of the host factor LRP1 may be a determinant of RVFV tissue tropism. This study links the typical pathological phenotype induced by RVFV infection with tissue-specific gene expression profiles, thereby improving our understanding of RVFV pathogenesis.
Collapse
Affiliation(s)
- Erick Bermúdez-Méndez
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
- Laboratory of Virology, Wageningen University & Research, Wageningen, The Netherlands
- Institute of Microbiology, Lausanne University Hospital, Lausanne, Switzerland
- Institute of Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Paolo Angelino
- Institute of Microbiology, Lausanne University Hospital, Lausanne, Switzerland
- Institute of Microbiology, University of Lausanne, Lausanne, Switzerland
- Bioinformatics Core Facility, Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Lucien van Keulen
- Department of Bacteriology, Host-Pathogen Interaction and Diagnostics Development, Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Sandra van de Water
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Barry Rockx
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Gorben P. Pijlman
- Laboratory of Virology, Wageningen University & Research, Wageningen, The Netherlands
| | - Angela Ciuffi
- Institute of Microbiology, Lausanne University Hospital, Lausanne, Switzerland
- Institute of Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Jeroen Kortekaas
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
- Laboratory of Virology, Wageningen University & Research, Wageningen, The Netherlands
| | - Paul J. Wichgers Schreur
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
| |
Collapse
|
10
|
Godbold GD, Hewitt FC, Kappell AD, Scholz MB, Agar SL, Treangen TJ, Ternus KL, Sandbrink JB, Koblentz GD. Improved understanding of biorisk for research involving microbial modification using annotated sequences of concern. Front Bioeng Biotechnol 2023; 11:1124100. [PMID: 37180048 PMCID: PMC10167326 DOI: 10.3389/fbioe.2023.1124100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 04/11/2023] [Indexed: 05/15/2023] Open
Abstract
Regulation of research on microbes that cause disease in humans has historically been focused on taxonomic lists of 'bad bugs'. However, given our increased knowledge of these pathogens through inexpensive genome sequencing, 5 decades of research in microbial pathogenesis, and the burgeoning capacity of synthetic biologists, the limitations of this approach are apparent. With heightened scientific and public attention focused on biosafety and biosecurity, and an ongoing review by US authorities of dual-use research oversight, this article proposes the incorporation of sequences of concern (SoCs) into the biorisk management regime governing genetic engineering of pathogens. SoCs enable pathogenesis in all microbes infecting hosts that are 'of concern' to human civilization. Here we review the functions of SoCs (FunSoCs) and discuss how they might bring clarity to potentially problematic research outcomes involving infectious agents. We believe that annotation of SoCs with FunSoCs has the potential to improve the likelihood that dual use research of concern is recognized by both scientists and regulators before it occurs.
Collapse
Affiliation(s)
| | | | | | | | - Stacy L. Agar
- Signature Science, LLC, Charlottesville, VA, United States
| | - Todd J. Treangen
- Department of Computer Science, Rice University, Houston, TX, United States
| | | | - Jonas B. Sandbrink
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Gregory D. Koblentz
- Schar School of Policy and Government, George Mason University, Arlington, VA, United States
| |
Collapse
|
11
|
Wang X, Yuan Y, Liu Y, Zhang L. Arm race between Rift Valley fever virus and host. Front Immunol 2022; 13:1084230. [PMID: 36618346 PMCID: PMC9813963 DOI: 10.3389/fimmu.2022.1084230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
Rift Valley fever (RVF) is a zoonotic disease caused by Rift Valley fever virus (RVFV), an emerging arbovirus within the Phenuiviridae family of Bunyavirales that has potential to cause severe diseases in both humans and livestock. It increases the incidence of abortion or foetal malformation in ruminants and leads to clinical manifestations like encephalitis or haemorrhagic fever in humans. Upon virus invasion, the innate immune system from the cell or the organism is activated to produce interferon (IFN) and prevent virus proliferation. Meanwhile, RVFV initiates countermeasures to limit antiviral responses at transcriptional and protein levels. RVFV nonstructural proteins (NSs) are the key virulent factors that not only perform immune evasion but also impact the cell replication cycle and has cytopathic effects. In this review, we summarize the innate immunity host cells employ depending on IFN signal transduction pathways, as well as the immune evasion mechanisms developed by RVFV primarily with the inhibitory activity of NSs protein. Clarifying the arms race between host innate immunity and RVFV immune evasion provides new avenues for drug target screening and offers possible solutions to current and future epidemics.
Collapse
Affiliation(s)
- Xiao Wang
- Department of Infectious Diseases, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China,Department of Pathogen Biology, School of Clinical and Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Yupei Yuan
- Department of Pathogen Biology, School of Clinical and Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Yihan Liu
- Department of Pathogen Biology, School of Clinical and Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Leiliang Zhang
- Department of Infectious Diseases, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China,Department of Pathogen Biology, School of Clinical and Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China,*Correspondence: Leiliang Zhang,
| |
Collapse
|
12
|
Wuerth JD, Weber F. Shielding the mRNA-translation factor eIF2B from inhibitory p-eIF2 as a viral strategy to evade protein kinase R-mediated innate immunity. Curr Opin Immunol 2022; 78:102251. [PMID: 36242870 DOI: 10.1016/j.coi.2022.102251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 09/05/2022] [Indexed: 01/29/2023]
Abstract
The interferon-regulated kinase PKR (protein kinase RNA-activated) is a potent innate immune factor against a broad range of viruses. Being part of the integrated stress response (ISR), its restrictive effect is predominantly exerted by phosphorylating the eukaryotic translation-initiation factor eIF2, thereby turning it into an inhibitor of translation-initiation factor eIF2B. A plethora of viruses are known to evade the shutdown of cellular mRNA translation by interfering either with PKR activation or with eIF2 phosphorylation. Recently, a novel PKR evasion strategy was described: proteins from three taxonomically distinct RNA viruses allow for full PKR activation and eIF2 phosphorylation in the infected cell, but protect eIF2B from inhibition by phosphorylated eIF2, thus enabling mRNA translation in the presence of an activated ISR.
Collapse
Affiliation(s)
- Jennifer D Wuerth
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, Germany
| | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, D-35392 Giessen, Germany.
| |
Collapse
|
13
|
Boshra H. An Overview of the Infectious Cycle of Bunyaviruses. Viruses 2022; 14:v14102139. [PMID: 36298693 PMCID: PMC9610998 DOI: 10.3390/v14102139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/19/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022] Open
Abstract
Bunyaviruses represent the largest group of RNA viruses and are the causative agent of a variety of febrile and hemorrhagic illnesses. Originally characterized as a single serotype in Africa, the number of described bunyaviruses now exceeds over 500, with its presence detected around the world. These predominantly tri-segmented, single-stranded RNA viruses are transmitted primarily through arthropod and rodent vectors and can infect a wide variety of animals and plants. Although encoding for a small number of proteins, these viruses can inflict potentially fatal disease outcomes and have even developed strategies to suppress the innate antiviral immune mechanisms of the infected host. This short review will attempt to provide an overall description of the order Bunyavirales, describing the mechanisms behind their infection, replication, and their evasion of the host immune response. Furthermore, the historical context of these viruses will be presented, starting from their original discovery almost 80 years ago to the most recent research pertaining to viral replication and host immune response.
Collapse
Affiliation(s)
- Hani Boshra
- Global Urgent and Advanced Research and Development (GUARD), 911 Rue Principale, Batiscan, QC G0X 1A0, Canada
| |
Collapse
|
14
|
Hufsky F, Beslic D, Boeckaerts D, Duchene S, González-Tortuero E, Gruber AJ, Guo J, Jansen D, Juma J, Kongkitimanon K, Luque A, Ritsch M, Lencioni Lovate G, Nishimura L, Pas C, Domingo E, Hodcroft E, Lemey P, Sullivan MB, Weber F, González-Candelas F, Krautwurst S, Pérez-Cataluña A, Randazzo W, Sánchez G, Marz M. The International Virus Bioinformatics Meeting 2022. Viruses 2022; 14:973. [PMID: 35632715 PMCID: PMC9144528 DOI: 10.3390/v14050973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 12/22/2022] Open
Abstract
The International Virus Bioinformatics Meeting 2022 took place online, on 23-25 March 2022, and has attracted about 380 participants from all over the world. The goal of the meeting was to provide a meaningful and interactive scientific environment to promote discussion and collaboration and to inspire and suggest new research directions and questions. The participants created a highly interactive scientific environment even without physical face-to-face interactions. This meeting is a focal point to gain an insight into the state-of-the-art of the virus bioinformatics research landscape and to interact with researchers in the forefront as well as aspiring young scientists. The meeting featured eight invited and 18 contributed talks in eight sessions on three days, as well as 52 posters, which were presented during three virtual poster sessions. The main topics were: SARS-CoV-2, viral emergence and surveillance, virus-host interactions, viral sequence analysis, virus identification and annotation, phages, and viral diversity. This report summarizes the main research findings and highlights presented at the meeting.
Collapse
Affiliation(s)
- Franziska Hufsky
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- RNA Bioinformatics and High-Throughput Analysis, Friedrich Schiller University Jena, 07743 Jena, Germany;
| | - Denis Beslic
- Methodology and Research Infrastructure, MF1 Bioinformatics, Robert Koch Institute, 13353 Berlin, Germany;
| | - Dimitri Boeckaerts
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, 9000 Ghent, Belgium; (D.B.); (C.P.)
- KERMIT, Department of Data Analysis and Mathematical Modelling, Ghent University, 9000 Ghent, Belgium
| | - Sebastian Duchene
- Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne 3000, Australia;
| | - Enrique González-Tortuero
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- School of Science, Engineering and Environment (SEE), University of Salford, Salford M5 4WT, UK
| | - Andreas J. Gruber
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Department of Biology, University of Konstanz, 78464 Konstanz, Germany
| | - Jiarong Guo
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Departments of Microbiology, and Civil, Environmental, and Geodetic Engineering, Ohio State University, Columbus, OH 43210, USA
| | - Daan Jansen
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Viral Metagenomics, KU Leuven, 3000 Leuven, Belgium
| | - John Juma
- International Livestock Research Institute (ILRI), Nairobi 00100, Kenya;
- South African National Bioinformatics Institute, South African MRC Bioinformatics Unit, Cape Town 7530, South Africa
| | - Kunaphas Kongkitimanon
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Methodology and Research Infrastructure, MF1 Bioinformatics, Robert Koch Institute, 13353 Berlin, Germany;
| | - Antoni Luque
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Viral Information Institute, San Diego State University, San Diego, CA 92116, USA
- Computational Science Research Center, San Diego State University, San Diego, CA 92116, USA
- Department of Mathematics and Statistics, San Diego State University, San Diego, CA 92116, USA
| | - Muriel Ritsch
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- RNA Bioinformatics and High-Throughput Analysis, Friedrich Schiller University Jena, 07743 Jena, Germany;
| | - Gabriel Lencioni Lovate
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- RNA Bioinformatics and High-Throughput Analysis, Friedrich Schiller University Jena, 07743 Jena, Germany;
- JRG Analytical MicroBioinformatics, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Luca Nishimura
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Mishima 411-8540, Japan
- Human Genetics Laboratory, National Institute of Genetics, Mishima 411-8540, Japan
| | - Célia Pas
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, 9000 Ghent, Belgium; (D.B.); (C.P.)
| | - Esteban Domingo
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) del Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Emma Hodcroft
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Institute of Social and Preventive Medicine, University of Bern, 3012 Bern, Switzerland
- Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Philippe Lemey
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, 3000 Leuven, Belgium
| | - Matthew B. Sullivan
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Departments of Microbiology, and Civil, Environmental, and Geodetic Engineering, Ohio State University, Columbus, OH 43210, USA
| | - Friedemann Weber
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Institute for Virology, Veterinary Medicine, Justus-Liebig University, 35390 Gießen, Germany
| | - Fernando González-Candelas
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- Joint Research Unit “Infection and Public Health” FISABIO, University of Valencia, 46010 Valencia, Spain
- Institute for Integrative Systems Biology (I2SysBio), CSIC, University of Valencia, 46010 Valencia, Spain
| | - Sarah Krautwurst
- RNA Bioinformatics and High-Throughput Analysis, Friedrich Schiller University Jena, 07743 Jena, Germany;
| | - Alba Pérez-Cataluña
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- VISAFELab, Department of Preservation and Food Safety Technologies, Institute of Agrochemistry and Food Technology, IATA-CSIC, 46980 Valencia, Spain
| | - Walter Randazzo
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- VISAFELab, Department of Preservation and Food Safety Technologies, Institute of Agrochemistry and Food Technology, IATA-CSIC, 46980 Valencia, Spain
| | - Gloria Sánchez
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- VISAFELab, Department of Preservation and Food Safety Technologies, Institute of Agrochemistry and Food Technology, IATA-CSIC, 46980 Valencia, Spain
| | - Manja Marz
- European Virus Bioinformatics Center, 07743 Jena, Germany; (E.G.-T.); (A.J.G.); (J.G.); (D.J.); (K.K.); (A.L.); (M.R.); (G.L.L.); (L.N.); (E.D.); (E.H.); (P.L.); (M.B.S.); (F.W.); (F.G.-C.); (A.P.-C.); (W.R.); (G.S.)
- RNA Bioinformatics and High-Throughput Analysis, Friedrich Schiller University Jena, 07743 Jena, Germany;
| |
Collapse
|
15
|
Song H, Tian D, Sun J, Mao X, Kong W, Xu D, Ji Y, Qiu B, Zhan M, Wang J. circFAM120B functions as a tumor suppressor in esophageal squamous cell carcinoma via the miR-661/PPM1L axis and the PKR/p38 MAPK/EMT pathway. Cell Death Dis 2022; 13:361. [PMID: 35436983 PMCID: PMC9016076 DOI: 10.1038/s41419-022-04818-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 03/18/2022] [Accepted: 03/31/2022] [Indexed: 02/07/2023]
Abstract
Extensive changes of circRNA expression underscore their essential contributions to multiple hallmarks of cancers; however, their functions and mechanisms of action in esophageal squamous cell carcinoma (ESCC) remain undetermined. Here, we adopted a three-stage approach by first screening for significantly differentially expressed circRNAs in ESCC and performing an external validation study, followed by the functional analyses. The properties of circRNAs were evaluated using Sanger sequencing, RNase R digestion, actinomycin D treatment, subcellular localization analysis, and fluorescence in situ hybridization. Target transcripts were predicted using online tools and verified by dual-luciferase, RNA immunoprecipitation, qRT-PCR, and western blot. Biotin-labeled RNA-protein pull-down, mass spectrometry, and RNA immunoprecipitation were employed to identify proteins interacting with circRNAs. Gain- and loss-of-function experiments were performed to uncover the roles of circRNAs, their target genes, and binding proteins in the proliferation, metastasis, and invasion. We observed that circFAM120B (hsa_circ_0001666) was frequently downregulated in cancer tissues and patient plasma, and its expression level was related to overall survival in ESCC patients. Overexpression of circFAM120B inhibited the proliferation, metastasis, and invasion of ESCC while silencing it enhanced malignant phenotypes. Mechanistically, circFAM120B was predominantly located in the cytoplasm, guarantying its sponging for miR-661 to restore the expression of PPM1L, a tumor suppressor. We observed that circFAM120B could reduce the stability of RNA-dependent protein kinase (PKR) by promoting its ubiquitination-dependent degradation and subsequently regulating the p38 MAPK signaling pathway, resulting in the repression of EMTs in ESCC cells. Our findings suggest that circFAM120B is a promising biomarker of ESCC, which acts as a tumor suppressor via the circFAM120B/miR-661/PPM1L axis and PKR/p38 MAPK/EMT pathway, supporting its significance as a candidate therapeutic target.
Collapse
Affiliation(s)
- Huan Song
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China
| | - Dan Tian
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China
| | - Jian Sun
- Department of Thoracic Surgery, The First People's Hospital of Yancheng and Yancheng Clinical College of Xuzhou Medical University, Yancheng, 224001, China
| | - Xuhua Mao
- Department of Clinical Laboratory, Yixing People's Hospital, Wuxi, 214200, China
| | - Weimin Kong
- Department of Thoracic Surgery, The First People's Hospital of Yancheng and Yancheng Clinical College of Xuzhou Medical University, Yancheng, 224001, China
| | - Dian Xu
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China
| | - Ye Ji
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China
| | - Beibei Qiu
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China
| | - Mengyao Zhan
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China
| | - Jianming Wang
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China. .,Department of Epidemiology, Gusu School, Nanjing Medical University, Nanjing, 211166, China.
| |
Collapse
|
16
|
Kashiwagi K, Shichino Y, Osaki T, Sakamoto A, Nishimoto M, Takahashi M, Mito M, Weber F, Ikeuchi Y, Iwasaki S, Ito T. eIF2B-capturing viral protein NSs suppresses the integrated stress response. Nat Commun 2021; 12:7102. [PMID: 34876589 PMCID: PMC8651795 DOI: 10.1038/s41467-021-27337-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 11/14/2021] [Indexed: 12/17/2022] Open
Abstract
Various stressors such as viral infection lead to the suppression of cap-dependent translation and the activation of the integrated stress response (ISR), since the stress-induced phosphorylated eukaryotic translation initiation factor 2 [eIF2(αP)] tightly binds to eIF2B to prevent it from exchanging guanine nucleotide molecules on its substrate, unphosphorylated eIF2. Sandfly fever Sicilian virus (SFSV) evades this cap-dependent translation suppression through the interaction between its nonstructural protein NSs and host eIF2B. However, its precise mechanism has remained unclear. Here, our cryo-electron microscopy (cryo-EM) analysis reveals that SFSV NSs binds to the α-subunit of eIF2B in a competitive manner with eIF2(αP). Together with SFSV NSs, eIF2B retains nucleotide exchange activity even in the presence of eIF2(αP), in line with the cryo-EM structures of the eIF2B•SFSV NSs•unphosphorylated eIF2 complex. A genome-wide ribosome profiling analysis clarified that SFSV NSs expressed in cultured human cells attenuates the ISR triggered by thapsigargin, an endoplasmic reticulum stress inducer. Furthermore, SFSV NSs introduced in rat hippocampal neurons and human induced-pluripotent stem (iPS) cell-derived motor neurons exhibits neuroprotective effects against the ISR-inducing stress. Since ISR inhibition is beneficial in various neurological disease models, SFSV NSs may be a promising therapeutic ISR inhibitor.
Collapse
Affiliation(s)
- Kazuhiro Kashiwagi
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Yuichi Shichino
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, 351-0198, Japan
| | - Tatsuya Osaki
- Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo, 153-8505, Japan
| | - Ayako Sakamoto
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Madoka Nishimoto
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Mari Takahashi
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Mari Mito
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, 351-0198, Japan
| | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen, D-35392, Germany
| | - Yoshiho Ikeuchi
- Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo, 153-8505, Japan.
- Institute for AI and Beyond, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8655, Japan.
| | - Shintaro Iwasaki
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, 351-0198, Japan.
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8561, Japan.
| | - Takuhiro Ito
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama, 230-0045, Japan.
| |
Collapse
|
17
|
Wu A, Lin L, Li X, Xu Q, Xu W, Zhu X, Teng Y, Yang X, Ai Z. Overexpression of ARHGAP30 suppresses growth of cervical cancer cells by downregulating ribosome biogenesis. Cancer Sci 2021; 112:4515-4525. [PMID: 34490691 PMCID: PMC8586670 DOI: 10.1111/cas.15130] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 08/25/2021] [Accepted: 09/01/2021] [Indexed: 01/02/2023] Open
Abstract
We aimed to identify whether Rho GTPase activating proteins (RhoGAPs) were downregulated in cervical cancers and might be targeted to reduce the growth of cervical cancer using the GEO database and immunohistochemical analysis to identified changes in transcription and protein levels. We analyzed their proliferation, clone formation ability, and their growth as subcutaneous tumors in mice. To detect ARHGAP30 localization in cells, immunofluorescence assays were conducted. Mass spectrometry combined with immunoprecipitation experiments were used to identify binding proteins. Protein interactions were validated with co-immunoprecipitation assays. Western-blot and q-PCR were applied to analyze candidate binding proteins that were associated with ribosome biogenesis. Puromycin incorporation assay was used to detect the global protein synthesis rate. We identified that ARHGAP30 was the only downregulated RhoGAP and was related to the survival of cervical cancer patients. Overexpression of ARHGAP30 in cervical cancer cells inhibited cell proliferation and migration. ARHGAP30 immunoprecipitated proteins were enriched in the ribosome biogenesis process. ARHGAP30 was located in the nucleous and interacted with nucleolin (NCL). Overexpression of ARHGAP30 inhibited rRNA synthesis and global protein synthesis. ARHGAP30 overexpression induced the ubiquitination of NCL and decreased its protein level in Hela cells. The function of ARHGAP30 on cervical cancer cell ribosome biogenesis and proliferation was independent of its RhoGAP activity as assessed with a RhoGAP-deficient plasmid of ARHGAP30R55A . Overall, the findings revealed that ARHGAP30 was frequently downregulated and associated with shorter survival of cervical cancer patients. ARHGAP30 may suppress growth of cervical cancer by reducing ribosome biogenesis and protein synthesis through promoting ubiquitination of NCL.
Collapse
Affiliation(s)
- Aijia Wu
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Lan Lin
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Xiao Li
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Qinyang Xu
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Wei Xu
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Xiaolu Zhu
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Yincheng Teng
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Xiao‐Mei Yang
- State Key Laboratory of Oncogenes and Related GenesShanghai Cancer InstituteRen Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina
| | - Zhihong Ai
- Department of Obstetrics and GynecologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| |
Collapse
|
18
|
Peng K, Lozach PY. Rift Valley fever virus: a new avenue of research on the biological functions of amyloids? Future Virol 2021. [DOI: 10.2217/fvl-2021-0094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rift Valley fever is a mosquito-borne viral zoonosis that was first discovered in the Great Rift Valley, Kenya, in 1930. Rift Valley fever virus (RVFV) primarily infects domestic animals and humans, with clinical outcomes ranging from self-limiting febrile illness to acute hepatitis and encephalitis. The virus left Africa a few decades ago, and there is a risk of introduction into southern Europe and Asia. From this perspective, we introduce RVFV and focus on the capacity of its virulence factor, the nonstructural protein NSs, to form amyloid-like fibrils. Here, we discuss the implications for the NSs biological function, the ability of RVFV to evade innate immunity, and RVFV virulence and neurotoxicity.
Collapse
Affiliation(s)
- Ke Peng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei, 430071, PR China
- University of the Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Pierre-Yves Lozach
- Cell Networks, CIID (Cluster of Excellence & Center for Integrative Infectious Disease Research), Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany
- University of Lyon, INRAE, EPHE, IVPC (Infections Virales et Pathologie Comparée), 69007, Lyon, France
| |
Collapse
|
19
|
Host Cell Restriction Factors of Bunyaviruses and Viral Countermeasures. Viruses 2021; 13:v13050784. [PMID: 33925004 PMCID: PMC8146327 DOI: 10.3390/v13050784] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/14/2021] [Accepted: 04/20/2021] [Indexed: 01/01/2023] Open
Abstract
The Bunyavirales order comprises more than 500 viruses (generally defined as bunyaviruses) classified into 12 families. Some of these are highly pathogenic viruses infecting different hosts, including humans, mammals, reptiles, arthropods, birds, and/or plants. Host cell sensing of infection activates the innate immune system that aims at inhibiting viral replication and propagation. Upon recognition of pathogen-associated molecular patterns (PAMPs) by cellular pattern recognition receptors (PRRs), numerous signaling cascades are activated, leading to the production of interferons (IFNs). IFNs act in an autocrine and paracrine manner to establish an antiviral state by inducing the expression of hundreds of IFN-stimulated genes (ISGs). Some of these ISGs are known to restrict bunyavirus infection. Along with other constitutively expressed host cellular factors with antiviral activity, these proteins (hereafter referred to as “restriction factors”) target different steps of the viral cycle, including viral entry, genome transcription and replication, and virion egress. In reaction to this, bunyaviruses have developed strategies to circumvent this antiviral response, by avoiding cellular recognition of PAMPs, inhibiting IFN production or interfering with the IFN-mediated response. Herein, we review the current knowledge on host cellular factors that were shown to restrict infections by bunyaviruses. Moreover, we focus on the strategies developed by bunyaviruses in order to escape the antiviral state developed by the infected cells.
Collapse
|
20
|
Rosche KL, Sidak-Loftis LC, Hurtado J, Fisk EA, Shaw DK. Arthropods Under Pressure: Stress Responses and Immunity at the Pathogen-Vector Interface. Front Immunol 2021; 11:629777. [PMID: 33659000 PMCID: PMC7917218 DOI: 10.3389/fimmu.2020.629777] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 12/30/2020] [Indexed: 12/14/2022] Open
Abstract
Understanding what influences the ability of some arthropods to harbor and transmit pathogens may be key for controlling the spread of vector-borne diseases. Arthropod immunity has a central role in dictating vector competence for pathogen acquisition and transmission. Microbial infection elicits immune responses and imparts stress on the host by causing physical damage and nutrient deprivation, which triggers evolutionarily conserved stress response pathways aimed at restoring cellular homeostasis. Recent studies increasingly recognize that eukaryotic stress responses and innate immunity are closely intertwined. Herein, we describe two well-characterized and evolutionarily conserved mechanisms, the Unfolded Protein Response (UPR) and the Integrated Stress Response (ISR), and examine evidence that these stress responses impact immune signaling. We then describe how multiple pathogens, including vector-borne microbes, interface with stress responses in mammals. Owing to the well-conserved nature of the UPR and ISR, we speculate that similar mechanisms may be occurring in arthropod vectors and ultimately impacting vector competence. We conclude this Perspective by positing that novel insights into vector competence will emerge when considering that stress-signaling pathways may be influencing the arthropod immune network.
Collapse
Affiliation(s)
- Kristin L Rosche
- Program in Vector-borne Disease, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
| | - Lindsay C Sidak-Loftis
- Program in Vector-borne Disease, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
| | - Joanna Hurtado
- Program in Vector-borne Disease, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
| | - Elizabeth A Fisk
- Program in Vector-borne Disease, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
| | - Dana K Shaw
- Program in Vector-borne Disease, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
| |
Collapse
|
21
|
Abstract
Rift Valley fever (RVF) is a zoonotic, vector-borne infectious disease of ruminants and camels transmitted mainly by the Aedes and Culex mosquito species. Contact with the blood or organs of infected animals may infect humans. Its etiological factor is the Rift Valley fever virus (RVFV) of the Phlebovirus genus and Bunyaviridae family. Sheep and goats are most susceptible to infection and newborns and young individuals endure the most severe disease course. High abortion rates and infant mortality are typical for RVF; its clinical signs are high fever, lymphadenitis, nasal and ocular secretions and vomiting. Conventional diagnosis is done by the detection of specific IgM or IgG antibodies and RVFV nucleic acids and by virus isolation. Inactivated and live-attenuated vaccines obtained from virulent RVFV isolates are available for livestock. RVF is endemic in sub-Saharan Africa and the Arabian Peninsula, but in the last two decades, it was also reported in other African regions. Seropositive animals were detected in Turkey, Tunisia and Libya. The wide distribution of competent vectors in non-endemic areas coupled with global climate change threaten to spread RVF transboundarily. The EFSA considers the movement of infected animals and vectors to be other plausible pathways of RVF introduction into Europe. A very low risk both of introduction of the virus through an infected animal or vector and of establishment of the virus, and a moderate risk of its transmission through these means was estimated for Poland. The risk of these specific modes of disease introduction into Europe is rated as very low, but surveillance and response capabilities and cooperation with the proximal endemic regions are recommended.
Collapse
|
22
|
Ding J, Zhao J, Huan L, Liu Y, Qiao Y, Wang Z, Chen Z, Huang S, Zhao Y, He X. Inflammation-Induced Long Intergenic Noncoding RNA (LINC00665) Increases Malignancy Through Activating the Double-Stranded RNA-Activated Protein Kinase/Nuclear Factor Kappa B Pathway in Hepatocellular Carcinoma. Hepatology 2020; 72:1666-1681. [PMID: 32083756 DOI: 10.1002/hep.31195] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 01/09/2020] [Accepted: 01/26/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND AIMS The nuclear factor kappa B (NF-κB) signaling pathway is important for linking inflammation and tumorigenesis. Here, we characterized an NF-κB signaling activation-induced long intergenic noncoding (LINC) RNA in hepatocellular carcinoma (HCC), LINC00665, that contributes to the enhanced cell proliferation of HCC cells both in vitro and in vivo. APPROACH AND RESULTS LINC00665 physically interacts with the double-stranded RNA (dsRNA)-activated protein kinase (PKR), enhances its activation, and maintains its protein stability by blocking ubiquitin/proteasome-dependent degradation, resulting in a positive feedback regulation of NF-κB signaling in HCC cells. Notably, patients with HCC and higher LINC00665 have poorer outcomes in the clinic. CONCLUSIONS Our findings indicate that LINC00665 is involved in the NF-κB signaling activation in HCC cells and that the inflammatory LINC00665/PKR/NF-κB loop plays important oncogenic roles in hepatic cancer progression and may be a potential therapeutic target.
Collapse
Affiliation(s)
- Jie Ding
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jingjing Zhao
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Lin Huan
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yizhe Liu
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yejun Qiao
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhen Wang
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhiao Chen
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Shenglin Huang
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China
| | - Yingjun Zhao
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China
| | - Xianghuo He
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China
| |
Collapse
|
23
|
Gori Savellini G, Bini L, Gagliardi A, Anichini G, Gandolfo C, Prathyumnan S, Cusi MG. Ubiquitin and Not Only Unfolded Domains Drives Toscana Virus Non-Structural NSs Protein Degradation. Viruses 2020; 12:E1153. [PMID: 33053780 PMCID: PMC7601456 DOI: 10.3390/v12101153] [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: 09/11/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 01/09/2023] Open
Abstract
The non-structural protein NSs of the Phenuiviridae family members appears to have a role in the host immunity escape. The stability of Toscana virus (TOSV) NSs protein was tested by a cycloheximide (CHX) chase approach on cells transfected with NSs deleted versions fused to a reporter gene. The presence of intrinsically disordered regions (IDRs) both at the C- and N-terminus appeared to affect the protein stability. Indeed, the NSsΔC and NSsΔN proteins were more stable than the wild-type NSs counterpart. Since TOSV NSs exerts its inhibitory function by triggering RIG-I for proteasomal degradation, the interaction of the ubiquitin system and TOSV NSs was further examined. Chase experiments with CHX and the proteasome inhibitor MG-132 demonstrated the involvement of the ubiquitin-proteasome system in controlling NSs protein amount expressed in the cells. The analysis of TOSV NSs by mass spectrometry allowed the direct identification of K104, K109, K154, K180, K244, K294, and K298 residues targeted for ubiquitination. Analysis of NSs K-mutants confirmed the presence and the important role of lysine residues located in the central and the C-terminal parts of the protein in controlling the NSs cellular level. Therefore, we directly demonstrated a new cellular pathway involved in controlling TOSV NSs fate and activity, and this opens the way to new investigations among more pathogenic viruses of the Phenuiviridae family.
Collapse
Affiliation(s)
- Gianni Gori Savellini
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
| | - Luca Bini
- Department of Life Sciences, University of Siena, 53100 Siena, Italy;
| | - Assunta Gagliardi
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Laboratory of Synthetic and Structural Vaccinology, 38122 Trento, Italy;
| | - Gabriele Anichini
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
| | - Claudia Gandolfo
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
- S. Maria delle Scotte Hospital, V.le Bracci, 1, 53100 Siena, Italy
| | - Shibily Prathyumnan
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
| | - Maria Grazia Cusi
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
- S. Maria delle Scotte Hospital, V.le Bracci, 1, 53100 Siena, Italy
| |
Collapse
|
24
|
Ren F, Zhou M, Deng F, Wang H, Ning YJ. Combinatorial Minigenome Systems for Emerging Banyangviruses Reveal Viral Reassortment Potential and Importance of a Protruding Nucleotide in Genome "Panhandle" for Promoter Activity and Reassortment. Front Microbiol 2020; 11:599. [PMID: 32322247 PMCID: PMC7156889 DOI: 10.3389/fmicb.2020.00599] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/18/2020] [Indexed: 12/25/2022] Open
Abstract
Banyangvirus is a new genus (Phenuiviridae family, Bunyavirales order) that comprises a group of emerging tick-borne viruses with severe fever with thrombocytopenia syndrome virus (SFTSV) and Heartland virus (HRTV) as virulent representatives. As segmented RNA viruses, bunyaviruses may have genome reassortment potential, increasing the concern about new life-threatening bunyavirus emergence. Using a series of combinatory minigenome reporter assays based on transfection and superinfection, we showed that replication machinery proteins of designated banyangviruses can recognize genomic untranslated regions (UTRs) of other banyangviruses and assemble heterogenous minigenomes into functional ribonucleoproteins (RNPs). Moreover, both heterogenous and heterozygous RNPs were efficiently packaged by viral glycoproteins into infectious virus-like particles, manifesting remarkable reassortment potential of banyangviruses. Meanwhile, UTR promoter strength of the three banyangvirus segments appeared to be M > L > S. Secondary structure analysis revealed a conservative non-basepairing protruding nucleotide in the terminal UTR panhandles of M and L (but not S) segments of all banyangviruses and some related phleboviruses (Phlebovirus genus). Furthermore, not only a conserved panhandle region but also the protruding nucleotide proved important for UTR function. Removal of the protruding nucleotide abated M and L UTR activities and compatibilities with heterogenous viral proteins, and introduction of a protruding nucleotide into S panhandle, conversely, enhanced UTR promoter strength and compatibility, revealing the significance of the protruding nucleotide as a new signature of the genomic panhandle structure in both UTR activity and reassortment potential. The study demonstrates not only banyangvirus reassortment potential but also the notable role of the protruding nucleotide in UTR function and reassortment, providing clues to viral evolution and replication mechanisms and perhaps benefiting disease control and prevention in the future.
Collapse
Affiliation(s)
- Fuli Ren
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Min Zhou
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Fei Deng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Hualin Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Yun-Jia Ning
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| |
Collapse
|
25
|
Gori Savellini G, Anichini G, Gandolfo C, Prathyumnan S, Cusi MG. Toscana virus non-structural protein NSs acts as E3 ubiquitin ligase promoting RIG-I degradation. PLoS Pathog 2019; 15:e1008186. [PMID: 31815967 PMCID: PMC6901176 DOI: 10.1371/journal.ppat.1008186] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 11/04/2019] [Indexed: 01/04/2023] Open
Abstract
It is known that the non-structural protein (NSs) of Toscana virus (TOSV), an emergent sandfly-borne virus causing meningitis or more severe central nervous system injuries in humans, exerts its function triggering RIG-I for degradation in a proteasome-dependent manner, thus breaking off the IFN-β production. The non-structural protein of different members of Bunyavirales has recently appeared as a fundamental protagonist in immunity evasion through ubiquitination-mediated protein degradation targets. We showed that TOSV NSs has an E3 ubiquitin ligase activity, mapping at the carboxy-terminal domain and also involving the amino-terminal of the protein. Indeed, neither the amino- (NSsΔN) nor the carboxy- (NSsΔC) terminal-deleted mutants of TOSV NSs were able to cause ubiquitin-mediated proteasome degradation of RIG-I. Moreover, the addition of the C-terminus of TOSV NSs to the homologous protein of the Sandfly Fever Naples Virus, belonging to the same genus and unable to inhibit IFN-β activity, conferred new properties to this protein, favoring RIG-I ubiquitination and its degradation. NSs lost its antagonistic activity to IFN when one of the terminal residues was missing. Therefore, we showed that NSs could behave as an atypical RING between RING (RBR) E3 ubiquitin ligases. This is the first report which identified the E3 ubiquitin ligase activity in a viral protein among negative strand RNA viruses.
Collapse
Affiliation(s)
| | - Gabriele Anichini
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Claudia Gandolfo
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | | | - Maria Grazia Cusi
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| |
Collapse
|
26
|
Hallam HJ, Lokugamage N, Ikegami T. Rescue of infectious Arumowot virus from cloned cDNA: Posttranslational degradation of Arumowot virus NSs protein in human cells. PLoS Negl Trop Dis 2019; 13:e0007904. [PMID: 31751340 PMCID: PMC6894884 DOI: 10.1371/journal.pntd.0007904] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 12/05/2019] [Accepted: 11/04/2019] [Indexed: 12/11/2022] Open
Abstract
Rift Valley fever (RVF) is a mosquito-borne zoonotic disease endemic to Africa and the Middle East, affecting both humans and ruminants. There are no licensed vaccines or antivirals available for humans, whereas research using RVF virus (RVFV) is strictly regulated in many countries with safety concerns. Nonpathogenic Arumowot virus (AMTV), a mosquito-borne phlebovirus in Africa, is likely useful for the screening of broad-acting antiviral candidates for phleboviruses including RVFV, as well as a potential vaccine vector for RVF. In this study, we aimed to generate T7 RNA polymerase-driven reverse genetics system for AMTV. We hypothesized that recombinant AMTV (rAMTV) is viable, and AMTV NSs protein is dispensable for efficient replication of rAMTV in type-I interferon (IFN)-incompetent cells, whereas AMTV NSs proteins support robust viral replication in type-I IFN-competent cells. The study demonstrated the rescue of rAMTV and that lacking the NSs gene (rAMTVΔNSs), that expressing green fluorescent protein (GFP) (rAMTV-GFP) or that expressing Renilla luciferase (rAMTV-rLuc) from cloned cDNA. The rAMTV-rLuc and the RVFV rMP12-rLuc showed a similar susceptibility to favipiravir or ribavirin. Interestingly, neither of rAMTV nor rAMTVΔNSs replicated efficiently in human MRC-5 or A549 cells, regardless of the presence of NSs gene. Little accumulation of AMTV NSs protein occurred in those cells, which was restored via treatment with proteasomal inhibitor MG132. In murine MEF or Hepa1-6 cells, rAMTV, but not rAMTVΔNSs, replicated efficiently, with an inhibition of IFN-β gene upregulation. This study showed an establishment of the first reverse genetics for AMTV, a lack of stability of AMTV NSs proteins in human cells, and an IFN-β gene antagonist function of AMTV NSs proteins in murine cells. The AMTV can be a nonpathogenic surrogate model for studying phleboviruses including RVFV.
Collapse
Affiliation(s)
- Hoai J. Hallam
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Nandadeva Lokugamage
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Tetsuro Ikegami
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
- Sealy Institute for Vaccine Sciences, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
- Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
- * E-mail:
| |
Collapse
|
27
|
The Leader Protein of Theiler's Virus Prevents the Activation of PKR. J Virol 2019; 93:JVI.01010-19. [PMID: 31292248 DOI: 10.1128/jvi.01010-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 07/02/2019] [Indexed: 11/20/2022] Open
Abstract
Leader (L) proteins encoded by cardioviruses are multifunctional proteins that contribute to innate immunity evasion. L proteins of Theiler's murine encephalomyelitis virus (TMEV), Saffold virus (SAFV), and encephalomyocarditis virus (EMCV) were reported to inhibit stress granule assembly in infected cells. Here, we show that TMEV L can act at two levels in the stress granule formation pathway: on the one hand, it can inhibit sodium arsenite-induced stress granule assembly without preventing eIF2α phosphorylation and, thus, acts downstream of eIF2α; on the other hand, it can inhibit eucaryotic translation initiation factor 2 alpha kinase 2 (PKR) activation and the consequent PKR-mediated eIF2α phosphorylation. Interestingly, coimmunostaining experiments revealed that PKR colocalizes with viral double-stranded RNA (dsRNA) in cells infected with L-mutant viruses but not in cells infected with the wild-type virus. Furthermore, PKR coprecipitated with dsRNA from cells infected with L-mutant viruses significantly more than from cells infected with the wild-type virus. These data strongly suggest that L blocks PKR activation by preventing the interaction between PKR and viral dsRNA. In infected cells, L also rendered PKR refractory to subsequent activation by poly(I·C). However, no interaction was observed between L and either dsRNA or PKR. Taken together, our results suggest that, unlike other viral proteins, L indirectly acts on PKR to negatively regulate its responsiveness to dsRNA.IMPORTANCE The leader (L) protein encoded by cardioviruses is a very short multifunctional protein that contributes to evasion of the host innate immune response. This protein notably prevents the formation of stress granules in infected cells. Using Theiler's virus as a model, we show that L proteins can act at two levels in the stress response pathway leading to stress granule formation, the most striking one being the inhibition of eucaryotic translation initiation factor 2 alpha kinase 2 (PKR) activation. Interestingly, the leader protein appears to inhibit PKR via a novel mechanism by rendering this kinase unable to detect double-stranded RNA, its typical activator. Unlike other viral proteins, such as influenza virus NS1, the leader protein appears to interact with neither PKR nor double-stranded RNA, suggesting that it acts indirectly to trigger the inhibition of the kinase.
Collapse
|
28
|
Du X, Meng F, Peng D, Wang Z, Ouyang W, Han Y, Gu Y, Fan L, Wu F, Jiang X, Xu F, Qin FXF. Noncanonical Role of FBXO6 in Regulating Antiviral Immunity. THE JOURNAL OF IMMUNOLOGY 2019; 203:1012-1020. [PMID: 31308089 DOI: 10.4049/jimmunol.1801557] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 06/11/2019] [Indexed: 12/16/2022]
Abstract
The evolutionarily conserved F-box family of proteins are well known for their role as the key component of SKP1-Cullin1-F-box (SCF) E3 ligase in controlling cell cycle, cell proliferation and cell death, carcinogenesis, and cancer metastasis. However, thus far, there is only limited investigation on their involvement in antiviral immunity. In contrast to the canonical function of FBXO6 associated with SCF E3 ligase complex, we report, in this study, that FBXO6 can also potently regulate the activation of IFN-I signaling during host response to viral infection by targeting the key transcription factor IFN-regulatory factor 3 (IRF3) for accelerated degradation independent of SCF in human embryonic kidney cells (HEK293T) and human lung cancer epithelial cells (A549). Structure and function delineation has further revealed that FBXO6 interacts with IAD domain of IRF3 through its FBA region to induce ubiquitination and degradation of IRF3 without the involvement of SCF. Thus, our studies have identified a general but, to our knowledge, previously unrecognized role and a novel noncanonical mechanism of FBXO6 in modulating IFN-I-mediated antiviral immune responses, which may protect the host from immunopathology of overreactive and harmful IFN-I production.
Collapse
Affiliation(s)
- Xiaohong Du
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.,Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123, China
| | - Fang Meng
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.,Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123, China
| | - Di Peng
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.,Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123, China
| | - Zining Wang
- Collaborative Innovation Center of Cancer Medicine, Department of Experimental Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Wei Ouyang
- Department of Infectious Diseases, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China; and
| | - Yu Han
- Department of Infectious Diseases, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China; and
| | - Yayun Gu
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.,Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123, China
| | - Lingbo Fan
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.,Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123, China
| | - Fei Wu
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.,Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123, China
| | - Xiaodong Jiang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520
| | - Feng Xu
- Department of Infectious Diseases, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, China; and
| | - F Xiao-Feng Qin
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China; .,Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123, China
| |
Collapse
|
29
|
Enhanced Replication of Mouse Adenovirus Type 1 following Virus-Induced Degradation of Protein Kinase R (PKR). mBio 2019; 10:mBio.00668-19. [PMID: 31015330 PMCID: PMC6479006 DOI: 10.1128/mbio.00668-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The first line of defense in cells during viral infection is the innate immune system, which is activated by different viral products. PKR is a part of this innate immune system and is induced by interferon and activated by dsRNA produced by DNA and RNA viruses. PKR is such an important part of the antiviral response that many viral families have gene products to counteract its activation or the resulting effects of its activity. Although a few RNA viruses degrade PKR, this method of counteracting PKR has not been reported for any DNA viruses. MAV-1 does not encode virus-associated RNAs, a human adenoviral defense against PKR activation. Instead, MAV-1 degrades PKR, and it is the first DNA virus reported to do so. The innate immune evasion by PKR degradation is a previously unidentified way for a DNA virus to circumvent the host antiviral response. Protein kinase R (PKR) plays a major role in activating host immunity during infection by sensing double-stranded RNA (dsRNA) produced by viruses. Once activated by dsRNA, PKR phosphorylates the translation factor eukaryotic initiation factor 2α (eIF2α), halting cellular translation. Many viruses have methods of inhibiting PKR activation or its downstream effects, circumventing protein synthesis shutdown. These include sequestering dsRNA or producing proteins that bind to and inhibit PKR activation. Here we describe our finding that in multiple cell types, PKR was depleted during mouse adenovirus type 1 (MAV-1) infection. MAV-1 did not appear to be targeting PKR at the transcriptional or translational level, because total PKR mRNA levels and levels of PKR mRNA bound to polysomes were unchanged or increased during MAV-1 infection. However, inhibiting the proteasome reduced the PKR depletion seen in MAV-1-infected cells, whereas inhibiting the lysosome had no effect. This suggests that proteasomal degradation alone is responsible for PKR degradation during MAV-1 infection. Time course experiments indicated that the degradation occurs early after infection. Infecting cells with UV-inactivated virus prevented PKR degradation, whereas inhibiting viral DNA replication did not. Together, these results suggest that an early viral gene is responsible. Degradation of PKR is a rare mechanism to oppose PKR activity, and it has been described in only six RNA viruses. To our knowledge, this is the first example of a DNA virus counteracting PKR by degrading it.
Collapse
|
30
|
Pronk MCA, Majolée J, Loregger A, van Bezu JSM, Zelcer N, Hordijk PL, Kovačević I. FBXW7 regulates endothelial barrier function by suppression of the cholesterol synthesis pathway and prenylation of RhoB. Mol Biol Cell 2019; 30:607-621. [PMID: 30601691 PMCID: PMC6589702 DOI: 10.1091/mbc.e18-04-0259] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Rho GTPases control both the actin cytoskeleton and adherens junction stability and are recognized as essential regulators of endothelial barrier function. They act as molecular switches and are primarily regulated by the exchange of GDP and GTP. However, posttranslational modifications such as phosphorylation, prenylation, and ubiquitination can additionally alter their localization, stability, and activity. F-box proteins are involved in the recognition of substrate proteins predestined for ubiquitination and subsequent degradation. Given the importance of ubiquitination, we studied the effect of the loss of 62 members of the F-box protein family on endothelial barrier function in human umbilical vein endothelial cells. Endothelial barrier function was quantified by electrical cell impedance sensing and macromolecule passage assay. Our RNA interference–based screen identified FBXW7 as a key regulator of endothelial barrier function. Mechanistically, loss of FBXW7 induced the accumulation of the RhoB GTPase in endothelial cells, resulting in their increased contractility and permeability. FBXW7 knockdown induced activation of the cholesterol biosynthesis pathway and changed the prenylation of RhoB. This effect was reversed by farnesyl transferase inhibitors and by the addition of geranylgeranyl pyrophosphate. In summary, this study identifies FBXW7 as a novel regulator of endothelial barrier function in vitro. Loss of FBXW7 indirectly modulates RhoB activity via alteration of the cholesterol biosynthesis pathway and, consequently, of the prenylation status and activity of RhoB, resulting in increased contractility and disruption of the endothelial barrier.
Collapse
Affiliation(s)
- Manon C A Pronk
- Department of Physiology, Amsterdam Cardiovascular Sciences, and
| | - Jisca Majolée
- Department of Physiology, Amsterdam Cardiovascular Sciences, and
| | - Anke Loregger
- Department of Medical Biochemistry, Amsterdam University Medical Centers, 1081 HV Amsterdam, The Netherlands
| | - Jan S M van Bezu
- Department of Physiology, Amsterdam Cardiovascular Sciences, and
| | - Noam Zelcer
- Department of Medical Biochemistry, Amsterdam University Medical Centers, 1081 HV Amsterdam, The Netherlands
| | - Peter L Hordijk
- Department of Physiology, Amsterdam Cardiovascular Sciences, and
| | - Igor Kovačević
- Department of Physiology, Amsterdam Cardiovascular Sciences, and
| |
Collapse
|
31
|
Terasaki K, Juelich TL, Smith JK, Kalveram B, Perez DD, Freiberg AN, Makino S. A single-cycle replicable Rift Valley fever phlebovirus vaccine carrying a mutated NSs confers full protection from lethal challenge in mice. Sci Rep 2018; 8:17097. [PMID: 30459418 PMCID: PMC6244155 DOI: 10.1038/s41598-018-35472-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 11/05/2018] [Indexed: 11/09/2022] Open
Abstract
Rift Valley fever phlebovirus (RVFV) is a pathogen of Rift Valley fever, which is a mosquito-borne zoonotic disease for domestic livestock and humans in African countries. Currently, no approved vaccine is available for use in non-endemic areas. The MP-12 strain is so far the best live attenuated RVFV vaccine candidate because of its good protective efficacy in animal models. However, there are safety concerns for use of MP-12 in humans. We previously developed a single-cycle replicable MP-12 (scMP-12) which lacks NSs gene and undergoes only a single round of viral replication because of its impaired ability to induce membrane-membrane fusion. In the present study, we generated an scMP-12 mutant (scMP-12-mutNSs) carrying a mutant NSs, which degrades double-stranded RNA-dependent protein kinase R but does not inhibit host transcription. Immunization of mice with a single dose (105 PFU) of scMP-12-mutNSs elicited RVFV neutralizing antibodies and high titers of anti-N IgG production and fully protected the mice from lethal wild-type RVFV challenge. Immunogenicity and protective efficacy of scMP-12-mutNSs were better than scMP-12, demonstrating that scMP-12-mutNSs is a more efficacious vaccine candidate than scMP-12. Furthermore, our data suggested that RVFV vaccine efficacy can be improved by using this specific NSs mutant.
Collapse
Affiliation(s)
- Kaori Terasaki
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States.,Institute for Human Infection and Immunity, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States
| | - Terry L Juelich
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States
| | - Jennifer K Smith
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States
| | - Birte Kalveram
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States
| | - David D Perez
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States
| | - Alexander N Freiberg
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States.,Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States.,UTMB Center for Tropical Diseases, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States.,The Sealy Institute for Vaccine Sciences, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States.,Institute for Human Infection and Immunity, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States
| | - Shinji Makino
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States. .,Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States. .,UTMB Center for Tropical Diseases, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States. .,The Sealy Institute for Vaccine Sciences, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States. .,Institute for Human Infection and Immunity, The University of Texas Medical Branch, Galveston, Texas, 77555-1019, United States.
| |
Collapse
|
32
|
NSs Protein of Sandfly Fever Sicilian Phlebovirus Counteracts Interferon (IFN) Induction by Masking the DNA-Binding Domain of IFN Regulatory Factor 3. J Virol 2018; 92:JVI.01202-18. [PMID: 30232186 PMCID: PMC6232482 DOI: 10.1128/jvi.01202-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 09/13/2018] [Indexed: 12/25/2022] Open
Abstract
Sandfly fever Sicilian virus (SFSV) is one of the most widespread and frequently identified members of the genus Phlebovirus (order Bunyavirales, family Phenuiviridae) infecting humans. Being transmitted by Phlebotomus sandflies, SFSV causes a self-limiting, acute, often incapacitating febrile disease ("sandfly fever," "Pappataci fever," or "dog disease") that has been known since at least the beginning of the 20th century. We show that, similarly to other pathogenic phleboviruses, SFSV suppresses the induction of the antiviral type I interferon (IFN) system in an NSs-dependent manner. SFSV NSs interfered with the TBK1-interferon regulatory factor 3 (IRF3) branch of the RIG-I signaling pathway but not with NF-κB activation. Consistently, we identified IRF3 as a host interactor of SFSV NSs. In contrast to IRF3, neither the IFN master regulator IRF7 nor any of the related transcription factors IRF2, IRF5, and IRF9 were bound by SFSV NSs. In spite of this specificity for IRF3, NSs did not inhibit its phosphorylation, dimerization, or nuclear accumulation, and the interaction was independent of the IRF3 activation or multimerization state. In further studies, we identified the DNA-binding domain of IRF3 (amino acids 1 to 113) as sufficient for NSs binding and found that SFSV NSs prevented the association of activated IRF3 with the IFN-β promoter. Thus, unlike highly virulent phleboviruses, which either destroy antiviral host factors or sequester whole signaling chains into inactive aggregates, SFSV modulates type I IFN induction by directly masking the DNA-binding domain of IRF3.IMPORTANCE Phleboviruses are receiving increased attention due to the constant discovery of new species and the ongoing spread of long-known members of the genus. Outbreaks of sandfly fever were reported in the 19th century, during World War I, and during World War II. Currently, SFSV is recognized as one of the most widespread phleboviruses, exhibiting high seroprevalence rates in humans and domestic animals and causing a self-limiting but incapacitating disease predominantly in immunologically naive troops and travelers. We show how the nonstructural NSs protein of SFSV counteracts the upregulation of the antiviral interferon (IFN) system. SFSV NSs specifically inhibits promoter binding by IFN transcription factor 3 (IRF3), a molecular strategy which is unique among phleboviruses and, to our knowledge, among human pathogenic RNA viruses in general. This IRF3-specific and stoichiometric mechanism, greatly distinct from the ones exhibited by the highly virulent phleboviruses, correlates with the intermediate level of pathogenicity of SFSV.
Collapse
|
33
|
Pinkham C, Ahmed A, Bracci N, Narayanan A, Kehn-Hall K. Host-based processes as therapeutic targets for Rift Valley fever virus. Antiviral Res 2018; 160:64-78. [PMID: 30316916 DOI: 10.1016/j.antiviral.2018.10.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 09/27/2018] [Accepted: 10/05/2018] [Indexed: 12/28/2022]
Abstract
Rift Valley fever virus (RVFV) is an enveloped, segmented, negative sense RNA virus that replicates within the host's cytoplasm. To facilitate its replication, RVFV must utilize host cell processes and as such, these processes may serve as potential therapeutic targets. This review summarizes key host cell processes impacted by RVFV infection. Specifically the influence of RVFV on host transcriptional regulation, post-transcriptional regulation, protein half-life and availability, host signal transduction, trafficking and secretory pathways, cytoskeletal modulation, and mitochondrial processes and oxidative stress are discussed. Therapeutics targeted towards host processes that are essential for RVFV to thrive as well as their efficacy and importance to viral pathogenesis are highlighted.
Collapse
Affiliation(s)
- Chelsea Pinkham
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - Aslaa Ahmed
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - Nicole Bracci
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - Aarthi Narayanan
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - Kylene Kehn-Hall
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA.
| |
Collapse
|
34
|
The Unique Phylogenetic Position of a Novel Tick-Borne Phlebovirus Ensures an Ixodid Origin of the Genus Phlebovirus. mSphere 2018; 3:3/3/e00239-18. [PMID: 29898985 PMCID: PMC6001614 DOI: 10.1128/msphere.00239-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 05/22/2018] [Indexed: 11/24/2022] Open
Abstract
The emergence of novel tick-borne RNA viruses causing severe illness in humans has complicated the epidemiological landscape of tick-borne diseases, requiring further investigation to safeguard public health. In the present study, we discovered a novel tick-borne phlebovirus from Ixodes persulcatus ticks in Japan. While its viral RNA genome sequences were similar to those of mosquito/sandfly-borne viruses, molecular and biological footprints confirmed that this is a tick-borne virus. The unique evolutionary position of the virus allowed us to estimate the ancestral phlebovirus vector, which was likely a hard tick. Our findings may provide a better understanding of the evolution and emergence of phleboviruses associated with emerging infectious diseases, such as severe fever with thrombocytopenia syndrome (SFTS) and Heartland virus disease. The recent emergence of novel tick-borne RNA viruses has complicated the epidemiological landscape of tick-borne infectious diseases, posing a significant challenge to public health systems that seek to counteract tick-borne diseases. The identification of two novel tick-borne phleboviruses (TBPVs), severe fever with thrombocytopenia syndrome virus (SFTSV) and Heartland virus (HRTV), as causative agents of severe illness in humans has accelerated the investigation and discoveries of novel TBPVs. In the present study, we isolated a novel TBPV designated Mukawa virus (MKWV) from host-questing Ixodes persulcatus females captured in Japan. Genetic characterization revealed that MKWV is a member of the genus Phlebovirus in the family Phenuiviridae. Interestingly, MKWV is genetically distinct from other known TBPVs and shares a most recent common ancestor with mosquito/sandfly-borne (insect-borne) phleboviruses. Despite its genetic similarity to insect-borne phleboviruses, the molecular footprints of its viral proteins and its biological characteristics define MKWV as a tick-borne virus that can be transmitted to mammals. A phylogenetic ancestral-state reconstruction for arthropod vectors of phleboviruses including MKWV based on viral L segment sequences indicated that ticks likely harbored ancestral phleboviruses that evolved into both the tick-borne and MKWV/insect-borne phlebovirus lineages. Overall, our findings suggest that most of the phlebovirus evolution has occurred in hard ticks to generate divergent viruses, which may provide a seminal foundation for understanding the mechanisms underlying the evolution and emergence of pathogenic phleboviruses, such as Rift Valley fever virus and SFTSV/HRTV. IMPORTANCE The emergence of novel tick-borne RNA viruses causing severe illness in humans has complicated the epidemiological landscape of tick-borne diseases, requiring further investigation to safeguard public health. In the present study, we discovered a novel tick-borne phlebovirus from Ixodes persulcatus ticks in Japan. While its viral RNA genome sequences were similar to those of mosquito/sandfly-borne viruses, molecular and biological footprints confirmed that this is a tick-borne virus. The unique evolutionary position of the virus allowed us to estimate the ancestral phlebovirus vector, which was likely a hard tick. Our findings may provide a better understanding of the evolution and emergence of phleboviruses associated with emerging infectious diseases, such as severe fever with thrombocytopenia syndrome (SFTS) and Heartland virus disease.
Collapse
|
35
|
Dzananovic E, McKenna SA, Patel TR. Viral proteins targeting host protein kinase R to evade an innate immune response: a mini review. Biotechnol Genet Eng Rev 2018; 34:33-59. [PMID: 29716441 DOI: 10.1080/02648725.2018.1467151] [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: 12/24/2022]
Abstract
The innate immune system offers a first line of defense by neutralizing foreign pathogens such as bacteria, fungi, and viruses. These pathogens express molecules (RNA and proteins) that have discrete structures, known as the pathogen-associated molecular patterns that are recognized by a highly specialized class of host proteins called pattern recognition receptors to facilitate the host's immune response against infection. The RNA-dependent Protein Kinase R (PKR) is one of the host's pattern recognition receptors that is a key component of an innate immune system. PKR recognizes imperfectly double-stranded non-coding viral RNA molecules via its N-terminal double-stranded RNA binding motifs, undergoes phosphorylation of the C-terminal kinase domain, ultimately resulting in inhibition of viral protein translation by inhibiting the guanine nucleotide exchange activity of eukaryotic initiation factor 2α. Not surprisingly, viruses have evolved mechanisms by which viral non-coding RNA or protein molecules inhibit PKR's activation and/or its downstream activity to allow viral replication. In this review, we will highlight the role of viral proteins in inhibiting PKR's activity and summarize currently known mechanisms by which viral proteins execute such inhibitory activity.
Collapse
Affiliation(s)
- Edis Dzananovic
- a Plant Pathology, Plant Protection and Molecular Biology , Agriculture and Agri-Food Canada , Saskatoon , Canada
| | - Sean A McKenna
- b Department of Chemistry, Manitoba Institute for Materials, Department of Biochemistry and Medical Genetics , University of Manitoba , Winnipeg , Canada
| | - Trushar R Patel
- c Department of Chemistry and Biochemistry , Alberta RNA Research and Training Institute, University of Lethbridge , Lethbridge , Canada.,d DiscoveryLab, Faculty of Medicine & Dentistry , University of Alberta , Edmonton , Canada.,e Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine , University of Calgary , Calgary , Canada
| |
Collapse
|
36
|
Alterations in the host transcriptome in vitro following Rift Valley fever virus infection. Sci Rep 2017; 7:14385. [PMID: 29085037 PMCID: PMC5662566 DOI: 10.1038/s41598-017-14800-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/16/2017] [Indexed: 01/01/2023] Open
Abstract
Rift Valley fever virus (RVFV) causes major outbreaks among livestock, characterized by "abortion storms" in which spontaneous abortion occurs in almost 100% of pregnant ruminants. Humans can also become infected with mild symptoms that can progress to more severe symptoms, such as hepatitis, encephalitis, and hemorrhagic fever. The goal of this study was to use RNA-sequencing (RNA-seq) to analyze the host transcriptome in response to RVFV infection. G2/M DNA damage checkpoint, ATM signaling, mitochondrial dysfunction, regulation of the antiviral response, and integrin-linked kinase (ILK) signaling were among the top altered canonical pathways with both the attenuated MP12 strain and the fully virulent ZH548 strain. Although several mRNA transcripts were highly upregulated, an increase at the protein level was not observed for the selected genes, which was at least partially due to the NSs dependent block in mRNA export. Inhibition of ILK signaling, which is involved in cell motility and cytoskeletal reorganization, resulted in reduced RVFV replication, indicating that this pathway is important for viral replication. Overall, this is the first global transcriptomic analysis of the human host response following RVFV infection, which could give insight into novel host responses that have not yet been explored.
Collapse
|
37
|
Mapping of Transcription Termination within the S Segment of SFTS Phlebovirus Facilitated Generation of NSs Deletant Viruses. J Virol 2017; 91:JVI.00743-17. [PMID: 28592543 PMCID: PMC5533932 DOI: 10.1128/jvi.00743-17] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 05/31/2017] [Indexed: 12/15/2022] Open
Abstract
SFTS phlebovirus (SFTSV) is an emerging tick-borne bunyavirus that was first reported in China in 2009. Here we report the generation of a recombinant SFTSV (rHB29NSsKO) that cannot express the viral nonstructural protein (NSs) upon infection of cells in culture. We show that rHB29NSsKO replication kinetics are greater in interferon (IFN)-incompetent cells and that the virus is unable to suppress IFN induced in response to viral replication. The data confirm for the first time in the context of virus infection that NSs acts as a virally encoded IFN antagonist and that NSs is dispensable for virus replication. Using 3' rapid amplification of cDNA ends (RACE), we mapped the 3' end of the N and NSs mRNAs, showing that the mRNAs terminate within the coding region of the opposite open reading frame. We show that the 3' end of the N mRNA terminates upstream of a 5'-GCCAGCC-3' motif present in the viral genomic RNA. With this knowledge, and using virus-like particles, we could demonstrate that the last 36 nucleotides of the NSs open reading frame (ORF) were needed to ensure the efficient termination of the N mRNA and were required for recombinant virus rescue. We demonstrate that it is possible to recover viruses lacking NSs (expressing just a 12-amino-acid NSs peptide or encoding enhanced green fluorescent protein [eGFP]) or an NSs-eGFP fusion protein in the NSs locus. This opens the possibility for further studies of NSs and potentially the design of attenuated viruses for vaccination studies.IMPORTANCE SFTS phlebovirus (SFTSV) and related tick-borne viruses have emerged globally since 2009. SFTSV has been shown to cause severe disease in humans. For bunyaviruses, it has been well documented that the nonstructural protein (NSs) enables the virus to counteract the human innate antiviral defenses and that NSs is one of the major determinants of virulence in infection. Therefore, the use of reverse genetics systems to engineer viruses lacking NSs is an attractive strategy to rationally attenuate bunyaviruses. Here we report the generation of several recombinant SFTS viruses that cannot express the NSs protein or have the NSs open reading frame replaced with a reporter gene. These viruses cannot antagonize the mammalian interferon (IFN) response mounted to virus infection. The generation of NSs-lacking viruses was achieved by mapping the transcriptional termination of two S-segment-derived subgenomic mRNAs, which revealed that transcription termination occurs upstream of a 5'-GCCAGCC-3' motif present in the virus genomic S RNA.
Collapse
|
38
|
Differential Antagonism of Human Innate Immune Responses by Tick-Borne Phlebovirus Nonstructural Proteins. mSphere 2017; 2:mSphere00234-17. [PMID: 28680969 PMCID: PMC5489658 DOI: 10.1128/msphere.00234-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 06/05/2017] [Indexed: 12/24/2022] Open
Abstract
In recent years, several newly discovered tick-borne viruses causing a wide spectrum of diseases in humans have been ascribed to the Phlebovirus genus of the Bunyaviridae family. The nonstructural protein (NSs) of bunyaviruses is the main virulence factor and interferon (IFN) antagonist. We studied the molecular mechanisms of IFN antagonism employed by the NSs proteins of human apathogenic Uukuniemi virus (UUKV) and those of Heartland virus (HRTV) and severe fever with thrombocytopenia syndrome virus (SFTSV), both of which cause severe disease. Using reporter assays, we found that UUKV NSs weakly inhibited the activation of the beta interferon (IFN-β) promoter and response elements. UUKV NSs weakly antagonized human IFN-β promoter activation through a novel interaction with mitochondrial antiviral-signaling protein (MAVS), confirmed by coimmunoprecipitation and confocal microscopy studies. HRTV NSs efficiently antagonized both IFN-β promoter activation and type I IFN signaling pathways through interactions with TBK1, preventing its phosphorylation. HRTV NSs exhibited diffused cytoplasmic localization. This is in comparison to the inclusion bodies formed by SFTSV NSs. HRTV NSs also efficiently interacted with STAT2 and impaired IFN-β-induced phosphorylation but did not affect STAT1 or its translocation to the nucleus. Our results suggest that a weak interaction between STAT1 and HRTV or SFTSV NSs may explain their inability to block type II IFN signaling efficiently, thus enabling the activation of proinflammatory responses that lead to severe disease. Our findings offer insights into how pathogenicity may be linked to the capacity of NSs proteins to block the innate immune system and illustrate the plethora of viral immune evasion strategies utilized by emerging phleboviruses. IMPORTANCE Since 2011, there has been a large expansion in the number of emerging tick-borne viruses that have been assigned to the Phlebovirus genus. Heartland virus (HRTV) and SFTS virus (SFTSV) were found to cause severe disease in humans, unlike other documented tick-borne phleboviruses such as Uukuniemi virus (UUKV). Phleboviruses encode nonstructural proteins (NSs) that enable them to counteract the human innate antiviral defenses. We assessed how these proteins interacted with the innate immune system. We found that UUKV NSs engaged with innate immune factors only weakly, at one early step. However, the viruses that cause more severe disease efficiently disabled the antiviral response by targeting multiple components at several stages across the innate immune induction and signaling pathways. Our results suggest a correlation between the efficiency of the virus protein/host interaction and severity of disease.
Collapse
|
39
|
Attacked from All Sides: RNA Decay in Antiviral Defense. Viruses 2017; 9:v9010002. [PMID: 28054965 PMCID: PMC5294971 DOI: 10.3390/v9010002] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/22/2016] [Accepted: 12/26/2016] [Indexed: 12/22/2022] Open
Abstract
The innate immune system has evolved a number of sensors that recognize viral RNA (vRNA) to restrict infection, yet the full spectrum of host-encoded RNA binding proteins that target these foreign RNAs is still unknown. The RNA decay machinery, which uses exonucleases to degrade aberrant RNAs largely from the 5′ or 3′ end, is increasingly recognized as playing an important role in antiviral defense. The 5′ degradation pathway can directly target viral messenger RNA (mRNA) for degradation, as well as indirectly attenuate replication by limiting specific pools of endogenous RNAs. The 3′ degradation machinery (RNA exosome) is emerging as a downstream effector of a diverse array of vRNA sensors. This review discusses our current understanding of the roles of the RNA decay machinery in controlling viral infection.
Collapse
|
40
|
Terasaki K, Ramirez SI, Makino S. Mechanistic Insight into the Host Transcription Inhibition Function of Rift Valley Fever Virus NSs and Its Importance in Virulence. PLoS Negl Trop Dis 2016; 10:e0005047. [PMID: 27711108 PMCID: PMC5053439 DOI: 10.1371/journal.pntd.0005047] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 09/17/2016] [Indexed: 11/18/2022] Open
Abstract
Rift Valley fever virus (RVFV), a member of the genus Phlebovirus within the family Bunyaviridae, causes periodic outbreaks in livestocks and humans in countries of the African continent and Middle East. RVFV NSs protein, a nonstructural protein, is a major virulence factor that exhibits several important biological properties. These include suppression of general transcription, inhibition of IFN-β promoter induction and degradation of double-stranded RNA-dependent protein kinase R. Although each of these biological functions of NSs are considered important for countering the antiviral response in the host, the individual contributions of these functions towards RVFV virulence remains unclear. To examine this, we generated two RVFV MP-12 strain-derived mutant viruses. Each carried mutations in NSs that specifically targeted its general transcription inhibition function without affecting its ability to degrade PKR and inhibit IFN-β promoter induction, through its interaction with Sin3-associated protein 30, a part of the repressor complex at the IFN-β promoter. Using these mutant viruses, we have dissected the transcription inhibition function of NSs and examined its importance in RVFV virulence. Both NSs mutant viruses exhibited a differentially impaired ability to inhibit host transcription when compared with MP-12. It has been reported that NSs suppresses general transcription by interfering with the formation of the transcription factor IIH complex, through the degradation of the p62 subunit and sequestration of the p44 subunit. Our study results lead us to suggest that the ability of NSs to induce p62 degradation is the major contributor to its general transcription inhibition property, whereas its interaction with p44 may not play a significant role in this function. Importantly, RVFV MP-12-NSs mutant viruses with an impaired general transcription inhibition function showed a reduced cytotoxicity in cell culture and attenuated virulence in young mice, compared with its parental virus MP-12, highlighting the contribution of NSs-mediated general transcription inhibition towards RVFV virulence. Rift Valley fever virus (RVFV) has a significant impact on the livestock industry because of its high mortality rate in young ruminants and causation of a high abortion rate in pregnant animals. Human RVFV infections generally manifest as self-limiting and non-fatal illnesses. However, a small percentage of patients develop encephalitis, vision loss and hemorrhagic fever with a high mortality rate. Currently, there is no commercially available vaccine for human use or effective antiviral drug for RVFV treatment. The non-structural protein NSs is a major virulence factor of RVFV, which mediates suppression of host general transcription, inhibition of IFN-β transcription and degradation of PKR, to block host antiviral responses. To examine the contribution of host transcription inhibition to RVFV virulence, we generated RVFV MP-12 strain-derived mutants that have attenuated inhibitory activity on host transcription due to amino acid mutations in NSs. The mutant viruses showed attenuated cytotoxicity in cell culture and attenuated virulence in young mice, demonstrating the contribution of NSs-mediated host transcription inhibition to the virulence of RVFV.
Collapse
Affiliation(s)
- Kaori Terasaki
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Sydney I. Ramirez
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Shinji Makino
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas, United States of America
- UTMB Center for Tropical Diseases, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Sealy Center for Vaccine Development, The University of Texas Medical Branch, Galveston, Texas, United States of America
- The Institute for Human Infections and Immunity, The University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail:
| |
Collapse
|
41
|
Ly HJ, Ikegami T. Rift Valley fever virus NSs protein functions and the similarity to other bunyavirus NSs proteins. Virol J 2016; 13:118. [PMID: 27368371 PMCID: PMC4930582 DOI: 10.1186/s12985-016-0573-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 06/23/2016] [Indexed: 12/31/2022] Open
Abstract
Rift Valley fever is a mosquito-borne zoonotic disease that affects both ruminants and humans. The nonstructural (NS) protein, which is a major virulence factor for Rift Valley fever virus (RVFV), is encoded on the S-segment. Through the cullin 1-Skp1-Fbox E3 ligase complex, the NSs protein promotes the degradation of at least two host proteins, the TFIIH p62 and the PKR proteins. NSs protein bridges the Fbox protein with subsequent substrates, and facilitates the transfer of ubiquitin. The SAP30-YY1 complex also bridges the NSs protein with chromatin DNA, affecting cohesion and segregation of chromatin DNA as well as the activation of interferon-β promoter. The presence of NSs filaments in the nucleus induces DNA damage responses and causes cell-cycle arrest, p53 activation, and apoptosis. Despite the fact that NSs proteins have poor amino acid similarity among bunyaviruses, the strategy utilized to hijack host cells are similar. This review will provide and summarize an update of recent findings pertaining to the biological functions of the NSs protein of RVFV as well as the differences from those of other bunyaviruses.
Collapse
Affiliation(s)
- Hoai J Ly
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Tetsuro Ikegami
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA. .,The Sealy Center for Vaccine Development, The University of Texas Medical Branch at Galveston, Galveston, TX, USA. .,The Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch at Galveston, Galveston, TX, USA.
| |
Collapse
|
42
|
Wuerth JD, Weber F. Phleboviruses and the Type I Interferon Response. Viruses 2016; 8:v8060174. [PMID: 27338447 PMCID: PMC4926194 DOI: 10.3390/v8060174] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Revised: 06/15/2016] [Accepted: 06/20/2016] [Indexed: 12/16/2022] Open
Abstract
The genus Phlebovirus of the family Bunyaviridae contains a number of emerging virus species which pose a threat to both human and animal health. Most prominent members include Rift Valley fever virus (RVFV), sandfly fever Naples virus (SFNV), sandfly fever Sicilian virus (SFSV), Toscana virus (TOSV), Punta Toro virus (PTV), and the two new members severe fever with thrombocytopenia syndrome virus (SFTSV) and Heartland virus (HRTV). The nonstructural protein NSs is well established as the main phleboviral virulence factor in the mammalian host. NSs acts as antagonist of the antiviral type I interferon (IFN) system. Recent progress in the elucidation of the molecular functions of a growing list of NSs proteins highlights the astonishing variety of strategies employed by phleboviruses to evade the IFN system.
Collapse
Affiliation(s)
- Jennifer Deborah Wuerth
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen 35392, Germany.
| | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen 35392, Germany.
| |
Collapse
|