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Abedeera SM, Davila-Calderon J, Haddad C, Henry B, King J, Penumutchu S, Tolbert BS. The Repurposing of Cellular Proteins during Enterovirus A71 Infection. Viruses 2023; 16:75. [PMID: 38257775 PMCID: PMC10821071 DOI: 10.3390/v16010075] [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: 12/09/2023] [Revised: 12/27/2023] [Accepted: 12/29/2023] [Indexed: 01/24/2024] Open
Abstract
Viruses pose a great threat to people's lives. Enterovirus A71 (EV-A71) infects children and infants all over the world with no FDA-approved treatment to date. Understanding the basic mechanisms of viral processes aids in selecting more efficient drug targets and designing more effective antivirals to thwart this virus. The 5'-untranslated region (5'-UTR) of the viral RNA genome is composed of a cloverleaf structure and an internal ribosome entry site (IRES). Cellular proteins that bind to the cloverleaf structure regulate viral RNA synthesis, while those that bind to the IRES also known as IRES trans-acting factors (ITAFs) regulate viral translation. In this review, we survey the cellular proteins currently known to bind the 5'-UTR and influence viral gene expression with emphasis on comparing proteins' functions and localizations pre- and post-(EV-A71) infection. A comprehensive understanding of how the host cell's machinery is hijacked and reprogrammed by the virus to facilitate its replication is crucial for developing effective antivirals.
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Affiliation(s)
- Sudeshi M. Abedeera
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (S.M.A.); (B.H.); (S.P.)
| | - Jesse Davila-Calderon
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA; (J.D.-C.); (C.H.); (J.K.)
| | - Christina Haddad
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA; (J.D.-C.); (C.H.); (J.K.)
| | - Barrington Henry
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (S.M.A.); (B.H.); (S.P.)
| | - Josephine King
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA; (J.D.-C.); (C.H.); (J.K.)
| | - Srinivasa Penumutchu
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (S.M.A.); (B.H.); (S.P.)
| | - Blanton S. Tolbert
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (S.M.A.); (B.H.); (S.P.)
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
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González Aparicio LJ, Yang Y, Hackbart M, López CB. Copy-back viral genomes induce a cellular stress response that interferes with viral protein expression without affecting antiviral immunity. PLoS Biol 2023; 21:e3002381. [PMID: 37983241 PMCID: PMC10695362 DOI: 10.1371/journal.pbio.3002381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 12/04/2023] [Accepted: 10/15/2023] [Indexed: 11/22/2023] Open
Abstract
Antiviral responses are often accompanied by translation inhibition and formation of stress granules (SGs) in infected cells. However, the triggers for these processes and their role during infection remain subjects of active investigation. Copy-back viral genomes (cbVGs) are the primary inducers of the mitochondrial antiviral signaling (MAVS) pathway and antiviral immunity during Sendai virus (SeV) and respiratory syncytial virus (RSV) infections. The relationship between cbVGs and cellular stress during viral infections is unknown. Here, we show that SGs form during infections containing high levels of cbVGs, and not during infections with low levels of cbVGs. Moreover, using RNA fluorescent in situ hybridization to differentiate accumulation of standard viral genomes from cbVGs at a single-cell level during infection, we show that SGs form exclusively in cells that accumulate high levels of cbVGs. Protein kinase R (PKR) activation is increased during high cbVG infections and, as expected, is necessary for virus-induced SGs. However, SGs form independent of MAVS signaling, demonstrating that cbVGs induce antiviral immunity and SG formation through 2 independent mechanisms. Furthermore, we show that translation inhibition and SG formation do not affect the overall expression of interferon and interferon stimulated genes during infection, making the stress response dispensable for global antiviral immunity. Using live-cell imaging, we show that SG formation is highly dynamic and correlates with a drastic reduction of viral protein expression even in cells infected for several days. Through analysis of active protein translation at a single-cell level, we show that infected cells that form SGs show inhibition of protein translation. Together, our data reveal a new cbVG-driven mechanism of viral interference where cbVGs induce PKR-mediated translation inhibition and SG formation, leading to a reduction in viral protein expression without altering overall antiviral immunity.
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Affiliation(s)
- Lavinia J. González Aparicio
- Department of Molecular Microbiology and Center for Women Infectious Disease Research, Washington University School of Medicine in St. Louis, Missouri, United States of America
| | - Yanling Yang
- Department of Molecular Microbiology and Center for Women Infectious Disease Research, Washington University School of Medicine in St. Louis, Missouri, United States of America
| | - Matthew Hackbart
- Department of Molecular Microbiology and Center for Women Infectious Disease Research, Washington University School of Medicine in St. Louis, Missouri, United States of America
| | - Carolina B. López
- Department of Molecular Microbiology and Center for Women Infectious Disease Research, Washington University School of Medicine in St. Louis, Missouri, United States of America
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Alston JJ, Soranno A. Condensation Goes Viral: A Polymer Physics Perspective. J Mol Biol 2023; 435:167988. [PMID: 36709795 PMCID: PMC10368797 DOI: 10.1016/j.jmb.2023.167988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023]
Abstract
The past decade has seen a revolution in our understanding of how the cellular environment is organized, where an incredible body of work has provided new insights into the role played by membraneless organelles. These rapid advancements have been made possible by an increasing awareness of the peculiar physical properties that give rise to such bodies and the complex biology that enables their function. Viral infections are not extraneous to this. Indeed, in host cells, viruses can harness existing membraneless compartments or, even, induce the formation of new ones. By hijacking the cellular machinery, these intracellular bodies can assist in the replication, assembly, and packaging of the viral genome as well as in the escape of the cellular immune response. Here, we provide a perspective on the fundamental polymer physics concepts that may help connect and interpret the different observed phenomena, ranging from the condensation of viral genomes to the phase separation of multicomponent solutions. We complement the discussion of the physical basis with a description of biophysical methods that can provide quantitative insights for testing and developing theoretical and computational models.
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Affiliation(s)
- Jhullian J Alston
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 St Euclid Ave, 63110 Saint Louis, MO, USA; Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130 Saint Louis, MO, USA
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 St Euclid Ave, 63110 Saint Louis, MO, USA; Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130 Saint Louis, MO, USA.
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4
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Lopez CB, Gonzalez Aparicio LJ, Yang Y, Hackbart MS. Copy-back viral genomes induce a cellular stress response that interferes with viral protein expression without affecting antiviral immunity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.17.541157. [PMID: 37292625 PMCID: PMC10245731 DOI: 10.1101/2023.05.17.541157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Antiviral responses are often accompanied by translation inhibition and formation of stress granules (SG) in infected cells. However, the triggers for these processes and their role during infection remain subjects of active investigation. Copy-back viral genomes (cbVGs) are the primary inducers of the Mitochondrial Antiviral Signaling (MAVS) pathway and antiviral immunity during Sendai Virus (SeV) and Respiratory Syncytial virus (RSV) infections. The relationship between cbVGs and cellular stress during viral infections is unknown. Here we show that SG form during infections containing high levels of cbVGs, and not during infections with low levels of cbVGs. Moreover, using RNA fluorescent in situ hybridization to differentiate accumulation of standard viral genomes from cbVGs at a single-cell level during infection, we show that SG form exclusively in cells that accumulate high levels of cbVGs. PKR activation is increased during high cbVG infections and, as expected, PKR is necessary to induce virus-induced SG. However, SG form independent of MAVS signaling, demonstrating that cbVGs induce antiviral immunity and SG formation through two independent mechanisms. Furthermore, we show that translation inhibition and SG formation do not affect the overall expression of interferon and interferon stimulated genes during infection, making the stress response dispensable for antiviral immunity. Using live-cell imaging, we show that SG formation is highly dynamic and correlates with a drastic reduction of viral protein expression even in cells infected for several days. Through analysis of active protein translation at a single cell level, we show that infected cells that form SG show inhibition of protein translation. Together, our data reveal a new cbVG-driven mechanism of viral interference where cbVGs induce PKR-mediated translation inhibition and SG formation leading to a reduction in viral protein expression without altering overall antiviral immunity.
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5
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Liu Y, Yao Z, Lian G, Yang P. Biomolecular phase separation in stress granule assembly and virus infection. Acta Biochim Biophys Sin (Shanghai) 2023; 55:1099-1118. [PMID: 37401177 PMCID: PMC10415189 DOI: 10.3724/abbs.2023117] [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: 12/28/2022] [Accepted: 05/06/2023] [Indexed: 07/05/2023] Open
Abstract
Liquid-liquid phase separation (LLPS) has emerged as a crucial mechanism for cellular compartmentalization. One prominent example of this is the stress granule. Found in various types of cells, stress granule is a biomolecular condensate formed through phase separation. It comprises numerous RNA and RNA-binding proteins. Over the past decades, substantial knowledge has been gained about the composition and dynamics of stress granules. SGs can regulate various signaling pathways and have been associated with numerous human diseases, such as neurodegenerative diseases, cancer, and infectious diseases. The threat of viral infections continues to loom over society. Both DNA and RNA viruses depend on host cells for replication. Intriguingly, many stages of the viral life cycle are closely tied to RNA metabolism in human cells. The field of biomolecular condensates has rapidly advanced in recent times. In this context, we aim to summarize research on stress granules and their link to viral infections. Notably, stress granules triggered by viral infections behave differently from the canonical stress granules triggered by sodium arsenite (SA) and heat shock. Studying stress granules in the context of viral infections could offer a valuable platform to link viral replication processes and host anti-viral responses. A deeper understanding of these biological processes could pave the way for innovative interventions and treatments for viral infectious diseases. They could potentially bridge the gap between basic biological processes and interactions between viruses and their hosts.
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Affiliation(s)
- Yi Liu
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Zhiying Yao
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Guiwei Lian
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Peiguo Yang
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
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6
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Romero-López C, Roda-Herreros M, Berzal-Herranz B, Ramos-Lorente SE, Berzal-Herranz A. Inter- and Intramolecular RNA–RNA Interactions Modulate the Regulation of Translation Mediated by the 3′ UTR in West Nile Virus. Int J Mol Sci 2023; 24:ijms24065337. [PMID: 36982407 PMCID: PMC10049277 DOI: 10.3390/ijms24065337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/06/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023] Open
Abstract
RNA viruses rely on genomic structural elements to accomplish the functions necessary to complete the viral cycle. These elements participate in a dynamic network of RNA–RNA interactions that determine the overall folding of the RNA genome and may be responsible for the fine regulation of viral replication and translation as well as the transition between them. The genomes of members of the genus Flavivirus are characterized by a complexly folded 3′ UTR with a number of RNA structural elements that are conserved across isolates of each species. The present work provides evidence of intra- and intermolecular RNA–RNA interactions involving RNA structural elements in the 3′ UTR of the West Nile virus genome. The intermolecular interactions can be visualized in vitro by the formation of molecular dimers involving the participation of at least the SLI and 3′DB elements. Certainly, the 3′ UTR of dengue virus, which lacks the SLI element, forms molecular dimers in lower quantities via a single interaction site, probably 3′DB. The functional analysis of sequence or deletion mutants revealed an inverse relationship between 3′ UTR dimerization and viral translation efficiency in cell cultures. A network of RNA–RNA interactions involving 3′ UTR structural elements might therefore exist, helping to regulate viral translation.
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Guan Y, Wang Y, Fu X, Bai G, Li X, Mao J, Yan Y, Hu L. Multiple functions of stress granules in viral infection at a glance. Front Microbiol 2023; 14:1138864. [PMID: 36937261 PMCID: PMC10014870 DOI: 10.3389/fmicb.2023.1138864] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 02/08/2023] [Indexed: 03/05/2023] Open
Abstract
Stress granules (SGs) are distinct RNA granules induced by various stresses, which are evolutionarily conserved across species. In general, SGs act as a conservative and essential self-protection mechanism during stress responses. Viruses have a long evolutionary history and viral infections can trigger a series of cellular stress responses, which may interact with SG formation. Targeting SGs is believed as one of the critical and conservative measures for viruses to tackle the inhibition of host cells. In this systematic review, we have summarized the role of SGs in viral infection and categorized their relationships into three tables, with a particular focus on Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Moreover, we have outlined several kinds of drugs targeting SGs according to different pathways, most of which are potentially effective against SARS-CoV-2. We believe this review would offer a new view for the researchers and clinicians to attempt to develop more efficacious treatments for virus infection, particularly for the treatment of SARS-CoV-2 infection.
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Affiliation(s)
- Yuelin Guan
- The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yan Wang
- The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Xudong Fu
- Center of Stem Cell and Regenerative Medicine, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Zhejiang Laboratory for Systems and Precision Medicine, Zhejiang University Medical Center, Hangzhou, Zhejiang, China
| | - Guannan Bai
- The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Xue Li
- Department of Big Data in Health Science School of Public Health and The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jianhua Mao
- The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yongbin Yan
- State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing, China
- *Correspondence: Yongbin Yan,
| | - Lidan Hu
- The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
- Lidan Hu,
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Wang L, Guzmán M, Sola I, Enjuanes L, Zuñiga S. Cytoplasmic ribonucleoprotein complexes, RNA helicases and coronavirus infection. FRONTIERS IN VIROLOGY 2022. [DOI: 10.3389/fviro.2022.1078454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
RNA metabolism in the eukaryotic cell includes the formation of ribonucleoprotein complexes (RNPs) that, depending on their protein components, have a different function. Cytoplasmic RNPs, such as stress granules (SGs) or P-bodies (PBs) are quite relevant during infections modulating viral and cellular RNA expression and as key players in the host cell antiviral response. RNA helicases are abundant components of RNPs and could have a significant effect on viral infection. This review focuses in the role that RNPs and RNA helicases have during coronavirus (CoVs) infection. CoVs are emerging highly pathogenic viruses with a large single-stranded RNA genome. During CoV infection, a complex network of RNA-protein interactions in different RNP structures is established. In general, RNA helicases and RNPs have an antiviral function, but there is limited knowledge on whether the viral protein interactions with cell components are mediators of this antiviral effect or are part of the CoV antiviral counteraction mechanism. Additional data is needed to elucidate the role of these RNA-protein interactions during CoV infection and their potential contribution to viral replication or pathogenesis.
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Moghimi S, Viktorova EG, Gabaglio S, Zimina A, Budnik B, Wynn BG, Sztul E, Belov GA. A Proximity biotinylation assay with a host protein bait reveals multiple factors modulating enterovirus replication. PLoS Pathog 2022; 18:e1010906. [PMID: 36306280 PMCID: PMC9645661 DOI: 10.1371/journal.ppat.1010906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 11/09/2022] [Accepted: 09/30/2022] [Indexed: 11/07/2022] Open
Abstract
As ultimate parasites, viruses depend on host factors for every step of their life cycle. On the other hand, cells evolved multiple mechanisms of detecting and interfering with viral replication. Yet, our understanding of the complex ensembles of pro- and anti-viral factors is very limited in virtually every virus-cell system. Here we investigated the proteins recruited to the replication organelles of poliovirus, a representative of the genus Enterovirus of the Picornaviridae family. We took advantage of a strict dependence of enterovirus replication on a host protein GBF1, and established a stable cell line expressing a truncated GBF1 fused to APEX2 peroxidase that effectively supported viral replication upon inhibition of the endogenous GBF1. This construct biotinylated multiple host and viral proteins on the replication organelles. Among the viral proteins, the polyprotein cleavage intermediates were overrepresented, suggesting that the GBF1 environment is linked to viral polyprotein processing. The proteomics characterization of biotinylated host proteins identified multiple proteins previously associated with enterovirus replication, as well as more than 200 new factors recruited to the replication organelles. RNA metabolism proteins, many of which normally localize in the nucleus, constituted the largest group, underscoring the massive release of nuclear factors into the cytoplasm of infected cells and their involvement in viral replication. Functional analysis of several newly identified proteins revealed both pro- and anti-viral factors, including a novel component of infection-induced stress granules. Depletion of these proteins similarly affected the replication of diverse enteroviruses indicating broad conservation of the replication mechanisms. Thus, our data significantly expand the knowledge of the composition of enterovirus replication organelles, provide new insights into viral replication, and offer a novel resource for identifying targets for anti-viral interventions.
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Affiliation(s)
- Seyedehmahsa Moghimi
- Department of Veterinary Medicine and Virginia-Maryland College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
| | - Ekaterina G. Viktorova
- Department of Veterinary Medicine and Virginia-Maryland College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
| | - Samuel Gabaglio
- Department of Veterinary Medicine and Virginia-Maryland College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
| | - Anna Zimina
- Department of Veterinary Medicine and Virginia-Maryland College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
| | - Bogdan Budnik
- Mass Spectrometry and Proteomics Resource Laboratory (MSPRL), FAS Division of Science, Harvard University, Cambridge, Massachusetts, United States of America
| | - Bridge G. Wynn
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham; Birmingham, Alabama, United States of America
| | - Elizabeth Sztul
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham; Birmingham, Alabama, United States of America
| | - George A. Belov
- Department of Veterinary Medicine and Virginia-Maryland College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
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Role of Stress Granules in Suppressing Viral Replication by the Infectious Bronchitis Virus Endoribonuclease. J Virol 2022; 96:e0068622. [PMID: 35638780 DOI: 10.1128/jvi.00686-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infectious bronchitis virus (IBV), a γ-coronavirus, causes the economically important poultry disease infectious bronchitis. Cellular stress response is an effective antiviral strategy that leads to stress granule (SG) formation. Previous studies suggested that SGs were involved in the antiviral activity of host cells to limit viral propagation. Here, we aimed to delineate the molecular mechanisms regulating the SG response to pathogenic IBV strain infection. We found that most chicken embryo kidney (CEK) cells formed no SGs during IBV infection and IBV replication inhibited arsenite-induced SG formation. This inhibition was not caused by changes in the integrity or abundance of SG proteins during infection. IBV nonstructural protein 15 (Nsp15) endoribonuclease activity suppressed SG formation. Regardless of whether Nsp15 was expressed alone, with recombinant viral infection with Newcastle disease virus as a vector, or with EndoU-deficient IBV, the Nsp15 endoribonuclease activity was the main factor inhibiting SG formation. Importantly, uridine-specific endoribonuclease (EndoU)-deficient IBV infection induced colocalization of IBV N protein/dsRNA and SG-associated protein TIA1 in infected cells. Additionally, overexpressing TIA1 in CEK cells suppressed IBV replication and may be a potential antiviral factor for impairing viral replication. These data provide a novel foundation for future investigations of the mechanisms by which coronavirus endoribonuclease activity affects viral replication. IMPORTANCE Endoribonuclease is conserved in coronaviruses and affects viral replication and pathogenicity. Infectious bronchitis virus (IBV), a γ-coronavirus, infects respiratory, renal, and reproductive systems, causing millions of dollars in lost revenue to the poultry industry worldwide annually. Mutating the viral endoribonuclease poly(U) resulted in SG formation, and TIA1 protein colocalized with the viral N protein and dsRNA, thus damaging IBV replication. These results suggest a new antiviral target design strategy for coronaviruses.
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11
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Hassan W, Noreen H, Rehman S, Kamal MA, Teixeira da Rocha JB. Association of Oxidative Stress with Neurological Disorders. Curr Neuropharmacol 2022; 20:1046-1072. [PMID: 34781871 PMCID: PMC9886831 DOI: 10.2174/1570159x19666211111141246] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 09/05/2021] [Accepted: 10/06/2021] [Indexed: 11/22/2022] Open
Abstract
BACKGORUND Oxidative stress is one of the main contributing factors involved in cerebral biochemical impairment. The higher susceptibility of the central nervous system to reactive oxygen species mediated damage could be attributed to several factors. For example, neurons use a greater quantity of oxygen, many parts of the brain have higher concentraton of iron, and neuronal mitochondria produce huge content of hydrogen peroxide. In addition, neuronal membranes have polyunsaturated fatty acids, which are predominantly vulnerable to oxidative stress (OS). OS is the imbalance between reactive oxygen species generation and cellular antioxidant potential. This may lead to various pathological conditions and diseases, especially neurodegenerative diseases such as, Parkinson's, Alzheimer's, and Huntington's diseases. OBJECTIVES In this study, we explored the involvement of OS in neurodegenerative diseases. METHODS We used different search terms like "oxidative stress and neurological disorders" "free radicals and neurodegenerative disorders" "oxidative stress, free radicals, and neurological disorders" and "association of oxidative stress with the name of disorders taken from the list of neurological disorders. We tried to summarize the source, biological effects, and physiologic functions of ROS. RESULTS Finally, it was noted that more than 190 neurological disorders are associated with oxidative stress. CONCLUSION More elaborated studies in the future will certainly help in understanding the exact mechanism involved in neurological diseases and provide insight into revelation of therapeutic targets.
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Affiliation(s)
- Waseem Hassan
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pakhtunkhwa, Pakistan;,Address correspondence to this author at the Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pakhtunkhwa, Pakistan; E-mail:
| | - Hamsa Noreen
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pakhtunkhwa, Pakistan
| | - Shakila Rehman
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pakhtunkhwa, Pakistan
| | - Mohammad Amjad Kamal
- King Fahd Medical Research Center, King Abdulaziz University, P. O. Box 80216, Jeddah 21589, Saudi Arabia;,Enzymoics, 7 Peterlee Place, Hebersham, NSW 2770, Australia
| | - Joao Batista Teixeira da Rocha
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-Graduação em Bioquímica, Toxicológica, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil
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12
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Sun M, Wu S, Zhang X, Liu Z, Zhang L, Kang S, Liao J, Liu M, Qin Q, Wei J. Grouper TIA-1 functions as a crucial antiviral molecule against nervous necrosis virus infection. FISH & SHELLFISH IMMUNOLOGY 2022; 121:478-486. [PMID: 35085738 DOI: 10.1016/j.fsi.2022.01.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/21/2022] [Accepted: 01/22/2022] [Indexed: 06/14/2023]
Abstract
T-cell intracellular antigen (TIA)-1 is a prion-related RNA-binding protein involved in splicing and translational repression, and regulates translation in response to stress conditions by isolating target mRNAs in stress granules (SGs). However, little is known about the potential roles of fish TIA-1 and how it works in viral infection. In this study, the TIA-1 (EcTIA-1) homolog from orange-spotted grouper (Epinephelus coioides) was cloned and characterized. The open reading frame (ORF) sequence of EcTIA-1 encoded a 388 amino acid protein with predicted molecular mass of 42.73 kDa. EcTIA-1 contains three conserved domains of RNA recognition motif (RRM) that may interact with RNA via its second and third RRMs. Overexpression of EcTIA-1 inhibited red-spotted grouper nervous necrosis virus (RGNNV) replication and positively regulated interferon immune response, which was increased by knockdown of EcTIA-1. RGNNV induced formation of SGs in cells with EcTIA-1 overexpression. These results provide a novel insight into understanding the roles of fish TIA-1 in response to RNA viruses.
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Affiliation(s)
- Mengshi Sun
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Siting Wu
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Xin Zhang
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Zetian Liu
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Luhao Zhang
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Shaozhu Kang
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Jiaming Liao
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Mengke Liu
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China
| | - Qiwei Qin
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China; Guangdong Laboratory for Lingnan Modern Agriculture, PR China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266000, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), 528478, PR China.
| | - Jingguang Wei
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, PR China.
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13
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The Multifunctional Faces of T-Cell Intracellular Antigen 1 in Health and Disease. Int J Mol Sci 2022; 23:ijms23031400. [PMID: 35163320 PMCID: PMC8836218 DOI: 10.3390/ijms23031400] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/13/2022] [Accepted: 01/22/2022] [Indexed: 02/06/2023] Open
Abstract
T-cell intracellular antigen 1 (TIA1) is an RNA-binding protein that is expressed in many tissues and in the vast majority of species, although it was first discovered as a component of human cytotoxic T lymphocytes. TIA1 has a dual localization in the nucleus and cytoplasm, where it plays an important role as a regulator of gene-expression flux. As a multifunctional master modulator, TIA1 controls biological processes relevant to the physiological functioning of the organism and the development and/or progression of several human pathologies. This review summarizes our current knowledge of the molecular aspects and cellular processes involving TIA1, with relevance for human pathophysiology.
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14
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Gerassimovich YA, Miladinovski-Bangall SJ, Bridges KM, Boateng L, Ball LE, Valafar H, Nag A. Proximity-dependent biotinylation detects associations between SARS coronavirus nonstructural protein 1 and stress granule-associated proteins. J Biol Chem 2021; 297:101399. [PMID: 34774526 PMCID: PMC8580555 DOI: 10.1016/j.jbc.2021.101399] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 10/28/2021] [Accepted: 11/08/2021] [Indexed: 11/17/2022] Open
Abstract
The nonstructural protein 1 (nsp1) of severe acute respiratory syndrome coronavirus and severe acute respiratory syndrome coronavirus 2 is a critical viral protein that suppresses host gene expression by blocking the assembly of the ribosome on host mRNAs. To understand the mechanism of inhibition of host gene expression, we sought to identify cellular proteins that interact with nsp1. Using proximity-dependent biotinylation followed by proteomic analyses of biotinylated proteins, here we captured multiple dynamic interactions of nsp1 with host cell proteins. In addition to ribosomal proteins, we identified several pre-mRNA processing proteins that interact with nsp1, including splicing factors and transcription termination proteins, as well as exosome, and stress granule (SG)-associated proteins. We found that the interactions with transcription termination factors are primarily governed by the C-terminal region of nsp1 and are disrupted by the mutation of amino acids K164 and H165 that are essential for its host shutoff function. We further show that nsp1 interacts with Ras GTPase-activating protein SH3 domain-binding protein 1 (G3BP1) and colocalizes with G3BP1 in SGs under sodium arsenite-induced stress. Finally, we observe that the presence of nsp1 disrupts the maturation of SGs over a long period. Isolation of SG core at different times shows a gradual loss of G3BP1 in the presence of nsp1.
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Affiliation(s)
- Yevgeniy A Gerassimovich
- Natural Sciences and Engineering, University of South Carolina Upstate, Spartanburg, South Carolina, USA
| | | | - Kaitlin M Bridges
- Natural Sciences and Engineering, University of South Carolina Upstate, Spartanburg, South Carolina, USA
| | - Linkel Boateng
- Department of Computer Science and Engineering, University of South Carolina, Columbia, South Carolina, USA
| | - Lauren E Ball
- Department of Cell and Molecular Pharmacology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Homayoun Valafar
- Department of Computer Science and Engineering, University of South Carolina, Columbia, South Carolina, USA
| | - Anita Nag
- Natural Sciences and Engineering, University of South Carolina Upstate, Spartanburg, South Carolina, USA.
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15
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Sidibé H, Dubinski A, Vande Velde C. The multi-functional RNA-binding protein G3BP1 and its potential implication in neurodegenerative disease. J Neurochem 2021; 157:944-962. [PMID: 33349931 PMCID: PMC8248322 DOI: 10.1111/jnc.15280] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/09/2020] [Accepted: 12/11/2020] [Indexed: 12/12/2022]
Abstract
Ras-GTPase-activating protein (GAP)-binding protein 1 (G3BP1) is a multi-functional protein that is best known for its role in the assembly and dynamics of stress granules. Recent studies have highlighted that G3BP1 also has other functions related to RNA metabolism. In the context of disease, G3BP1 has been therapeutically targeted in cancers because its over-expression is correlated with proliferation of cancerous cells and metastasis. However, evidence suggests that G3BP1 is essential for neuronal development and possibly neuronal maintenance. In this review, we will examine the many functions that are carried out by G3BP1 in the context of neurons and speculate how these functions are critical to the progression of neurodegenerative diseases. Additionally, we will highlight the similarities and differences between G3BP1 and the closely related protein G3BP2, which is frequently overlooked. Although G3BP1 and G3BP2 have both been deemed important for stress granule assembly, their roles may differ in other cellular pathways, some of which are specific to the CNS, and presents an opportunity for further exploration.
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Affiliation(s)
- Hadjara Sidibé
- Department of NeurosciencesUniversité de Montréal, and CHUM Research CenterMontréalQCCanada
| | - Alicia Dubinski
- Department of NeurosciencesUniversité de Montréal, and CHUM Research CenterMontréalQCCanada
| | - Christine Vande Velde
- Department of NeurosciencesUniversité de Montréal, and CHUM Research CenterMontréalQCCanada
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16
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Canet-Pons J, Sen NE, Arsović A, Almaguer-Mederos LE, Halbach MV, Key J, Döring C, Kerksiek A, Picchiarelli G, Cassel R, René F, Dieterlé S, Fuchs NV, König R, Dupuis L, Lütjohann D, Gispert S, Auburger G. Atxn2-CAG100-KnockIn mouse spinal cord shows progressive TDP43 pathology associated with cholesterol biosynthesis suppression. Neurobiol Dis 2021; 152:105289. [PMID: 33577922 DOI: 10.1016/j.nbd.2021.105289] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/11/2020] [Accepted: 02/03/2021] [Indexed: 12/12/2022] Open
Abstract
Large polyglutamine expansions in Ataxin-2 (ATXN2) cause multi-system nervous atrophy in Spinocerebellar Ataxia type 2 (SCA2). Intermediate size expansions carry a risk for selective motor neuron degeneration, known as Amyotrophic Lateral Sclerosis (ALS). Conversely, the depletion of ATXN2 prevents disease progression in ALS. Although ATXN2 interacts directly with RNA, and in ALS pathogenesis there is a crucial role of RNA toxicity, the affected functional pathways remain ill defined. Here, we examined an authentic SCA2 mouse model with Atxn2-CAG100-KnockIn for a first definition of molecular mechanisms in spinal cord pathology. Neurophysiology of lower limbs detected sensory neuropathy rather than motor denervation. Triple immunofluorescence demonstrated cytosolic ATXN2 aggregates sequestrating TDP43 and TIA1 from the nucleus. In immunoblots, this was accompanied by elevated CASP3, RIPK1 and PQBP1 abundance. RT-qPCR showed increase of Grn, Tlr7 and Rnaset2 mRNA versus Eif5a2, Dcp2, Uhmk1 and Kif5a decrease. These SCA2 findings overlap well with known ALS features. Similar to other ataxias and dystonias, decreased mRNA levels for Unc80, Tacr1, Gnal, Ano3, Kcna2, Elovl5 and Cdr1 contrasted with Gpnmb increase. Preterminal stage tissue showed strongly activated microglia containing ATXN2 aggregates, with parallel astrogliosis. Global transcriptome profiles from stages of incipient motor deficit versus preterminal age identified molecules with progressive downregulation, where a cluster of cholesterol biosynthesis enzymes including Dhcr24, Msmo1, Idi1 and Hmgcs1 was prominent. Gas chromatography demonstrated a massive loss of crucial cholesterol precursor metabolites. Overall, the ATXN2 protein aggregation process affects diverse subcellular compartments, in particular stress granules, endoplasmic reticulum and receptor tyrosine kinase signaling. These findings identify new targets and potential biomarkers for neuroprotective therapies.
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Affiliation(s)
- Júlia Canet-Pons
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Nesli-Ece Sen
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany; Faculty of Biosciences, Goethe University, 60438 Frankfurt am Main, Germany
| | - Aleksandar Arsović
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Luis-Enrique Almaguer-Mederos
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany; Center for Investigation and Rehabilitation of Hereditary Ataxias (CIRAH), Holguín, Cuba
| | - Melanie V Halbach
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Jana Key
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany; Faculty of Biosciences, Goethe University, 60438 Frankfurt am Main, Germany
| | - Claudia Döring
- Dr. Senckenberg Institute of Pathology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Anja Kerksiek
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, 53127 Bonn, Nordrhein-Westfalen, Germany
| | - Gina Picchiarelli
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Raphaelle Cassel
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Frédérique René
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Stéphane Dieterlé
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Nina V Fuchs
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225 Langen, Germany
| | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225 Langen, Germany
| | - Luc Dupuis
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Dieter Lütjohann
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, 53127 Bonn, Nordrhein-Westfalen, Germany
| | - Suzana Gispert
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Georg Auburger
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany.
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17
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Zheng Y, Zhu G, Tang Y, Yan J, Han S, Yin J, Peng B, He X, Liu W. HDAC6, A Novel Cargo for Autophagic Clearance of Stress Granules, Mediates the Repression of the Type I Interferon Response During Coxsackievirus A16 Infection. Front Microbiol 2020; 11:78. [PMID: 32082291 PMCID: PMC7005486 DOI: 10.3389/fmicb.2020.00078] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 01/15/2020] [Indexed: 01/09/2023] Open
Abstract
Autophagic cargoes ensure selective autophagy for the recognition and removal of various cytosolic aggregated proteins, damaged organelles, or pathogens. Stress granules (SGs), as antiviral immune complexes, serve a positive role in the type I interferon (IFN) response and can be targeted by autophagy (termed granulophagy). However, the cargo of granulophagy remains elusive, and it is still unknown whether granulophagy plays a role in viral infection. Here, we found that histone deacetylase 6 (HDAC6), a component of viral RNA-induced SGs, is a novel granulophagic cargo that is recognized by p62/Sequestosome 1 (SQSTM1) and mediates the degradation of SGs in coxsackievirus A16 (CA16)-infected cells. CA16 viral RNA activated the protein kinase RNA-activated (PKR)/eukaryotic translation initiation factor 2-alpha (eIF2α) pathway to promote SG assembly. The SGs were degraded by CA16-triggered autophagy via the interaction between the ubiquitin-associated (UBA) domain of p62 and the ubiquitin-binding domain (UBD) of HDAC6, which was bridged by a poly-ubiquitin chain. We also found that granulophagy repressed the type I interferon response and facilitated viral replication. These results suggest that HDAC6 might be the first identified granulophagic cargo and granulophagy could be a strategy that viruses apply to repress the antiviral immune response.
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Affiliation(s)
- Yingcheng Zheng
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China.,Shenzhen Research Institute, Wuhan University, Shenzhen, China
| | - Guoguo Zhu
- Department of Emergency, General Hospital of Central Theater Command of People's Liberation Army of China, Wuhan, China
| | - Yinglian Tang
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China.,Shenzhen Research Institute, Wuhan University, Shenzhen, China
| | - Jun Yan
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China.,Shenzhen Research Institute, Wuhan University, Shenzhen, China
| | - Song Han
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Jun Yin
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Biwen Peng
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Xiaohua He
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Wanhong Liu
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China.,Shenzhen Research Institute, Wuhan University, Shenzhen, China
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18
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Gaete-Argel A, Márquez CL, Barriga GP, Soto-Rifo R, Valiente-Echeverría F. Strategies for Success. Viral Infections and Membraneless Organelles. Front Cell Infect Microbiol 2019; 9:336. [PMID: 31681621 PMCID: PMC6797609 DOI: 10.3389/fcimb.2019.00336] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 09/18/2019] [Indexed: 12/12/2022] Open
Abstract
Regulation of RNA homeostasis or “RNAstasis” is a central step in eukaryotic gene expression. From transcription to decay, cellular messenger RNAs (mRNAs) associate with specific proteins in order to regulate their entire cycle, including mRNA localization, translation and degradation, among others. The best characterized of such RNA-protein complexes, today named membraneless organelles, are Stress Granules (SGs) and Processing Bodies (PBs) which are involved in RNA storage and RNA decay/storage, respectively. Given that SGs and PBs are generally associated with repression of gene expression, viruses have evolved different mechanisms to counteract their assembly or to use them in their favor to successfully replicate within the host environment. In this review we summarize the current knowledge about the viral regulation of SGs and PBs, which could be a potential novel target for the development of broad-spectrum antiviral therapies.
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Affiliation(s)
- Aracelly Gaete-Argel
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Chantal L Márquez
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Gonzalo P Barriga
- Emerging Viruses Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Ricardo Soto-Rifo
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Fernando Valiente-Echeverría
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, Santiago, Chile
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19
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Pandey K, Zhong S, Diel DG, Hou Y, Wang Q, Nelson E, Wang X. GTPase-activating protein-binding protein 1 (G3BP1) plays an antiviral role against porcine epidemic diarrhea virus. Vet Microbiol 2019; 236:108392. [PMID: 31500725 PMCID: PMC7117524 DOI: 10.1016/j.vetmic.2019.108392] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/09/2019] [Accepted: 08/18/2019] [Indexed: 12/21/2022]
Abstract
Knockdown of G3BP1 significantly increases PEDV replication. Overexpression of G3BP1 lowers virus replication. Increased pro-inflammatory cytokines in PEDV-infected G3BP1 depleted cells. PEDV induces stress granules in infected Vero cells.
Porcine epidemic diarrhoea virus (PEDV) is a single-stranded, positive-sense RNA virus that belongs to the Coronaviridae. PEDV causes severe diarrhoea and dehydration in nursing piglets, which leads to significant economic losses to the swine industry worldwide. Stress granules (SGs) are sites of mRNA storage that are formed under various stress conditions including viral infections. Increasing evidence suggests that SGs function in antiviral innate immunity of host cells to limit virus replication. Ras-GTPase-activating protein (SH3 domain) binding protein 1 (G3BP1) is a key stress granule-resident protein that nucleates stress granule assembly. Depletion of G3BP1 inhibits SGs formation and overexpression of G3BP1 nucleates SGs assembly. We observed that knockdown of G3BP1 by silencing RNA significantly increased PEDV replication. Overexpression of exogenous G3BP1, on the other hand, lowered virus replication by 100-fold compared to vector control. An increase in the levels of mRNAs of pro-inflammatory cytokines such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) was also observed in PEDV-infected G3BP1 depleted cells compared to PEDV-infected control cells. Taken together, our results suggest that G3BP1 plays an antiviral role and impairs PEDV replication.
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Affiliation(s)
| | | | - Diego G Diel
- Department of Veterinary and Biomedical Sciences, South Dakota State University, Brookings, SD, 57007, USA
| | - Yixuan Hou
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, College of Food, Agriculture and Environmental Sciences, The Ohio State University, Wooster, Ohio, USA
| | - Qiuhong Wang
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, College of Food, Agriculture and Environmental Sciences, The Ohio State University, Wooster, Ohio, USA
| | - Eric Nelson
- Department of Veterinary and Biomedical Sciences, South Dakota State University, Brookings, SD, 57007, USA
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20
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Catanzaro N, Meng XJ. Porcine reproductive and respiratory syndrome virus (PRRSV)-induced stress granules are associated with viral replication complexes and suppression of host translation. Virus Res 2019; 265:47-56. [DOI: 10.1016/j.virusres.2019.02.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 02/20/2019] [Accepted: 02/27/2019] [Indexed: 01/03/2023]
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21
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Medina GN, Segundo FDS, Stenfeldt C, Arzt J, de Los Santos T. The Different Tactics of Foot-and-Mouth Disease Virus to Evade Innate Immunity. Front Microbiol 2018; 9:2644. [PMID: 30483224 PMCID: PMC6241212 DOI: 10.3389/fmicb.2018.02644] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/17/2018] [Indexed: 12/18/2022] Open
Abstract
Like all pathogens, foot-and-mouth disease virus (FMDV) is recognized by the immune system inducing a heightened immune response mainly mediated by type I and type III IFNs. To overcome the strong antiviral response induced by these cytokines, FMDV has evolved many strategies exploiting each region of its small RNA genome. These include: (a) inhibition of IFN induction at the transcriptional and translational level, (b) inhibition of protein trafficking; (c) blockage of specific post-translational modifications in proteins that regulate innate immune signaling; (d) modulation of autophagy; (e) inhibition of stress granule formation; and (f) in vivo modulation of immune cell function. Here, we summarize and discuss FMDV virulence factors and the host immune footprint that characterize infection in cell culture and in the natural hosts.
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Affiliation(s)
- Gisselle N Medina
- Plum Island Animal Disease Center, United States Department of Agriculture, Agricultural Research Service, Orient, NY, United States.,Codagenix Inc., Farmingdale, NY, United States
| | - Fayna Díaz-San Segundo
- Plum Island Animal Disease Center, United States Department of Agriculture, Agricultural Research Service, Orient, NY, United States.,Animal and Plant Health Inspection Service, Plum Island Animal Disease Center, United States Department of Agriculture, Orient, NY, United States
| | - Carolina Stenfeldt
- Plum Island Animal Disease Center, United States Department of Agriculture, Agricultural Research Service, Orient, NY, United States.,Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN, United States
| | - Jonathan Arzt
- Plum Island Animal Disease Center, United States Department of Agriculture, Agricultural Research Service, Orient, NY, United States
| | - Teresa de Los Santos
- Plum Island Animal Disease Center, United States Department of Agriculture, Agricultural Research Service, Orient, NY, United States
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22
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Hill ME, Kumar A, Wells JA, Hobman TC, Julien O, Hardy JA. The Unique Cofactor Region of Zika Virus NS2B-NS3 Protease Facilitates Cleavage of Key Host Proteins. ACS Chem Biol 2018; 13:2398-2405. [PMID: 30080377 DOI: 10.1021/acschembio.8b00508] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Zika virus is an emerging mosquito-borne pathogen capable of severely damaging developing fetuses as well as causing neurological abnormalities in adults. The molecular details of how Zika virus causes pathologies that are unique among the flavivirus family remain poorly understood and have contributed to the lack of Zika antiviral therapies. To elucidate how Zika virus protease (ZVP) affects host cellular pathways and consequent pathologies, we used unbiased N-terminomics to identify 31 human proteins cleaved by the NS2B-NS3 protease. In particular, autophagy-related protein 16-1 (ATG16L1) and eukaryotic translation initiation factor 4 gamma 1 (eIF4G1) are dramatically depleted during Zika virus infection. ATG16L1 and eIF4G1 mediate type-II interferon production and host-cell translation, respectively, likely aiding immune system evasion and driving the Zika life cycle. Intriguingly, the NS2B cofactor region from Zika virus protease is essential for recognition of host cell substrates. Replacing the NS2B region in another flavivirus protease enabled recognition of novel Zika-specific substrates by hybrid proteases, suggesting that the cofactor is the principal determinant in ZVP substrate selection.
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Affiliation(s)
- Maureen E. Hill
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Anil Kumar
- Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - James A. Wells
- Department of Pharmaceutical Chemistry and Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94158, United States
| | - Tom C. Hobman
- Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Olivier Julien
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Jeanne A. Hardy
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, United States
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23
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Zhai X, Wu S, Lin L, Wang T, Zhong X, Chen Y, Xu W, Tong L, Wang Y, Zhao W, Zhong Z. Stress Granule Formation is One of the Early Antiviral Mechanisms for Host Cells Against Coxsackievirus B Infection. Virol Sin 2018; 33:314-322. [PMID: 29959686 DOI: 10.1007/s12250-018-0040-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Accepted: 05/25/2018] [Indexed: 12/11/2022] Open
Abstract
Stress granules (SGs) are intracellular granules formed when cellular translation is blocked and have been reported to be involved in a variety of viral infections. Our previous studies revealed that SGs are involved in the coxsackievirus B (CVB) infection process, but the role of SGs in CVB infection has not been fully explored. In this study, we found that CVB type 3 (CVB3) could induce SG formation in the early phase of infection. Results showed that levels of CVB3 RNA and protein were significantly inhibited during the early stage of CVB3 infection by the elevated formation of SGs, while viral RNA and protein synthesis were significantly promoted when SG formation was blocked. Our findings suggest that SG formation is one of the early antiviral mechanisms for host cells against CVB infection.
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Affiliation(s)
- Xia Zhai
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Shuo Wu
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Lexun Lin
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Tianying Wang
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Xiaoyan Zhong
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Yang Chen
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Weizhen Xu
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Lei Tong
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Yan Wang
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China
| | - Wenran Zhao
- Department of Cell Biology, Harbin Medical University, Harbin, 150081, China.
| | - Zhaohua Zhong
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
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24
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Yang X, Hu Z, Fan S, Zhang Q, Zhong Y, Guo D, Qin Y, Chen M. Picornavirus 2A protease regulates stress granule formation to facilitate viral translation. PLoS Pathog 2018; 14:e1006901. [PMID: 29415027 PMCID: PMC5819834 DOI: 10.1371/journal.ppat.1006901] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 02/20/2018] [Accepted: 01/23/2018] [Indexed: 12/30/2022] Open
Abstract
Stress granules (SGs) contain stalled messenger ribonucleoprotein complexes and are related to the regulation of mRNA translation. Picornavirus infection can interfere with the formation of SGs. However, the detailed molecular mechanisms and functions of picornavirus-mediated regulation of SG formation are not clear. Here, we found that the 2A protease of a picornavirus, EV71, induced atypical stress granule (aSG), but not typical stress granule (tSG), formation via cleavage of eIF4GI. Furthermore, 2A was required and sufficient to inhibit tSGs induced by EV71 infection, sodium arsenite, or heat shock. Infection of 2A protease activity-inactivated recombinant EV71 (EV71-2AC110S) failed to induce aSG formation and only induced tSG formation, which is PKR and eIF2α phosphorylation-dependent. By using a Renilla luciferase mRNA reporter system and RNA fluorescence in situ hybridization assay, we found that EV71-induced aSGs were beneficial to viral translation through sequestering only cellular mRNAs, but not viral mRNAs. In addition, we found that the 2A protease of other picornaviruses such as poliovirus and coxsackievirus also induced aSG formation and blocked tSG formation. Taken together, our results demonstrate that, on one hand, EV71 infection induces tSG formation via the PKR-eIF2α pathway, and on the other hand, 2A, but not 3C, blocks tSG formation. Instead, 2A induces aSG formation by cleaving eIF4GI to sequester cellular mRNA but release viral mRNA, thereby facilitating viral translation. When cellular translation initiation is stalled, translation initiation complexes aggregate in cytoplasm. We call these aggregations stress granules (SGs), and they can be marked by components such as TIA-1. SGs are always considered to be antiviral structures during viral infection, but viruses also regulate SG formation to facilitate their survival. Here, we show that the 2A protease of EV71 induced TIA-1 foci formation, and we analyzed these TIA-1 foci and found that they were different from typical stress granules (tSGs); thus, we named them atypical stress granules (aSGs). 2A alone could block tSG formation, and we found that protease activity of 2A was required for aSG induction and tSG blockage, but functioned in different ways. When the protease activity of 2A in EV71 was blocked (EV71-2AC110S), the tSGs but not aSGs appeared in infected cells. These tSGs contained cellular and viral mRNAs and translation initiation factors to inhibit viral translation, but aSGs contained only cellular mRNAs to promote viral translation. We propose a model revealing that EV71 escapes cellular antiviral response by manipulating SG formation: 2A transforms the overall translation shutdown system to a selective virally beneficial system by switching from tSGs to aSGs.
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Affiliation(s)
- Xiaodan Yang
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
| | - Zhulong Hu
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
| | - Shanshan Fan
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
| | - Qiang Zhang
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
| | - Yi Zhong
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
| | - Dong Guo
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
| | - Yali Qin
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
| | - Mingzhou Chen
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan, China
- * E-mail:
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Uversky VN. The roles of intrinsic disorder-based liquid-liquid phase transitions in the "Dr. Jekyll-Mr. Hyde" behavior of proteins involved in amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Autophagy 2017; 13:2115-2162. [PMID: 28980860 DOI: 10.1080/15548627.2017.1384889] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Pathological developments leading to amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are associated with misbehavior of several key proteins, such as SOD1 (superoxide dismutase 1), TARDBP/TDP-43, FUS, C9orf72, and dipeptide repeat proteins generated as a result of the translation of the intronic hexanucleotide expansions in the C9orf72 gene, PFN1 (profilin 1), GLE1 (GLE1, RNA export mediator), PURA (purine rich element binding protein A), FLCN (folliculin), RBM45 (RNA binding motif protein 45), SS18L1/CREST, HNRNPA1 (heterogeneous nuclear ribonucleoprotein A1), HNRNPA2B1 (heterogeneous nuclear ribonucleoprotein A2/B1), ATXN2 (ataxin 2), MAPT (microtubule associated protein tau), and TIA1 (TIA1 cytotoxic granule associated RNA binding protein). Although these proteins are structurally and functionally different and have rather different pathological functions, they all possess some levels of intrinsic disorder and are either directly engaged in or are at least related to the physiological liquid-liquid phase transitions (LLPTs) leading to the formation of various proteinaceous membrane-less organelles (PMLOs), both normal and pathological. This review describes the normal and pathological functions of these ALS- and FTLD-related proteins, describes their major structural properties, glances at their intrinsic disorder status, and analyzes the involvement of these proteins in the formation of normal and pathological PMLOs, with the ultimate goal of better understanding the roles of LLPTs and intrinsic disorder in the "Dr. Jekyll-Mr. Hyde" behavior of those proteins.
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Affiliation(s)
- Vladimir N Uversky
- a Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute , Morsani College of Medicine , University of South Florida , Tampa , FL , USA.,b Institute for Biological Instrumentation of the Russian Academy of Sciences , Pushchino, Moscow region , Russia
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Zika Virus Hijacks Stress Granule Proteins and Modulates the Host Stress Response. J Virol 2017; 91:JVI.00474-17. [PMID: 28592527 DOI: 10.1128/jvi.00474-17] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 05/24/2017] [Indexed: 11/20/2022] Open
Abstract
Zika virus (ZIKV), a member of the Flaviviridae family, has recently emerged as an important human pathogen with increasing economic and health impact worldwide. Because of its teratogenic nature and association with the serious neurological condition Guillain-Barré syndrome, a tremendous amount of effort has focused on understanding ZIKV pathogenesis. To gain further insights into ZIKV interaction with host cells, we investigated how this pathogen affects stress response pathways. While ZIKV infection induces stress signaling that leads to phosphorylation of eIF2α and cellular translational arrest, stress granule (SG) formation was inhibited. Further analysis revealed that the viral proteins NS3 and NS4A are linked to translational repression, whereas expression of the capsid protein, NS3/NS2B-3, and NS4A interfered with SG formation. Some, but not all, flavivirus capsid proteins also blocked SG assembly, indicating differential interactions between flaviviruses and SG biogenesis pathways. Depletion of the SG components G3BP1, TIAR, and Caprin-1, but not TIA-1, reduced ZIKV replication. Both G3BP1 and Caprin-1 formed complexes with capsid, whereas viral genomic RNA stably interacted with G3BP1 during ZIKV infection. Taken together, these results are consistent with a scenario in which ZIKV uses multiple viral components to hijack key SG proteins to benefit viral replication.IMPORTANCE There is a pressing need to understand ZIKV pathogenesis in order to advance the development of vaccines and therapeutics. The cellular stress response constitutes one of the first lines of defense against viral infection; therefore, understanding how ZIKV evades this antiviral system will provide key insights into ZIKV biology and potentially pathogenesis. Here, we show that ZIKV induces the stress response through activation of the UPR (unfolded protein response) and PKR (protein kinase R), leading to host translational arrest, a process likely mediated by the viral proteins NS3 and NS4A. Despite the activation of translational shutoff, formation of SG is strongly inhibited by the virus. Specifically, ZIKV hijacks the core SG proteins G3BP1, TIAR, and Caprin-1 to facilitate viral replication, resulting in impaired SG assembly. This process is potentially facilitated by the interactions of the viral RNA with G3BP1 as well as the viral capsid protein with G3BP1 and Caprin-1. Interestingly, expression of capsid proteins from several other flaviviruses also inhibited SG formation. Taken together, the present study provides novel insights into how ZIKV modulates cellular stress response pathways during replication.
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Mäkinen K, Lõhmus A, Pollari M. Plant RNA Regulatory Network and RNA Granules in Virus Infection. FRONTIERS IN PLANT SCIENCE 2017; 8:2093. [PMID: 29312371 PMCID: PMC5732267 DOI: 10.3389/fpls.2017.02093] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 11/24/2017] [Indexed: 05/18/2023]
Abstract
Regulation of post-transcriptional gene expression on mRNA level in eukaryotic cells includes translocation, translation, translational repression, storage, mRNA decay, RNA silencing, and nonsense-mediated decay. These processes are associated with various RNA-binding proteins and cytoplasmic ribonucleoprotein complexes many of which are conserved across eukaryotes. Microscopically visible aggregations formed by ribonucleoprotein complexes are termed RNA granules. Stress granules where the translationally inactive mRNAs are stored and processing bodies where mRNA decay may occur present the most studied RNA granule types. Diverse RNP-granules are increasingly being assigned important roles in viral infections. Although the majority of the molecular level studies on the role of RNA granules in viral translation and replication have been conducted in mammalian systems, some studies link also plant virus infection to RNA granules. An increasing body of evidence indicates that plant viruses require components of stress granules and processing bodies for their replication and translation, but how extensively the cellular mRNA regulatory network is utilized by plant viruses has remained largely enigmatic. Antiviral RNA silencing, which is an important regulator of viral RNA stability and expression in plants, is commonly counteracted by viral suppressors of RNA silencing. Some of the RNA silencing suppressors localize to cellular RNA granules and have been proposed to carry out their suppression functions there. Moreover, plant nucleotide-binding leucine-rich repeat protein-mediated virus resistance has been linked to enhanced processing body formation and translational repression of viral RNA. Many interesting questions relate to how the pathways of antiviral RNA silencing leading to viral RNA degradation and/or repression of translation, suppression of RNA silencing and viral RNA translation converge in plants and how different RNA granules and their individual components contribute to these processes. In this review we discuss the roles of cellular RNA regulatory mechanisms and RNA granules in plant virus infection in the light of current knowledge and compare the findings to those made in animal virus studies.
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Le Sage V, Cinti A, McCarthy S, Amorim R, Rao S, Daino GL, Tramontano E, Branch DR, Mouland AJ. Ebola virus VP35 blocks stress granule assembly. Virology 2016; 502:73-83. [PMID: 28013103 DOI: 10.1016/j.virol.2016.12.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 12/08/2016] [Accepted: 12/12/2016] [Indexed: 10/20/2022]
Abstract
Stress granules (SGs) are dynamic cytoplasmic aggregates of translationally silenced mRNAs that assemble in response to environmental stress. SGs appear to play an important role in antiviral innate immunity and many viruses have evolved to block or subvert SGs components for their own benefit. Here, we demonstrate that intracellular Ebola virus (EBOV) replication and transcription-competent virus like particles (trVLP) infection does not lead to SG assembly but leads to a blockade to Arsenite-induced SG assembly. Moreover we show that EBOV VP35 represses the assembly of canonical and non-canonical SGs induced by a variety of pharmacological stresses. This SG blockade requires, at least in part, the C-terminal domain of VP35. Furthermore, results from our co-immunoprecipitation studies indicate that VP35 interacts with multiple SG components, including G3BP1, eIF3 and eEF2 through a stress- and RNA-independent mechanism. These data suggest a novel function for EBOV VP35 in the repression of SG assembly.
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Affiliation(s)
- Valerie Le Sage
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, Québec, Canada H3T 1E2
| | - Alessandro Cinti
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, Québec, Canada H3T 1E2; Department of Medicine, McGill University, Montréal, Québec, Canada H3A 0G4
| | - Stephen McCarthy
- Centre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Ontario, Toronto, Canada
| | - Raquel Amorim
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, Québec, Canada H3T 1E2; Department of Medicine, McGill University, Montréal, Québec, Canada H3A 0G4
| | - Shringar Rao
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, Québec, Canada H3T 1E2; Department of Microbiology and Immunology, McGill University, Montréal, Québec, Canada H3A 0G4
| | - Gian Luca Daino
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, SS 554, 09042 Monserrato, Cagliari, Italy
| | - Enzo Tramontano
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, SS 554, 09042 Monserrato, Cagliari, Italy
| | - Donald R Branch
- Centre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Ontario, Toronto, Canada
| | - Andrew J Mouland
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, Québec, Canada H3T 1E2; Department of Medicine, McGill University, Montréal, Québec, Canada H3A 0G4; Department of Microbiology and Immunology, McGill University, Montréal, Québec, Canada H3A 0G4.
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Ebola Virus Does Not Induce Stress Granule Formation during Infection and Sequesters Stress Granule Proteins within Viral Inclusions. J Virol 2016; 90:7268-7284. [PMID: 27252530 DOI: 10.1128/jvi.00459-16] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/25/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED A hallmark of Ebola virus (EBOV) infection is the formation of viral inclusions in the cytoplasm of infected cells. These viral inclusions contain the EBOV nucleocapsids and are sites of viral replication and nucleocapsid maturation. Although there is growing evidence that viral inclusions create a protected environment that fosters EBOV replication, little is known about their role in the host response to infection. The cellular stress response is an effective antiviral strategy that leads to stress granule (SG) formation and translational arrest mediated by the phosphorylation of a translation initiation factor, the α subunit of eukaryotic initiation factor 2 (eIF2α). Here, we show that selected SG proteins are sequestered within EBOV inclusions, where they form distinct granules that colocalize with viral RNA. These inclusion-bound (IB) granules are functionally and structurally different from canonical SGs. Formation of IB granules does not indicate translational arrest in the infected cells. We further show that EBOV does not induce formation of canonical SGs or eIF2α phosphorylation at any time postinfection but is unable to fully inhibit SG formation induced by different exogenous stressors, including sodium arsenite, heat, and hippuristanol. Despite the sequestration of SG marker proteins into IB granules, canonical SGs are unable to form within inclusions, which we propose might be mediated by a novel function of VP35, which disrupts SG formation. This function is independent of VP35's RNA binding activity. Further studies aim to reveal the mechanism for SG protein sequestration and precise function within inclusions. IMPORTANCE Although progress has been made developing antiviral therapeutics and vaccines against the highly pathogenic Ebola virus (EBOV), the cellular mechanisms involved in EBOV infection are still largely unknown. To better understand these intracellular events, we investigated the cellular stress response, an antiviral pathway manipulated by many viruses. We show that EBOV does not induce formation of stress granules (SGs) in infected cells and is therefore unrestricted by their concomitant translational arrest. We identified SG proteins sequestered within viral inclusions, which did not impair protein translation. We further show that EBOV is unable to block SG formation triggered by exogenous stress early in infection. These findings provide insight into potential targets of therapeutic intervention. Additionally, we identified a novel function of the interferon antagonist VP35, which is able to disrupt SG formation.
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Poblete-Durán N, Prades-Pérez Y, Vera-Otarola J, Soto-Rifo R, Valiente-Echeverría F. Who Regulates Whom? An Overview of RNA Granules and Viral Infections. Viruses 2016; 8:v8070180. [PMID: 27367717 PMCID: PMC4974515 DOI: 10.3390/v8070180] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/10/2016] [Accepted: 06/21/2016] [Indexed: 12/22/2022] Open
Abstract
After viral infection, host cells respond by mounting an anti-viral stress response in order to create a hostile atmosphere for viral replication, leading to the shut-off of mRNA translation (protein synthesis) and the assembly of RNA granules. Two of these RNA granules have been well characterized in yeast and mammalian cells, stress granules (SGs), which are translationally silent sites of RNA triage and processing bodies (PBs), which are involved in mRNA degradation. This review discusses the role of these RNA granules in the evasion of anti-viral stress responses through virus-induced remodeling of cellular ribonucleoproteins (RNPs).
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Affiliation(s)
- Natalia Poblete-Durán
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Independencia 1027, Santiago, 8389100, Chile.
| | - Yara Prades-Pérez
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Independencia 1027, Santiago, 8389100, Chile.
| | - Jorge Vera-Otarola
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Centro de Investigaciones Médicas, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago 8330024, Chile.
| | - Ricardo Soto-Rifo
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Independencia 1027, Santiago, 8389100, Chile.
| | - Fernando Valiente-Echeverría
- Molecular and Cellular Virology Laboratory, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Independencia 1027, Santiago, 8389100, Chile.
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31
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Liem J, Liu J. Stress Beyond Translation: Poxviruses and More. Viruses 2016; 8:v8060169. [PMID: 27314378 PMCID: PMC4926189 DOI: 10.3390/v8060169] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/24/2016] [Accepted: 06/08/2016] [Indexed: 02/06/2023] Open
Abstract
Poxviruses are large double-stranded DNA viruses that form viral factories in the cytoplasm of host cells. These viruses encode their own transcription machinery, but rely on host translation for protein synthesis. Thus, poxviruses have to cope with and, in most cases, reprogram host translation regulation. Granule structures, called antiviral granules (AVGs), have been observed surrounding poxvirus viral factories. AVG formation is associated with abortive poxvirus infection, and AVGs contain proteins that are typically found in stress granules (SGs). With certain mutant poxviruses lack of immunoregulatory factor(s), we can specifically examine the mechanisms that drive the formation of these structures. In fact, cytoplasmic macromolecular complexes form during many viral infections and contain sensing molecules that can help reprogram transcription. More importantly, the similarity between AVGs and cytoplasmic structures formed during RNA and DNA sensing events prompts us to reconsider the cause and consequence of these AVGs. In this review, we first summarize recent findings regarding how poxvirus manipulates host translation. Next, we compare and contrast SGs and AVGs. Finally, we review recent findings regarding RNA- and especially DNA-sensing bodies observed during viral infection.
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Affiliation(s)
- Jason Liem
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas.
| | - Jia Liu
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Inflammatory Responses, University of Arkansas for Medical Sciences, Little Rock, Arkansas.
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Zhu Y, Wang B, Huang H, Zhao Z. Enterovirus 71 induces anti-viral stress granule-like structures in RD cells. Biochem Biophys Res Commun 2016; 476:212-217. [PMID: 27216457 PMCID: PMC7124267 DOI: 10.1016/j.bbrc.2016.05.094] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 05/19/2016] [Indexed: 01/20/2023]
Abstract
Stress granules (SGs) are dynamic cytoplasmic granules formed in response to a variety of stresses, including viral infection. Several viruses can modulate the formation of SG with different effects, but the relationship between SG formation and EV71 infection is poorly understood. In this study, we report that EV71 inhibits canonical SGs formation in infected cells and induces the formation of novel RNA granules that were distinguished from canonical SGs in composition and morphology, which we termed ‘SG like structures’. Our results also demonstrated that EV71 triggered formation of SG-like structures is dependent on PKR and eIF2α phosphorylation and requires ongoing cellular mRNA synthesis. Finally, we found that SG-like structures are antiviral RNA granules that promote cellular apoptosis and suppress EV71 propagation. Taken together, our findings explain the formation mechanism of SG-like structures induced by EV71 and shed light on virus-host interaction and molecular mechanism underlying EV71 pathogenesis. EV71 infection inhibits canonical SG formation and induces formation of novel SG-like structures. SG-like structures are distinguished from canonical SGs in composition and morphology. EV71 induces SG-like structures are antiviral RNA granules which promote cellular apoptosis and suppress EV71 propagation.
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Affiliation(s)
- Yuanmei Zhu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Bei Wang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - He Huang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Zhendong Zhao
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China.
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Abstract
T-cell intracellular antigen 1 (TIA1) and TIA1-related/like protein (TIAR/TIAL1) are 2 proteins discovered in 1991 as components of cytotoxic T lymphocyte granules. They act in the nucleus as regulators of transcription and pre-mRNA splicing. In the cytoplasm, TIA1 and TIAR regulate and/or modulate the location, stability and/or translation of mRNAs. As knowledge of the different genes regulated by these proteins and the cellular/biological programs in which they are involved increases, it is evident that these antigens are key players in human physiology and pathology. This review will discuss the latest developments in the field, with physiopathological relevance, that point to novel roles for these regulators in the molecular and cell biology of higher eukaryotes.
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Affiliation(s)
- Carmen Sánchez-Jiménez
- a Centro de Biología Molecular Severo Ochoa; Consejo Superior de Investigaciones Científicas; Universidad Autónoma de Madrid (CSIC/UAM); C/Nicolás Cabrera 1 ; Madrid , Spain
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Lloyd RE. Enterovirus Control of Translation and RNA Granule Stress Responses. Viruses 2016; 8:93. [PMID: 27043612 PMCID: PMC4848588 DOI: 10.3390/v8040093] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 03/26/2016] [Accepted: 03/29/2016] [Indexed: 12/24/2022] Open
Abstract
Enteroviruses such as poliovirus (PV) and coxsackievirus B3 (CVB3) have evolved several parallel strategies to regulate cellular gene expression and stress responses to ensure efficient expression of the viral genome. Enteroviruses utilize their encoded proteinases to take over the cellular translation apparatus and direct ribosomes to viral mRNAs. In addition, viral proteinases are used to control and repress the two main types of cytoplasmic RNA granules, stress granules (SGs) and processing bodies (P-bodies, PBs), which are stress-responsive dynamic structures involved in repression of gene expression. This review discusses these processes and the current understanding of the underlying mechanisms with respect to enterovirus infections. In addition, the review discusses accumulating data suggesting linkage exists between RNA granule formation and innate immune sensing and activation.
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Affiliation(s)
- Richard E Lloyd
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
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Abstract
RNA granules are dynamic cellular structures essential for proper gene expression and homeostasis. The two principal types of cytoplasmic RNA granules are stress granules, which contain stalled translation initiation complexes, and processing bodies (P bodies), which concentrate factors involved in mRNA degradation. RNA granules are associated with gene silencing of transcripts; thus, viruses repress RNA granule functions to favor replication. This article discusses the breadth of viral interactions with cytoplasmic RNA granules, focusing on mechanisms that modulate the functions of RNA granules and that typically promote viral replication. Currently, mechanisms for virus manipulation of RNA granules can be loosely grouped into three nonexclusive categories: (a) cleavage of key RNA granule factors, (b) regulation of PKR activation, and (c) co-opting of RNA granule factors for new roles in viral replication. Viral modulation of RNA granules supports productive infection by inhibiting their gene-silencing functions and counteracting their role in linking stress sensing with innate immune activation.
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Affiliation(s)
- Wei-Chih Tsai
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030;
| | - Richard E Lloyd
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030;
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Abstract
Unr (upstream of N-ras) is a post-transcriptional regulator of gene expression, essential for mammalian development and mutated in many human cancers. The expression of unr is itself regulated at many levels; transcription of unr, which also affects expression of the downstream N-ras gene, is tissue and developmental stage-dependent and is repressed by c-Myc and Max (Myc associated factor X). Alternative splicing gives rise to six transcript variants, which include three different 5′-UTRs. The transcripts are further diversified by the use of three alternative polyadenylation signals, which governs whether AU-rich instability elements are present in the 3′-UTR or not. Translation of at least some unr transcripts can occur by internal initiation and is regulated in a cell-cycle-dependent manner; binding of PTB (polypyrimidine tract-binding protein) and Unr to the 5′-UTR inhibits translation, but these are displaced by heterogeneous nuclear ribonucleoproteins C1/C2 (hnRNPC1/C2) during mitosis to stimulate translation. Finally, Unr is post-translationally modified by phosphorylation and lysine acetylation, although it is not yet known how these modifications affect Unr activity.
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Dougherty JD, Tsai WC, Lloyd RE. Multiple Poliovirus Proteins Repress Cytoplasmic RNA Granules. Viruses 2015; 7:6127-40. [PMID: 26610553 PMCID: PMC4690851 DOI: 10.3390/v7122922] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 01/05/2023] Open
Abstract
We have previously shown that poliovirus (PV) infection induces stress granule (SG) formation early in infection and then inhibits the formation of SG and disperses processing bodies (PBs) by the mid-phase of infection. Loss of SG was linked to cleavage of G3BP1 by viral 3C proteinase (3Cpro), however dispersal of PBs was not strongly linked to cleavage of specific factors by viral proteinases, suggesting other viral proteins may play roles in inhibition of SG or PB formation. Here we have screened all viral proteins for roles in inducing or inhibiting the formation of RNA granules by creating fusions with mCherry and expressing them individually in cells. Expression of viral proteins separately revealed that the capsid region P1, 2Apro, 3A, 3Cpro, the protease precursor 3CD and 3D polymerase all affect RNA granules to varying extents, whereas 2BC does not. 2Apro, which cleaves eIF4GI, induced SGs as expected, and entered novel foci containing the SG nucleating protein G3BP1. Of the two forms of G3BP, only G3BP1 is cleaved by a virus proteinase, 3Cpro, whereas G3BP2 is not cleaved by 3Cpro or 2Apro. Surprisingly, 3CD, which contains proteinase activity, differentially repressed PBs but not SGs. Further, both 2Apro and 3Cpro expression dispersed PBs, however molecular targets were different since PB dispersal due to 2Apro and heat shock protein (Hsp)90 inhibition but not 3Cpro, could be rescued by application of oxidative stress to cells. The data indicate that PV repression of SGs and PBs is multifactorial, though protease function is dominant.
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Affiliation(s)
- Jonathan D Dougherty
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Wei-Chih Tsai
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Richard E Lloyd
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
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TIA-1 and TIAR interact with 5′-UTR of enterovirus 71 genome and facilitate viral replication. Biochem Biophys Res Commun 2015; 466:254-9. [DOI: 10.1016/j.bbrc.2015.09.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/04/2015] [Indexed: 12/17/2022]
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Song L, Wang H, Wang T, Lu L. Sequestration of RNA by grass carp Ctenopharyngodon idella TIA1 is associated with its positive role in facilitating grass carp reovirus infection. FISH & SHELLFISH IMMUNOLOGY 2015; 46:442-448. [PMID: 26208752 PMCID: PMC7173117 DOI: 10.1016/j.fsi.2015.07.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 07/10/2015] [Accepted: 07/19/2015] [Indexed: 05/27/2023]
Abstract
Previous report demonstrated that grass carp reovirus (GCRV) infection resulted in unlinking cellular stress granule formation from aggregation of grass carp Ctenopharyngodon idella TIA1 (CiTIA1). Here, we provided evidence to show that CiTIA1 bound to synthesized ssRNA and dsRNA in vitro. Both GST-pull down assay and RNA immunoprecipitation analysis confirmed the association between GCRV-specific RNA and GST-tagged CiTIA1 in C. idella kidney (CIK) cells. Furthermore, CiTIA1 was shown to protect dsRNA of virus-origin from degradation in CIK cells through Northern blot analysis. Finally, transient overexpression of CiTIA1 enhanced the replication efficiency of GCRV in CIK cells. Taken together, our results suggested that cellular CiTIA1 might facilitate GCRV replication through sequestrating and protecting viral RNA from degradation.
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Affiliation(s)
- Lang Song
- MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, PR China
| | - Hao Wang
- MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, PR China
| | - Tu Wang
- MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, PR China
| | - Liqun Lu
- MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, PR China.
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Yoshida A, Kawabata R, Honda T, Tomonaga K, Sakaguchi T, Irie T. IFN-β-inducing, unusual viral RNA species produced by paramyxovirus infection accumulated into distinct cytoplasmic structures in an RNA-type-dependent manner. Front Microbiol 2015; 6:804. [PMID: 26300870 PMCID: PMC4523817 DOI: 10.3389/fmicb.2015.00804] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 07/22/2015] [Indexed: 12/22/2022] Open
Abstract
The interferon (IFN) system is one of the most important defensive responses of mammals against viruses, and is rapidly evoked when the pathogen-associated molecular patterns (PAMPs) of viruses are sensed. Non-self, virus-derived RNA species have been identified as the PAMPs of RNA viruses. In the present study, we compared different types of IFN-β-inducing and -non-inducing viruses in the context of Sendai virus infection. We found that some types of unusual viral RNA species were produced by infections with IFN-β-inducing viruses and accumulated into distinct cytoplasmic structures in an RNA-type-dependent manner. One of these structures was similar to the so-called antiviral stress granules (avSGs) formed by an infection with IFN-inducing viruses whose C proteins were knocked-out or mutated. Non-encapsidated, unusual viral RNA harboring the 5'-terminal region of the viral genome as well as RIG-I and typical SG markers accumulated in these granules. Another was a non-SG-like inclusion formed by an infection with the Cantell strain; a copyback-type DI genome, but not an authentic viral genome, specifically accumulated in the inclusion, whereas RIG-I and SG markers did not. The induction of IFN-β was closely associated with the production of these unusual RNAs as well as the formation of the cytoplasmic structures.
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Affiliation(s)
- Asuka Yoshida
- Department of Virology, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima Japan
| | - Ryoko Kawabata
- Department of Virology, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima Japan
| | - Tomoyuki Honda
- Department of Viral Oncology, Institute for Virus Research, Kyoto University, Kyoto Japan
| | - Keizo Tomonaga
- Department of Viral Oncology, Institute for Virus Research, Kyoto University, Kyoto Japan
| | - Takemasa Sakaguchi
- Department of Virology, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima Japan
| | - Takashi Irie
- Department of Virology, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima Japan
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Xu D, Song L, Wang H, Xu X, Wang T, Lu L. Proteomic analysis of cellular protein expression profiles in response to grass carp reovirus infection. FISH & SHELLFISH IMMUNOLOGY 2015; 44:515-524. [PMID: 25783000 DOI: 10.1016/j.fsi.2015.03.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 03/04/2015] [Accepted: 03/06/2015] [Indexed: 06/04/2023]
Abstract
Grass carp (Ctenopharyngodon idella) hemorrhagic disease, caused by grass carp reovirus (GCRV), is emerging as a serious problem in grass carp aquaculture. To better understand the molecular responses to GCRV infection, two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization tandem mass spectroscopy were performed to investigate altered proteins in C. idella kidney (CIK) cells. Differentially expressed proteins in mock infected CIK cells and GCRV-infected CIK cells were compared. Twenty-three differentially expressed spots were identified (22 upregulated spots and 1 downregulated spot), which included cytoskeleton proteins, macromolecular biosynthesis-associated proteins, stress response proteins, signal transduction proteins, energy metabolism-associated proteins and ubiquitin proteasome pathway-associated proteins. Moreover, 10 of the corresponding genes of the differentially expressed proteins were quantified by real-time reverse transcription polymerase chain reaction to examine their transcriptional profiles. The T cell internal antigen 1 (TIA1) and Ras-GTPase-activating SH3-domain-binding protein1 (G3BP1) of the cellular stress granule pathway from grass carp C. idella (designated as CiTIA1 and CiG3BP1) were upregulated and downregulated during GCRV infection, respectively. The full-length cDNA of CiTIA1 was 2753 bp, with an open reading frame (ORF) of 1155bp, which encodes a putative 385-amino acid protein. The 2271 bp full-length cDNA of CiG3BP1 comprised an ORF of 1455 bp that encodes a putative 485-amino acid protein. Phylogenetic analysis revealed that the complete ORFs of CiTIA1 and CiG3BP1 were very similar to zebrafish and well-characterized mammalian homologs. The expressions of the cellular proteins CiTIA1 and CiG3BP1 in response to GCRV were validated by western blotting, which indicated that the GCRV should unlink TIA1 aggregation and stress granule formation. This study provides useful information on the proteomic and cellular stress granule pathway's responses to GCRV infection, which adds to our understanding of viral pathogenesis.
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Affiliation(s)
- Dan Xu
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, Shanghai 201306, PR China
| | - Lang Song
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, Shanghai 201306, PR China
| | - Hao Wang
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, Shanghai 201306, PR China
| | - Xiaoyan Xu
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, Shanghai 201306, PR China
| | - Tu Wang
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, Shanghai 201306, PR China
| | - Liqun Lu
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, Shanghai 201306, PR China.
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Panas MD, Kedersha N, McInerney GM. Methods for the characterization of stress granules in virus infected cells. Methods 2015; 90:57-64. [PMID: 25896634 PMCID: PMC7128402 DOI: 10.1016/j.ymeth.2015.04.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 12/25/2022] Open
Abstract
Stress granules are induced as a cellular defence against virus infection. We discuss methods for the detection of viral and cellular proteins and RNA in SGs. In addition, we describe a surrogate in vitro assay for SG formation.
Stress granules are induced in many different viral infections, and in turn are inhibited by the expression of viral proteins or RNAs. It is therefore evident that these bodies are not compatible with efficient viral replication, but the mechanism by which they act to restrict viral gene expression or genome replication is not yet understood. This article discusses a number of methods that can be employed to gain a more complete understanding of the relationship between cellular SGs and viral RNA and protein synthesis in cells infected with diverse viruses.
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Affiliation(s)
- Marc D Panas
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Nancy Kedersha
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA
| | - Gerald M McInerney
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
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Kempf BJ, Barton DJ. Picornavirus RNA polyadenylation by 3D(pol), the viral RNA-dependent RNA polymerase. Virus Res 2015; 206:3-11. [PMID: 25559071 PMCID: PMC4801031 DOI: 10.1016/j.virusres.2014.12.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 12/15/2014] [Accepted: 12/24/2014] [Indexed: 11/06/2022]
Abstract
Picornaviral RdRPs are responsible for the polyadenylation of viral RNA. Reiterative transcription mechanisms occur during replication of poly(A) tails. Conserved RdRP structures influence the size of poly(A) tails. Common features of picornavirus RdRPs and telomerase reverse transcriptase. Poly(A) tails are a telomere of picornavirus RNA genomes.
Poly(A) tails are functionally important features of all picornavirus RNA genomes. Some viruses have genomes with relatively short poly(A) tails (encephalomyocarditis virus) whereas others have genomes with longer poly(A) tails (polioviruses and rhinoviruses). Here we review the polyadenylation of picornavirus RNA as it relates to the structure and function of 3Dpol. Poliovirus 3Dpol uses template-dependent reiterative transcription mechanisms as it replicates the poly(A) tails of viral RNA (Steil et al., 2010). These mechanisms are analogous to those involved in the polyadenylation of vesicular stomatitis virus and influenza virus mRNAs. 3Dpol residues intimately associated with viral RNA templates and products regulate the size of poly(A) tails in viral RNA (Kempf et al., 2013). Consistent with their ancient evolutionary origins, picornavirus 3Dpol and telomerase reverse transcriptase (TERT) share structural and functional features. Structurally, both 3Dpol and TERT assume a “right-hand” conformation with thumb, palm and fingers domains encircling templates and products. Functionally, both 3Dpol and TERT use template-dependent reiterative transcription mechanisms to synthesize repetitive sequences: poly(A) tails in the case of picornavirus RNA genomes and DNA telomeres in the case of eukaryotic chromosomes. Thus, picornaviruses and their eukaryotic hosts (humans and animals) maintain the 3′ ends of their respective genomes via evolutionarily related mechanisms.
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Affiliation(s)
- Brian J Kempf
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, United States
| | - David J Barton
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, United States.
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Wu S, Wang Y, Lin L, Si X, Wang T, Zhong X, Tong L, Luan Y, Chen Y, Li X, Zhang F, Zhao W, Zhong Z. Protease 2A induces stress granule formation during coxsackievirus B3 and enterovirus 71 infections. Virol J 2014; 11:192. [PMID: 25410318 PMCID: PMC4247557 DOI: 10.1186/s12985-014-0192-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 10/26/2014] [Indexed: 02/02/2023] Open
Abstract
Background Stress granules (SGs) are granular aggregates in the cytoplasm that are formed under a variety of stress situations including viral infection. Previous studies indicate that poliovirus, a member of Picornaviridae, can induce SG formation. However, the exact mechanism by which the picornaviruses induce SG formation is unknown. Method The localization of SG markers in cells infected with coxsackievirus B3 (CVB3) or enterovirus 71 (EV71) and in cells expressing each viral protein was determined via immunofluorescence assays or plasmid transfection. Eight plasmids expressing mutants of the 2A protease (2Apro) of CVB3 were generated using a site-directed mutagenesis strategy. The cleavage efficiencies of eIF4G by CVB3 2Apro and its mutants were determined via western blotting assays. Results In this study, we found that CVB3 infection induced SG formation, as evidenced by the co-localization of some accepted SG markers in viral infection-induced granules. Furthermore, we identified that 2Apro of CVB3 was the key viral component that triggered SG formation. A 2Apro mutant with the G122E mutation, which exhibited very low cleavage efficiency toward eIF4G, significantly attenuated its capacity for SG induction, indicating that the protease activity was required for 2Apro to initiate SG formation. Finally, we observed that SGs also formed in EV71-infected cells. Expression of EV71 2Apro alone was also sufficient to cause SG formation. Conclusion Both CVB3 and EV71 infections can induce SG formation, and 2Apro plays a crucial role in the induction of SG formation during these infections. This finding may help us to better understand how picornaviruses initiate the SG response. Electronic supplementary material The online version of this article (doi:10.1186/s12985-014-0192-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shuo Wu
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Yan Wang
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Lexun Lin
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Xiaoning Si
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Tianying Wang
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Xiaoyan Zhong
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Lei Tong
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Ying Luan
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Yang Chen
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Xiaoyu Li
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Florida-Jacksonville, Jacksonville, FL, 32206, USA.
| | - Fengmin Zhang
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
| | - Wenran Zhao
- Department of Cell Biology, Harbin Medical University, Harbin, 150081, China.
| | - Zhaohua Zhong
- Department of Microbiology, Harbin Medical University, Harbin, 150081, China.
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Wu S, Lin L, Zhao W, Li X, Wang Y, Si X, Wang T, Wu H, Zhai X, Zhong X, Gao S, Tong L, Xu Z, Zhong Z. AUF1 is recruited to the stress granules induced by coxsackievirus B3. Virus Res 2014; 192:52-61. [PMID: 25148713 DOI: 10.1016/j.virusres.2014.08.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 08/05/2014] [Accepted: 08/11/2014] [Indexed: 11/18/2022]
Abstract
Stress granules (SGs) are cytoplasmic granules that are formed in cells when stress occurs. In this study, we found that SGs formed in cells infected with coxsackievirus B3 (CVB3), evidenced with the co-localization of some accepted SG markers in the viral infection-induced granules. We further discovered that adenosine-uridine (AU)-rich element RNA binding factor 1 (AUF1), which can bind to mRNAs and regulate their translation, was recruited to the SGs in response to high dose of CVB3 by detecting the co-localization of AUF1 with SG markers. Similar results were also observed in the enterovirus 71 (EV71)-infected cells. Finally, we demonstrated that AUF1 was also recruited to arsenite-induced SGs, suggesting that the recruitment of AUF1 to SG is not a specific response to viral infection. In summary, our data indicate that both CVB3 and EV71 infections can induce SG formation, and AUF1 is a novel SG component upon the viral infections. Our findings may shed light on understanding the picornavirus-host interaction.
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Affiliation(s)
- Shuo Wu
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Lexun Lin
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Wenran Zhao
- Department of Cell Biology, Harbin Medical University, Harbin 150081, China
| | - Xiaobo Li
- Department of Pathology, Harbin Medical University, Harbin 150081, China
| | - Yan Wang
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Xiaoning Si
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Tianying Wang
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Heng Wu
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Xia Zhai
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Xiaoyan Zhong
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Shuoyang Gao
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Lei Tong
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Zhikai Xu
- Department of Microbiology, School of Basic Medicine, Fourth Military Medical University, Xi'an 710032, China.
| | - Zhaohua Zhong
- Department of Microbiology, Harbin Medical University, Harbin 150081, China.
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Activation of stress response pathways promotes formation of antiviral granules and restricts virus replication. Mol Cell Biol 2014; 34:2003-16. [PMID: 24662051 DOI: 10.1128/mcb.01630-13] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The formation of protein-RNA granules is a part of both natural cellular function (P-bodies and nuclear HNRNPs) and the response to cellular stress (stress granules and ND10 bodies). To better understand the role of stress-induced granules in viral infection, we have studied the ability of cells to restrict poxvirus replication through the formation of antiviral granules (AVGs). Of cells infected with a wild-type poxvirus, a small number spontaneously formed AVGs. In these AVG-positive cells, viral gene expression was inhibited. The addition of compounds that altered RNA helicase activity, induced oxidative stress, or stimulated translation initiation factor phosphorylation significantly increased the number of AVG-positive cells. When AVGs formed, both viral translation and titers were decreased even when host translation persisted. Treatment with the antiviral compound isatin β-thiosemicarbazone (IBT), a compound that was used to treat smallpox infections, induced AVGs, suggesting a role for these structures in the pharmacological inhibition of poxvirus replication. These findings provide evidence that AVGs are an innate host response that can be exogenously stimulated to combat virus infection. Since small molecules are able to stimulate AVG formation, it is a potential target for new antiviral development.
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Carroll K, Hastings C, Miller CL. Amino acids 78 and 79 of Mammalian Orthoreovirus protein µNS are necessary for stress granule localization, core protein λ2 interaction, and de novo virus replication. Virology 2013; 448:133-45. [PMID: 24314644 DOI: 10.1016/j.virol.2013.10.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 08/01/2013] [Accepted: 10/05/2013] [Indexed: 12/25/2022]
Abstract
At early times in Mammalian Orthoreovirus (MRV) infection, cytoplasmic inclusions termed stress granules (SGs) are formed as a component of the innate immune response, however, at later times they are no longer present despite continued immune signaling. To investigate the roles of MRV proteins in SG modulation we examined non-structural protein µNS localization relative to SGs in infected and transfected cells. Using a series of mutant plasmids, we mapped the necessary μNS residues for SG localization to amino acids 78 and 79. We examined the capacity of a μNS(78-79) mutant to associate with known viral protein binding partners of μNS and found that it loses association with viral core protein λ2. Finally, we show that while this mutant cannot support de novo viral replication, it is able to rescue replication following siRNA knockdown of μNS. These data suggest that μNS association with SGs, λ2, or both play roles in MRV replication.
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Affiliation(s)
- Kate Carroll
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames 50011, IA, USA; Program in Genetics, Iowa State University, Ames 50011, IA, USA
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Fitzgerald KD, Semler BL. Poliovirus infection induces the co-localization of cellular protein SRp20 with TIA-1, a cytoplasmic stress granule protein. Virus Res 2013; 176:223-31. [PMID: 23830997 PMCID: PMC3742715 DOI: 10.1016/j.virusres.2013.06.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 06/21/2013] [Accepted: 06/21/2013] [Indexed: 12/18/2022]
Abstract
Different types of environmental stress cause mammalian cells to form cytoplasmic foci, termed stress granules, which contain mRNPs that are translationally silenced. These foci are transient and dynamic, and contain components of the cellular translation machinery as well as certain mRNAs and RNA binding proteins. Stress granules are known to be induced by conditions such as hypoxia, nutrient deprivation, and oxidative stress, and a number of cellular factors have been identified that are commonly associated with these foci. More recently it was discovered that poliovirus infection also induces the formation of stress granules, although these cytoplasmic foci appear to be somewhat compositionally unique. Work described here examined the punctate pattern of SRp20 (a host cell mRNA splicing protein) localization in the cytoplasm of poliovirus-infected cells, demonstrating the partial co-localization of SRp20 with the stress granule marker protein TIA-1. We determined that SRp20 does not co-localize with TIA-1, however, under conditions of oxidative stress, indicating that the close association of these two proteins during poliovirus infection is not representative of a general response to cellular stress. We confirmed that the expression of a dominant negative version of TIA-1 (TIA-1-PRD) results in the dissociation of stress granules. Finally, we demonstrated that expression of wild type TIA-1 or dominant negative TIA-1-PRD in cells during poliovirus infection does not dramatically affect viral translation. Taken together, these studies provide a new example of the unique cytoplasmic foci that form during poliovirus infection.
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Affiliation(s)
| | - Bert L. Semler
- Corresponding author. Tel.: +1 949 824 7573; fax: +1 949 824 2694.
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Lloyd RE. Regulation of stress granules and P-bodies during RNA virus infection. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:317-31. [PMID: 23554219 PMCID: PMC3652661 DOI: 10.1002/wrna.1162] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
RNA granules are structures within cells that play major roles in gene expression and homeostasis. Two principle kinds of RNA granules are conserved from yeast to mammals: stress granules (SGs), which contain stalled translation initiation complexes, and processing bodies (P‐bodies, PBs), which are enriched with factors involved in RNA turnover. Since RNA granules are associated with silenced transcripts, viruses subvert RNA granule function for replicative advantages. This review, focusing on RNA viruses, discusses mechanisms that manipulate stress granules and P‐bodies to promote synthesis of viral proteins. Three main themes have emerged for how viruses manipulate RNA granules; (1) cleavage of key host factors, (2) control of protein kinase R (PKR) activation, and (3) redirecting RNA granule components for new or parallel roles in viral reproduction, at the same time disrupting RNA granules. Viruses utilize one or more of these routes to achieve robust and productive infection. WIREs RNA 2013, 4:317–331. doi: 10.1002/wrna.1162 This article is categorized under:
RNA in Disease and Development > RNA in Disease
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Affiliation(s)
- Richard E Lloyd
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA.
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50
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MDA5 localizes to stress granules, but this localization is not required for the induction of type I interferon. J Virol 2013; 87:6314-25. [PMID: 23536668 DOI: 10.1128/jvi.03213-12] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Virus infection can initiate a type I interferon (IFN-α/β) response via activation of the cytosolic RNA sensors retinoic acid-inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5). Furthermore, it can activate kinases that phosphorylate eukaryotic translation initiation factor 2α (eIF2α), which leads to inhibition of (viral) protein translation and formation of stress granules (SG). Most viruses have evolved mechanisms to suppress these cellular responses. Here, we show that a mutant mengovirus expressing an inactive leader (L) protein, which we have previously shown to be unable to suppress IFN-α/β, triggered SG formation in a protein kinase R (PKR)-dependent manner. Furthermore, we show that infection of cells that are defective in SG formation yielded higher viral RNA levels, suggesting that SG formation acts as an antiviral defense mechanism. Since the induction of both IFN-α/β and SG is suppressed by mengovirus L, we set out to investigate a potential link between these pathways. We observed that MDA5, the intracellular RNA sensor that recognizes picornaviruses, localized to SG. However, activation of the MDA5 signaling pathway did not trigger and was not required for SG formation. Moreover, cells that were unable to form SG-by protein kinase R (PKR) depletion, using cells expressing a nonphosphorylatable eIF2α protein, or by drug treatment that inhibits SG formation-displayed a normal IFN-α/β response. Thus, although MDA5 localizes to SG, this localization seems to be dispensable for induction of the IFN-α/β pathway.
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