1
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Welsh OL, Roth AN, Sutherland DM, Dermody TS. Sequence polymorphisms in the reovirus σ1 attachment protein modulate encapsidation efficiency and replication in mice. J Virol 2024; 98:e0030524. [PMID: 38771042 PMCID: PMC11237452 DOI: 10.1128/jvi.00305-24] [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: 02/16/2024] [Accepted: 04/23/2024] [Indexed: 05/22/2024] Open
Abstract
Many functions of viral attachment proteins are established, but less is known about the biological importance of viral attachment protein encapsidation efficiency. The mammalian orthoreovirus (reovirus) σ1 attachment protein forms filamentous trimers that incorporate into pentamers of the λ2 capsid protein. Reovirus strains vary in the efficiency of σ1 encapsidation onto progeny virions, which influences viral stability during entry into cells and the efficacy of tumor cell lysis. While the role of σ1 encapsidation has been evaluated in studies using cultured cells, the contribution of attachment protein encapsidation efficiency to viral infection in animals is less clear. Polymorphisms in reovirus σ1 at residues 22 and 249 have been implicated in viral dissemination in mice and susceptibility to proteolysis in the murine intestine, respectively. To determine whether these residues contribute to σ1 encapsidation efficiency, we engineered σ1 mutant viruses with single- and double-residue substitutions at sites 22 and 249. We found that substitutions at these sites alter the encapsidation of σ1 and that reoviruses encapsidating higher amounts of σ1 bind cells more avidly and have a modest replication advantage in a cell-type-specific manner relative to low σ1-encapsidating reoviruses. Furthermore, we found that a high σ1-encapsidating reovirus replicates and disseminates more efficiently in mice relative to a low σ1-encapsidating reovirus. These findings provide evidence of a relationship between viral attachment protein encapsidation efficiency and viral replication in cell culture and animal hosts. IMPORTANCE Viral attachment proteins can serve multiple functions during viral replication, including attachment to host cells, cell entry and disassembly, and modulation of host immune responses. The relationship between viral attachment protein encapsidation efficiency and viral replication in cells and animals is poorly understood. We engineered and characterized a panel of reoviruses that differ in the capacity to encapsidate the σ1 attachment protein. We found that strains encapsidating σ1 with higher efficiency bind cells more avidly and replicate and spread more efficiently in mice relative to those encapsidating σ1 with lower efficiency. These results highlight a function for σ1 attachment protein capsid abundance in viral replication in cells and animals, which may inform future use of reovirus as an oncolytic therapeutic.
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Affiliation(s)
- Olivia L. Welsh
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Alexa N. Roth
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Danica M. Sutherland
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Terence S. Dermody
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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2
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Abad AT, McNamara AJ, Danthi P. Proteasome activity is required for reovirus entry into cells. J Virol 2023; 97:e0134823. [PMID: 37830819 PMCID: PMC10617490 DOI: 10.1128/jvi.01348-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 09/04/2023] [Indexed: 10/14/2023] Open
Abstract
IMPORTANCE Due to their limited genetic capacity, viruses are reliant on multiple host systems to replicate successfully. Mammalian orthoreovirus (reovirus) is commonly used as a model system for understanding host-virus interactions. In this study, we identify that the proteasome system, which is critical for cellular protein turnover, affects reovirus entry. Inhibition of the proteasome using a chemical inhibitor blocks reovirus uncoating. Blocking these events reduces subsequent replication of the virus. This work identifies that additional host factors control reovirus entry.
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Affiliation(s)
- Andrew T. Abad
- Department of Biology, Indiana University, Bloomington, Indiana, USA
| | | | - Pranav Danthi
- Department of Biology, Indiana University, Bloomington, Indiana, USA
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3
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Huang WR, Wu YY, Liao TL, Nielsen BL, Liu HJ. Cell Entry of Avian Reovirus Modulated by Cell-Surface Annexin A2 and Adhesion G Protein-Coupled Receptor Latrophilin-2 Triggers Src and p38 MAPK Signaling Enhancing Caveolin-1- and Dynamin 2-Dependent Endocytosis. Microbiol Spectr 2023; 11:e0000923. [PMID: 37097149 PMCID: PMC10269738 DOI: 10.1128/spectrum.00009-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 04/05/2023] [Indexed: 04/26/2023] Open
Abstract
The specifics of cell receptor-modulated avian reovirus (ARV) entry remain unknown. By using a viral overlay protein-binding assay (VOPBA) and an in-gel digestion coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS), we determined that cell-surface annexin A2 (AnxA2) and adhesion G protein-coupled receptor Latrophilin-2 (ADGRL2) modulate ARV entry. Direct interaction between the ARV σC protein and AnxA2 and ADGRL2 in Vero and DF-1 cells was demonstrated in situ by proximity ligation assays. By using short hairpin RNAs (shRNAs) to silence the endogenous AnxA2 and ADGRL2 genes, ARV entry could be efficiently blocked. A significant decrease in virus yields and the intracellular specific signal for σC protein was observed in Vero cells preincubated with the specific AnxA2 and ADGRL2 monoclonal antibodies, indicating that AnxA2 and ADGRL2 are involved in modulating ARV entry. Furthermore, we found that cells pretreated with the AnxA2/S100A10 heterotetramer (A2t) inhibitor A2ti-1 suppressed ARV-mediated activation of Src and p38 mitogen-activated protein kinase (MAPK), demonstrating that Src and p38 MAPK serve as downstream molecules of cell-surface AnxA2 signaling. Our results reveal that suppression of cell-surface AnxA2 with the A2ti-1 inhibitor increased Csk-Cbp interaction, suggesting that ARV entry suppresses Cbp-mediated relocation of Csk to the membrane, thereby activating Src. Furthermore, reciprocal coimmunoprecipitation assays revealed that σC can interact with signaling molecules, lipid raft, and vimentin. The current study provides novel insights into cell-surface AnxA2- and ADGRL2-modulated cell entry of ARV which triggers Src and p38 MAPK signaling to enhance caveolin-1-, dynamin 2-, and lipid raft-dependent endocytosis. IMPORTANCE By analyzing results from VOPBA and LC-MS/MS, we have determined that cell-surface AnxA2 and ADGRL2 modulate ARV entry. After ARV binding to receptors, Src and p38 MAPK signaling were triggered and, in turn, increased the phosphorylation of caveolin-1 (Tyr14) and upregulated dynamin 2 expression to facilitate caveolin-1-mediated and dynamin 2-dependent endocytosis. In this work, we demonstrated that ARV triggers Src activation by impeding Cbp-mediated relocation of Csk to the membrane in the early stages of the life cycle. This work provides better insight into cell-surface AnxA2 and ADGRL2, which upregulate Src and p38MAPK signaling pathways to enhance ARV entry and productive infection.
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Affiliation(s)
- Wei-Ru Huang
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
- iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | - Yi-Ying Wu
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
- iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | - Tsai-Ling Liao
- Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan
- Ph.D Program in Translational Medicine, National Chung Hsing University, Taichung, Taiwan
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Brent L. Nielsen
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, USA
| | - Hung-Jen Liu
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
- iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
- Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan
- Ph.D Program in Translational Medicine, National Chung Hsing University, Taichung, Taiwan
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan
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4
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Sutherland DM, Strebl M, Koehler M, Welsh OL, Yu X, Hu L, dos Santos Natividade R, Knowlton JJ, Taylor GM, Moreno RA, Wörz P, Lonergan ZR, Aravamudhan P, Guzman-Cardozo C, Kour S, Pandey UB, Alsteens D, Wang Z, Prasad BVV, Stehle T, Dermody TS. NgR1 binding to reovirus reveals an unusual bivalent interaction and a new viral attachment protein. Proc Natl Acad Sci U S A 2023; 120:e2219404120. [PMID: 37276413 PMCID: PMC10268256 DOI: 10.1073/pnas.2219404120] [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: 11/14/2022] [Accepted: 04/19/2023] [Indexed: 06/07/2023] Open
Abstract
Nogo-66 receptor 1 (NgR1) binds a variety of structurally dissimilar ligands in the adult central nervous system to inhibit axon extension. Disruption of ligand binding to NgR1 and subsequent signaling can improve neuron outgrowth, making NgR1 an important therapeutic target for diverse neurological conditions such as spinal crush injuries and Alzheimer's disease. Human NgR1 serves as a receptor for mammalian orthoreovirus (reovirus), but the mechanism of virus-receptor engagement is unknown. To elucidate how NgR1 mediates cell binding and entry of reovirus, we defined the affinity of interaction between virus and receptor, determined the structure of the virus-receptor complex, and identified residues in the receptor required for virus binding and infection. These studies revealed that central NgR1 surfaces form a bridge between two copies of viral capsid protein σ3, establishing that σ3 serves as a receptor ligand for reovirus. This unusual binding interface produces high-avidity interactions between virus and receptor to prime early entry steps. These studies refine models of reovirus cell-attachment and highlight the evolution of viruses to engage multiple receptors using distinct capsid components.
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Affiliation(s)
- Danica M. Sutherland
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA15224
| | - Michael Strebl
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076Tübingen, Germany
| | - Melanie Koehler
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
| | - Olivia L. Welsh
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA15224
| | - Xinzhe Yu
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX77030
| | - Liya Hu
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX77030
| | - Rita dos Santos Natividade
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
| | - Jonathan J. Knowlton
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Cryo-Electron Microscopy and Tomography Core, Baylor College of Medicine, Houston, TX77030
| | - Gwen M. Taylor
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA15224
| | - Rodolfo A. Moreno
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX77030
| | - Patrick Wörz
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076Tübingen, Germany
| | - Zachery R. Lonergan
- Cryo-Electron Microscopy and Tomography Core, Baylor College of Medicine, Houston, TX77030
| | - Pavithra Aravamudhan
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA15224
| | - Camila Guzman-Cardozo
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA15224
| | - Sukhleen Kour
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
| | - Udai Bhan Pandey
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN37232
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, PA15261
| | - David Alsteens
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
- Children’s Neuroscience Institute, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA15224
| | - Zhao Wang
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX77030
- Walloon Excellence in Life Sciences and Biotechnology, 1300Wavre, Belgium
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX77030
| | - B. V. Venkataram Prasad
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX77030
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX77030
| | - Thilo Stehle
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076Tübingen, Germany
| | - Terence S. Dermody
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15224
- Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA15224
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA15219
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5
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Garcia ML, Danthi P. The Reovirus σ1 Attachment Protein Influences the Stability of Its Entry Intermediate. J Virol 2023; 97:e0058523. [PMID: 37167564 PMCID: PMC10231251 DOI: 10.1128/jvi.00585-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 05/13/2023] Open
Abstract
Structural metastability of viral capsids is pivotal for viruses to survive in harsh environments and to undergo timely conformational changes required for cell entry. Mammalian orthoreovirus (reovirus) is a model to study capsid metastability. Following initial disassembly of the reovirus particle mediated by proteases, a metastable intermediate called the infectious subvirion particle (ISVP) is generated. Using a σ1 monoreassortant virus, we recently showed that σ1 properties affect its encapsidation on particles and the metastability of ISVPs. How metastability is impacted by σ1 and whether the lower encapsidation level of σ1 is connected to this property is unknown. To define a correlation between encapsidation of σ1 and ISVP stability, we generated mutant viruses with single amino acid polymorphisms in σ1 or those that contain chimeric σ1 molecules composed of σ1 portions from type 1 and type 3 reovirus strains. We found that under most conditions where σ1 encapsidation on the particle was lower, ISVPs displayed lower stability. Characterization of mutant viruses selected for enhanced stability via a forward genetic approach also revealed that in some cases, σ1 properties influence stability without influencing σ1 encapsidation. These data indicate that σ1 can also influence ISVP stability independent of its level of incorporation. Together, our work reveals an underappreciated effect of the σ1 attachment protein on the properties of the reovirus capsid. IMPORTANCE Reovirus particles are comprised of eight proteins. Among them, the reovirus σ1 protein functions engages cellular receptors. σ1 also influences the stability of an entry intermediate called ISVP. Here, we sought to define the basis of the link between σ1 properties and stability of ISVPs. Using variety of mutant strains, we determined that when virus preparations contain particles with a high amount of encapsidated σ1, ISVP stability is higher. Additionally, we identified portions of σ1 that impact its encapsidation and consequently the stability of ISVPs. We also determined that in some cases, σ1 properties alter stability of ISVPs without affecting encapsidation. This work highlights that proteins of these complex particles are arranged in an intricate, interconnected manner such that changing the properties of these proteins has a profound impact on the remainder of the particle.
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Affiliation(s)
| | - Pranav Danthi
- Department of Biology, Indiana University, Bloomington, Indiana, USA
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6
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dos Santos Natividade R, Koehler M, Gomes PSFC, Simpson JD, Smith SC, Gomes DEB, de Lhoneux J, Yang J, Ray A, Dermody TS, Bernardi RC, Ogden KM, Alsteens D. Deciphering molecular mechanisms stabilizing the reovirus-binding complex. Proc Natl Acad Sci U S A 2023; 120:e2220741120. [PMID: 37186838 PMCID: PMC10214207 DOI: 10.1073/pnas.2220741120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 04/06/2023] [Indexed: 05/17/2023] Open
Abstract
Mammalian orthoreoviruses (reoviruses) serve as potential triggers of celiac disease and have oncolytic properties, making these viruses potential cancer therapeutics. Primary attachment of reovirus to host cells is mainly mediated by the trimeric viral protein, σ1, which engages cell-surface glycans, followed by high-affinity binding to junctional adhesion molecule-A (JAM-A). This multistep process is thought to be accompanied by major conformational changes in σ1, but direct evidence is lacking. By combining biophysical, molecular, and simulation approaches, we define how viral capsid protein mechanics influence virus-binding capacity and infectivity. Single-virus force spectroscopy experiments corroborated by in silico simulations show that GM2 increases the affinity of σ1 for JAM-A by providing a more stable contact interface. We demonstrate that conformational changes in σ1 that lead to an extended rigid conformation also significantly increase avidity for JAM-A. Although its associated lower flexibility impairs multivalent cell attachment, our findings suggest that diminished σ1 flexibility enhances infectivity, indicating that fine-tuning of σ1 conformational changes is required to successfully initiate infection. Understanding properties underlying the nanomechanics of viral attachment proteins offers perspectives in the development of antiviral drugs and improved oncolytic vectors.
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Affiliation(s)
- Rita dos Santos Natividade
- Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
| | - Melanie Koehler
- Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, 85354Freising, Germany
| | | | - Joshua D. Simpson
- Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
| | - Sydni Caet Smith
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, 37232Nashville, TN
| | | | - Juliette de Lhoneux
- Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
| | - Jinsung Yang
- Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
| | - Ankita Ray
- Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
| | - Terence S. Dermody
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA15213
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA15213
- Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center, Children’s Hospital of Pittsburgh, Pittsburgh, PA15213
| | | | - Kristen M. Ogden
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, 37232Nashville, TN
- Department of Pediatrics, Division of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN37232
| | - David Alsteens
- Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Université catholique de Louvain, 1348Louvain-la-Neuve, Belgium
- Walloon Excellence in Life sciences and Biotechnology, Walloon Excellence Research Institute, 1300Wavre, Belgium
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7
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Shang P, Simpson JD, Taylor GM, Sutherland DM, Welsh OL, Aravamudhan P, Natividade RDS, Schwab K, Michel JJ, Poholek AC, Wu Y, Rajasundaram D, Koehler M, Alsteens D, Dermody TS. Paired immunoglobulin-like receptor B is an entry receptor for mammalian orthoreovirus. Nat Commun 2023; 14:2615. [PMID: 37147336 PMCID: PMC10163058 DOI: 10.1038/s41467-023-38327-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 04/25/2023] [Indexed: 05/07/2023] Open
Abstract
Mammalian orthoreovirus (reovirus) infects most mammals and is associated with celiac disease in humans. In mice, reovirus infects the intestine and disseminates systemically to cause serotype-specific patterns of disease in the brain. To identify receptors conferring reovirus serotype-dependent neuropathogenesis, we conducted a genome-wide CRISPRa screen and identified paired immunoglobulin-like receptor B (PirB) as a receptor candidate. Ectopic expression of PirB allowed reovirus binding and infection. PirB extracelluar D3D4 region is required for reovirus attachment and infectivity. Reovirus binds to PirB with nM affinity as determined by single molecule force spectroscopy. Efficient reovirus endocytosis requires PirB signaling motifs. In inoculated mice, PirB is required for maximal replication in the brain and full neuropathogenicity of neurotropic serotype 3 (T3) reovirus. In primary cortical neurons, PirB expression contributes to T3 reovirus infectivity. Thus, PirB is an entry receptor for reovirus and contributes to T3 reovirus replication and pathogenesis in the murine brain.
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Affiliation(s)
- Pengcheng Shang
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Joshua D Simpson
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Gwen M Taylor
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Danica M Sutherland
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Olivia L Welsh
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Pavithra Aravamudhan
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Rita Dos Santos Natividade
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Kristina Schwab
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Joshua J Michel
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Amanda C Poholek
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yijen Wu
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Dhivyaa Rajasundaram
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Melanie Koehler
- Leibniz Institute for Food Systems Biology at the Technical University Munich, Freising, Germany
| | - David Alsteens
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- WELBIO Department, WEL Research Institute, Wavre, Belgium
| | - Terence S Dermody
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA.
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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8
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Ogawa K, Yamada K, Etoh T, Kitagawa M, Shirasaka Y, Noguchi K, Kobayashi T, Nishizono A, Inomata M. Development of an Oncolytic Mammalian Orthoreovirus Expressing the Near-Infrared Fluorescent Protein iRFP720. J Virol Methods 2022; 308:114574. [DOI: 10.1016/j.jviromet.2022.114574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/13/2022] [Accepted: 07/01/2022] [Indexed: 11/30/2022]
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9
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An Unusual Aspartic Acid Cluster in the Reovirus Attachment Fiber σ1 Mediates Stability at Low pH and Preserves Trimeric Organization. J Virol 2022; 96:e0033122. [PMID: 35380459 DOI: 10.1128/jvi.00331-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The reovirus attachment protein σ1 mediates cell attachment and receptor binding and is thought to undergo conformational changes during viral disassembly. σ1 is a trimeric filamentous protein with an α-helical coiled-coil tail, a triple-β-spiral body, and a globular head. At the trimer interface, the head domain features an unusual and conserved aspartic acid cluster, which forms the only significant intratrimer interactions in the head and must be protonated to allow trimer formation. To define the role of pH on σ1 stability and conformation, we tested its domains over a wide range of pH values. We show that all domains of σ1 are remarkably thermostable, even at the low pH of the stomach. We determined the optimal pH for stability to be between pHs 5 and 6, a value close to the pH of the endosome and of the jejunum. The σ1 head is stable at acidic and neutral pH but detrimerizes at basic pH. When Asp345 in the aspartic acid cluster is mutated to asparagine (D345N), the σ1 head loses stability at low pH and is more prone to detrimerize. Although the D345N mutation does not affect σ1 binding affinity for the JAM-A receptor, the overall binding stoichiometry is reduced by one-third. The additional replacement of the neighboring His349 with alanine disrupts inner trimer surface interactions, leading to a less thermostable and monomeric σ1 D345N head that fails to bind the JAM-A receptor. When the body is expressed together with the head domain, the thermostability is restored and the stoichiometry of the binding to JAM-A receptor is preserved. Our results confirm a fundamental role of the aspartic acid cluster as a pH-dependent molecular switch controlling trimerization and enhancing thermostability of σ1, which represent essential requirements to accomplish reovirus infection and entry and might be common mechanisms among other enteric viruses. IMPORTANCE Enteric viruses withstand the highly acidic environment of the stomach during transmission, and many of them use low pH as a trigger for conformational changes associated with entry. For many nonenveloped viruses, the structural basis of these effects is not clear. We have investigated the stability of the reovirus attachment protein σ1 over a range of pHs and find it to be remarkably thermostable, especially at low pH. We identify a role for the aspartic acid cluster in maintaining σ1 thermostability, trimeric organization, and binding to JAM-A receptor especially at the gastric pH reovirus has to withstand while passing the stomach. The understanding of monomer-trimer dynamics within σ1 enhances our knowledge of reovirus entry and has implications for stability and transmission of other enteric viruses.
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10
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Gastrointestinal cancer-associated fibroblasts expressing Junctional Adhesion Molecule-A are amenable to infection by oncolytic reovirus. Cancer Gene Ther 2022; 29:1918-1929. [PMID: 35869278 PMCID: PMC9750869 DOI: 10.1038/s41417-022-00507-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 06/13/2022] [Accepted: 07/06/2022] [Indexed: 01/25/2023]
Abstract
Gastrointestinal (GI) cancers are characterized by extensive tumor stroma that both promotes tumor progression and acts as a physical barrier for adjacent tumor cells, limiting the effect of current treatment modalities. Oncolytic virotherapy is currently investigated in clinical trials as a novel therapeutic agent for different malignancies of the GI tract, but it is largely unknown whether these viruses can also target the tumor stroma. Here, we investigated the tropism of two commonly studied OVs, adenovirus and reovirus, towards primary GI fibroblasts from human oesophageal, gastric, duodenal and pancreatic carcinomas (N = 36). GI fibroblasts were susceptible to type 3 Dearing (T3D) strain R124 and bioselected mutant reovirus (jin-3) infection but not oncolytic adenovirus (Ad5-Δ24). Efficient infection and apoptosis of human and mouse GI cancer-derived fibroblasts by these reoviruses was partially dependent on the expression of the reovirus entry receptor, Junctional Adhesion Molecule-A (JAM-A). Moreover, human GI cancer organoid-fibroblast co-cultures showed higher overall infectivity when containing JAM-A expressing fibroblasts as compared to JAM-A negative fibroblasts, indicating a potential role of JAM-A expressing fibroblasts for viral dissemination. We further show that JAM-A is not only necessary for efficient reovirus infection of fibroblasts but also partially mediates reovirus-induced apoptosis, dependent on signaling through the C-terminal PDZ-domain of JAM-A. Altogether, our data show the presence of JAM-A expressing fibroblasts in both human and murine GI cancers that are amenable to infection and induction of apoptosis by reovirus, extending the potential anti-cancer actions of reovirus with stromal targeting.
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11
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Yang J, Wang J, Peng X, Lei C, Sun X, Hu J. Heat shock protein 70, glutamate dehydrogenase, and angiotensin-converting enzyme of Bombyx mori mediate the cell attachment of Cypovirus 1. J Gen Virol 2021; 102. [PMID: 34914573 DOI: 10.1099/jgv.0.001710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dendrolimus punctatus causes great damage to pine forests worldwide. Dendrolimus punctatus cypovirus 1 (DpCPV-1) is an important pathogen of D. punctatus. However, the mechanism of DpCPV-1 cell entry has not been elucidated. In this study, we revealed that both GTase and MTase domains of VP3 (B-spike) and VP4 (A-spike) of DpCPV-1 interacted with the midgut proteins of Bombyx mori. Binding and competition assays revealed that GTase, MTase and VP4 played roles as viral attachment proteins. Far-Western blotting and LC-MS/MS analyses identified that heat shock protein 70 (BmHSP70), glutamate dehydrogenase (BmGDH), and angiotensin-converting enzyme (BmACE) in the midgut proteins as ligand candidates of the viral attachment proteins, and this was further verified by co-immunoprecipitation and fluorescence co-localization assays. Viral binding to the host midgut in vitro was inhibited by pre-treating B. mori midgut proteins with anti-BmHSP70, anti-BmGDH, anti-BmACE antibodies singly and in combination. Incubating DpCPV-1 virions with prokaryotically expressed BmHSP70, BmGDH, and BmACE also decreased viral attachment to the host midgut. In vivo bioassays revealed that viral infection in Helicoverpa armigera was partially neutralized by BmHSP70, BmGDH, and BmACE. Taking together, we concluded that HSP70, GDH, and ACE mediate DpCPV attachment and entry via binding to the viral attachment proteins, VP3 and VP4. The findings provide foundation for further understanding the entry mechanisms of cypoviruses.
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Affiliation(s)
- Jian Yang
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, PR China.,University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Jia Wang
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, PR China.,University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Xiaowei Peng
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, PR China.,University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Chengfeng Lei
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, PR China
| | - Xiulian Sun
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, PR China
| | - Jia Hu
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, PR China
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12
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Koehler M, Petitjean SJL, Yang J, Aravamudhan P, Somoulay X, Lo Giudice C, Poncin MA, Dumitru AC, Dermody TS, Alsteens D. Reovirus directly engages integrin to recruit clathrin for entry into host cells. Nat Commun 2021; 12:2149. [PMID: 33846319 PMCID: PMC8041799 DOI: 10.1038/s41467-021-22380-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 03/09/2021] [Indexed: 02/01/2023] Open
Abstract
Reovirus infection requires the concerted action of viral and host factors to promote cell entry. After interaction of reovirus attachment protein σ1 with cell-surface carbohydrates and proteinaceous receptors, additional host factors mediate virus internalization. In particular, β1 integrin is required for endocytosis of reovirus virions following junctional adhesion molecule A (JAM-A) binding. While integrin-binding motifs in the surface-exposed region of reovirus capsid protein λ2 are thought to mediate integrin interaction, evidence for direct β1 integrin-reovirus interactions and knowledge of how integrins function to mediate reovirus entry is lacking. Here, we use single-virus force spectroscopy and confocal microscopy to discover a direct interaction between reovirus and β1 integrins. Comparison of interactions between reovirus disassembly intermediates as well as mutants and β1 integrin show that λ2 is the integrin ligand. Finally, using fluidic force microscopy, we demonstrate a functional role for β1 integrin interaction in promoting clathrin recruitment to cell-bound reovirus. Our study demonstrates a direct interaction between reovirus and β1 integrins and offers insights into the mechanism of reovirus cell entry. These results provide new perspectives for the development of efficacious antiviral therapeutics and the engineering of improved viral gene delivery and oncolytic vectors.
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Affiliation(s)
- Melanie Koehler
- grid.7942.80000 0001 2294 713XLouvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Simon J. L. Petitjean
- grid.7942.80000 0001 2294 713XLouvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Jinsung Yang
- grid.7942.80000 0001 2294 713XLouvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Pavithra Aravamudhan
- grid.21925.3d0000 0004 1936 9000Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA USA ,grid.239553.b0000 0000 9753 0008Institute of Infection, Inflammation and Immunity, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA USA
| | - Xayathed Somoulay
- grid.21925.3d0000 0004 1936 9000Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA USA ,grid.239553.b0000 0000 9753 0008Institute of Infection, Inflammation and Immunity, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA USA
| | - Cristina Lo Giudice
- grid.7942.80000 0001 2294 713XLouvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Mégane A. Poncin
- grid.7942.80000 0001 2294 713XLouvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Andra C. Dumitru
- grid.7942.80000 0001 2294 713XLouvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Terence S. Dermody
- grid.21925.3d0000 0004 1936 9000Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA USA ,grid.239553.b0000 0000 9753 0008Institute of Infection, Inflammation and Immunity, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA USA ,grid.21925.3d0000 0004 1936 9000Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA USA
| | - David Alsteens
- grid.7942.80000 0001 2294 713XLouvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium ,grid.509491.0Walloon Excellence in Life sciences and Biotechnology (WELBIO), Wavre, Belgium
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13
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Sialic Acid Receptors: The Key to Solving the Enigma of Zoonotic Virus Spillover. Viruses 2021; 13:v13020262. [PMID: 33567791 PMCID: PMC7915228 DOI: 10.3390/v13020262] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 01/31/2021] [Accepted: 02/01/2021] [Indexed: 12/14/2022] Open
Abstract
Emerging viral diseases are a major threat to global health, and nearly two-thirds of emerging human infectious diseases are zoonotic. Most of the human epidemics and pandemics were caused by the spillover of viruses from wild mammals. Viruses that infect humans and a wide range of animals have historically caused devastating epidemics and pandemics. An in-depth understanding of the mechanisms of viral emergence and zoonotic spillover is still lacking. Receptors are major determinants of host susceptibility to viruses. Animal species sharing host cell receptors that support the binding of multiple viruses can play a key role in virus spillover and the emergence of novel viruses and their variants. Sialic acids (SAs), which are linked to glycoproteins and ganglioside serve as receptors for several human and animal viruses. In particular, influenza and coronaviruses, which represent two of the most important zoonotic threats, use SAs as cellular entry receptors. This is a comprehensive review of our current knowledge of SA receptor distribution among animal species and the range of viruses that use SAs as receptors. SA receptor tropism and the predicted natural susceptibility to viruses can inform targeted surveillance of domestic and wild animals to prevent the future emergence of zoonotic viruses.
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14
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Reovirus σ1 Conformational Flexibility Modulates the Efficiency of Host Cell Attachment. J Virol 2020; 94:JVI.01163-20. [PMID: 32938765 DOI: 10.1128/jvi.01163-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/09/2020] [Indexed: 02/07/2023] Open
Abstract
Reovirus attachment protein σ1 is a trimeric molecule containing tail, body, and head domains. During infection, σ1 engages sialylated glycans and junctional adhesion molecule-A (JAM-A), triggering uptake into the endocytic compartment, where virions are proteolytically converted to infectious subvirion particles (ISVPs). Further disassembly allows σ1 release and escape of transcriptionally active reovirus cores into the cytosol. Electron microscopy has revealed a distinct conformational change in σ1 from a compact form on virions to an extended form on ISVPs. To determine the importance of σ1 conformational mobility, we used reverse genetics to introduce cysteine mutations that can cross-link σ1 by establishing disulfide bonds between structurally adjacent sites in the tail, body, and head domains. We detected phenotypic differences among the engineered viruses. A mutant with a cysteine pair in the head domain replicates with enhanced kinetics, forms large plaques, and displays increased avidity for JAM-A relative to the parental virus, mimicking properties of ISVPs. However, unlike ISVPs, particles containing cysteine mutations that cross-link the head domain uncoat and transcribe viral positive-sense RNA with kinetics similar to the parental virus and are sensitive to ammonium chloride, which blocks virion-to-ISVP conversion. Together, these data suggest that σ1 conformational flexibility modulates the efficiency of reovirus host cell attachment.IMPORTANCE Nonenveloped virus entry is an incompletely understood process. For reovirus, the functional significance of conformational rearrangements in the attachment protein, σ1, that occur during entry and particle uncoating are unknown. We engineered and characterized reoviruses containing cysteine mutations that cross-link σ1 monomers in nonreducing conditions. We found that the introduction of a cysteine pair in the receptor-binding domain of σ1 yielded a virus that replicates with faster kinetics than the parental virus and forms larger plaques. Using functional assays, we found that cross-linking the σ1 receptor-binding domain modulates reovirus attachment but not uncoating or transcription. These data suggest that σ1 conformational rearrangements mediate the efficiency of reovirus host cell binding.
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15
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Generation of Genetically RGD σ1-Modified Oncolytic Reovirus That Enhances JAM-A-Independent Infection of Tumor Cells. J Virol 2020; 94:JVI.01703-20. [PMID: 32907973 DOI: 10.1128/jvi.01703-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 08/30/2020] [Indexed: 12/14/2022] Open
Abstract
Mammalian reovirus (MRV) strain type 3 Dearing (T3D) is a naturally occurring oncolytic virus that has been developed as a potential cancer therapeutic. However, MRV treatment cannot be applied to cancer cells expressing low levels of junctional adhesion molecule A (JAM-A), which is the entry receptor of MRV. In this study, we developed a reverse genetics system for MRV strain T3D-L, which showed high oncolytic potency. To modify the cell tropism of MRV, an arginine-glycine-aspartic acid (RGD) peptide with an affinity to integrin was inserted at the C terminus or loop structures of the viral cell attachment protein σ1. The recombinant RGD σ1-modified viruses induced remarkable cell lysis in human cancer cell lines with marginal JAM-A expression and in JAM-A knockout cancer cell lines generated by a CRISPR/Cas9 system. Pretreatment of cells with anti-integrin antibody decreased cell death caused by the RGD σ1-modified virus, suggesting the infection to the cells was via a specific interaction with integrin αV. By using mouse models, we assessed virulence of the RGD σ1-modified viruses in vivo This system will open new avenues for the use of genetically modified oncolytic MRV for use as a cancer therapy.IMPORTANCE Oncolytic viruses kill tumors without affecting normal cells. A variety of oncolytic viruses are used as cancer therapeutics. Mammalian reovirus (MRV), which belongs to the genus Orthoreovirus, family Reoviridae, is one such natural oncolytic virus. The anticancer effects of MRV are being evaluated in clinical trials. Unlike other oncolytic viruses, MRV has not been genetically modified for use as a cancer therapeutic in clinical trials. Here, we used a reverse genetic approach to introduce an integrin-affinity peptide sequence into the MRV cell attachment protein σ1 to alter the natural tropism of the virus. The recombinant viruses were able to infect cancer cell lines expressing very low levels of the MRV entry receptor, junctional adhesion molecule A (JAM-A), and cause tumor cell death while maintaining its original tropism via JAM-A. This is a novel report of a genetically modified oncolytic MRV by introducing a peptide sequence into σ1.
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16
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Orsay Virus CP-δ Adopts a Novel β-Bracelet Structural Fold and Incorporates into Virions as a Head Fiber. J Virol 2020; 94:JVI.01560-20. [PMID: 32817218 PMCID: PMC7565637 DOI: 10.1128/jvi.01560-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 08/08/2020] [Indexed: 11/20/2022] Open
Abstract
Viruses often have extended fibers to mediate host cell recognition and entry, serving as promising targets for antiviral drug development. Unlike other known viral fibers, the δ proteins from the three recently discovered nematode viruses are incorporated into infectious particles as protruding fibers covalently linked to the capsid. Crystal structures of δ revealed novel pentameric folding repeats, which we term β-bracelets, in the intermediate shaft region. Based on sequence analysis, the β-bracelet motif of δ is conserved in all three nematode viruses and could account for ∼60% of the total length of the fiber. Our study indicated that δ plays important roles in cell attachment for this group of nematode viruses. In addition, the tightly knitted β-bracelet fold, which presumably allows δ to survive harsh environments in the worm gut, could be applicable to bioengineering applications given its potentially high stability. Fiber proteins are commonly found in eukaryotic and prokaryotic viruses, where they play important roles in mediating viral attachment and host cell entry. They typically form trimeric structures and are incorporated into virions via noncovalent interactions. Orsay virus, a small RNA virus which specifically infects the laboratory model nematode Caenorhabditis elegans, encodes a fibrous protein δ that can be expressed as a free protein and as a capsid protein-δ (CP-δ) fusion protein. Free δ has previously been demonstrated to facilitate viral exit following intracellular expression; however, the biological significance and prevalence of CP-δ remained relatively unknown. Here, we demonstrate that Orsay CP-δ is covalently incorporated into infectious particles, the first example of any attached viral fibers known to date. The crystal structure of δ(1–101) (a deletion mutant containing the first 101 amino acid [aa] residues of δ) reveals a pentameric, 145-Å long fiber with an N-terminal coiled coil followed by multiple β-bracelet repeats. Electron micrographs of infectious virions depict particle-associated CP-δ fibers with dimensions similar to free δ. The δ proteins from two other nematode viruses, Le Blanc and Santeuil, which both specifically infect Caenorhabditis briggsae, were also found to form fibrous molecules. Recombinant Le Blanc δ was able to block Orsay virus infection in worm culture and vice versa, suggesting these two viruses likely compete for the same cell receptor(s). Thus, we propose that while CP-δ likely mediates host cell attachment for all three nematode viruses, additional downstream factor(s) ultimately determine the host specificity and range of each virus. IMPORTANCE Viruses often have extended fibers to mediate host cell recognition and entry, serving as promising targets for antiviral drug development. Unlike other known viral fibers, the δ proteins from the three recently discovered nematode viruses are incorporated into infectious particles as protruding fibers covalently linked to the capsid. Crystal structures of δ revealed novel pentameric folding repeats, which we term β-bracelets, in the intermediate shaft region. Based on sequence analysis, the β-bracelet motif of δ is conserved in all three nematode viruses and could account for ∼60% of the total length of the fiber. Our study indicated that δ plays important roles in cell attachment for this group of nematode viruses. In addition, the tightly knitted β-bracelet fold, which presumably allows δ to survive harsh environments in the worm gut, could be applicable to bioengineering applications given its potentially high stability.
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17
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Ins and Outs of Reovirus: Vesicular Trafficking in Viral Entry and Egress. Trends Microbiol 2020; 29:363-375. [PMID: 33008713 PMCID: PMC7523517 DOI: 10.1016/j.tim.2020.09.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 12/11/2022]
Abstract
Cell entry and egress are essential steps in the viral life cycle that govern pathogenesis and spread. Mammalian orthoreoviruses (reoviruses) are nonenveloped viruses implicated in human disease that serve as tractable models for studies of pathogen-host interactions. In this review we discuss the function of intracellular vesicular transport systems in reovirus entry, trafficking, and egress and comment on shared themes for diverse viruses. Designing strategic therapeutic interventions that impede these steps in viral replication requires a detailed understanding of mechanisms by which viruses coopt vesicular trafficking. We illuminate such targets, which may foster development of antiviral agents.
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18
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Berry JTL, Muñoz LE, Rodríguez Stewart RM, Selvaraj P, Mainou BA. Doxorubicin Conjugation to Reovirus Improves Oncolytic Efficacy in Triple-Negative Breast Cancer. Mol Ther Oncolytics 2020; 18:556-572. [PMID: 32995480 PMCID: PMC7493048 DOI: 10.1016/j.omto.2020.08.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 08/18/2020] [Indexed: 12/31/2022] Open
Abstract
Breast cancer is the second leading cause of cancer-related deaths in women in the United States. The triple-negative breast cancer (TNBC) subtype associates with higher rates of relapse, shorter overall survival, and aggressive metastatic disease. Hormone therapy is ineffective against TNBC, leaving patients with limited therapeutic options. Mammalian orthoreovirus (reovirus) preferentially infects and kills transformed cells, and a genetically engineered reassortant reovirus infects and kills TNBC cells more efficiently than prototypical strains. Reovirus oncolytic efficacy is further augmented by combination with topoisomerase inhibitors, including the frontline chemotherapeutic doxorubicin. However, long-term doxorubicin use correlates with toxicity to healthy tissues. Here, we conjugated doxorubicin to reovirus (reo-dox) to control drug delivery and enhance reovirus-mediated oncolysis. Our data indicate that conjugation does not impair viral biology and enhances reovirus oncolytic capacity in TNBC cells. Reo-dox infection promotes innate immune activation, and crosslinked doxorubicin retains DNA-damaging properties within infected cells. Importantly, reovirus and reo-dox significantly reduce primary TNBC tumor burden in vivo, with greater reduction in metastatic burden after reo-dox inoculation. Together, these data demonstrate that crosslinking chemotherapeutic agents to oncolytic viruses facilitates functional drug delivery to cells targeted by the virus, making it a viable approach for combination therapy against TNBC.
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Affiliation(s)
- Jameson T L Berry
- Emory University School of Medicine, Emory University, Atlanta, GA 30032, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30032, USA
| | - Luis E Muñoz
- Emory University School of Medicine, Emory University, Atlanta, GA 30032, USA
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30032, USA
| | - Roxana M Rodríguez Stewart
- Emory University School of Medicine, Emory University, Atlanta, GA 30032, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30032, USA
| | - Periasamy Selvaraj
- Emory University School of Medicine, Emory University, Atlanta, GA 30032, USA
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30032, USA
| | - Bernardo A Mainou
- Emory University School of Medicine, Emory University, Atlanta, GA 30032, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30032, USA
- Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
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19
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Heinemann U, Schuetz A. Structural Features of Tight-Junction Proteins. Int J Mol Sci 2019; 20:E6020. [PMID: 31795346 PMCID: PMC6928914 DOI: 10.3390/ijms20236020] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/25/2019] [Accepted: 11/26/2019] [Indexed: 12/14/2022] Open
Abstract
Tight junctions are complex supramolecular entities composed of integral membrane proteins, membrane-associated and soluble cytoplasmic proteins engaging in an intricate and dynamic system of protein-protein interactions. Three-dimensional structures of several tight-junction proteins or their isolated domains have been determined by X-ray crystallography, nuclear magnetic resonance spectroscopy, and cryo-electron microscopy. These structures provide direct insight into molecular interactions that contribute to the formation, integrity, or function of tight junctions. In addition, the known experimental structures have allowed the modeling of ligand-binding events involving tight-junction proteins. Here, we review the published structures of tight-junction proteins. We show that these proteins are composed of a limited set of structural motifs and highlight common types of interactions between tight-junction proteins and their ligands involving these motifs.
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Affiliation(s)
- Udo Heinemann
- Macromolecular Structure and Interaction Laboratory, Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Anja Schuetz
- Protein Production & Characterization Platform, Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
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20
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Enhanced Killing of Triple-Negative Breast Cancer Cells by Reassortant Reovirus and Topoisomerase Inhibitors. J Virol 2019; 93:JVI.01411-19. [PMID: 31511390 DOI: 10.1128/jvi.01411-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 09/09/2019] [Indexed: 12/12/2022] Open
Abstract
Breast cancer is the second leading cause of cancer-related deaths in women in the United States. Triple-negative breast cancer constitutes a subset of breast cancer that is associated with higher rates of relapse, decreased survival, and limited therapeutic options for patients afflicted with this type of breast cancer. Mammalian orthoreovirus (reovirus) selectively infects and kills transformed cells, and a serotype 3 reovirus is in clinical trials to assess its efficacy as an oncolytic agent against several cancers. It is unclear if reovirus serotypes differentially infect and kill triple-negative breast cancer cells and if reovirus-induced cytotoxicity of breast cancer cells can be enhanced by modulating the activity of host molecules and pathways. Here, we generated reassortant reoviruses by forward genetics with enhanced infective and cytotoxic properties in triple-negative breast cancer cells. From a high-throughput screen of small-molecule inhibitors, we identified topoisomerase inhibitors as a class of drugs that enhance reovirus infectivity and cytotoxicity of triple-negative breast cancer cells. Treatment of triple-negative breast cancer cells with topoisomerase inhibitors activates DNA damage response pathways, and reovirus infection induces robust production of type III, but not type I, interferon (IFN). Although type I and type III IFNs can activate STAT1 and STAT2, triple-negative breast cancer cellular proliferation is only negatively affected by type I IFN. Together, these data show that reassortant viruses with a novel genetic composition generated by forward genetics in combination with topoisomerase inhibitors more efficiently infect and kill triple-negative breast cancer cells.IMPORTANCE Patients afflicted by triple-negative breast cancer have decreased survival and limited therapeutic options. Reovirus infection results in cell death of a variety of cancers, but it is unknown if different reovirus types lead to triple-negative breast cancer cell death. In this study, we generated two novel reoviruses that more efficiently infect and kill triple-negative breast cancer cells. We show that infection in the presence of DNA-damaging agents enhances infection and triple-negative breast cancer cell killing by reovirus. These data suggest that a combination of a genetically engineered oncolytic reovirus and topoisomerase inhibitors may provide a potent therapeutic option for patients afflicted with triple-negative breast cancer.
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21
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Jayawardena N, Burga LN, Poirier JT, Bostina M. Virus-Receptor Interactions: Structural Insights For Oncolytic Virus Development. Oncolytic Virother 2019; 8:39-56. [PMID: 31754615 PMCID: PMC6825474 DOI: 10.2147/ov.s218494] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 10/02/2019] [Indexed: 12/11/2022] Open
Abstract
Recent advancements in oncolytic virotherapy commend a special attention to developing new strategies for targeting cancer cells with oncolytic viruses (OVs). Modifications of the viral envelope or coat proteins serve as a logical mean of repurposing viruses for cancer treatment. In this review, we discuss how detailed structural knowledge of the interactions between OVs and their natural receptors provide valuable insights into tumor specificity of some viruses and re-targeting of alternate receptors for broad tumor tropism or improved tumor selectivity.
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Affiliation(s)
- Nadishka Jayawardena
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Laura N Burga
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - John T Poirier
- Perlmutter Cancer Center, NYU Langone Health, New York, NY, USA
| | - Mihnea Bostina
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
- Otago Micro and Nano Imaging, University of Otago, Dunedin, New Zealand
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22
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Koehler M, Aravamudhan P, Guzman-Cardozo C, Dumitru AC, Yang J, Gargiulo S, Soumillion P, Dermody TS, Alsteens D. Glycan-mediated enhancement of reovirus receptor binding. Nat Commun 2019; 10:4460. [PMID: 31575869 PMCID: PMC6773860 DOI: 10.1038/s41467-019-12411-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 09/06/2019] [Indexed: 01/10/2023] Open
Abstract
Viral infection is an intricate process that requires the concerted action of both viral and host cell components. Entry of viruses into cells is initiated by interactions between viral proteins and their cell surface receptors. Despite recent progress, the molecular mechanisms underlying the multistep reovirus entry process are poorly understood. Using atomic force microscopy, we investigated how the reovirus σ1 attachment protein binds to both α-linked sialic acid (α-SA) and JAM-A cell-surface receptors. We discovered that initial σ1 binding to α-SA favors a strong multivalent anchorage to JAM-A. The enhanced JAM-A binding by virions following α-SA engagement is comparable to JAM-A binding by infectious subvirion particles (ISVPs) in the absence of α-SA. Since ISVPs have an extended σ1 conformer, this finding suggests that α-SA binding triggers a conformational change in σ1. These results provide new insights into the function of viral attachment proteins in the initiation of infection and open new avenues for the use of reoviruses as oncolytic agents.
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Affiliation(s)
- Melanie Koehler
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Pavithra Aravamudhan
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Center for Microbial Pathogenesis, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Camila Guzman-Cardozo
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Center for Microbial Pathogenesis, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Andra C Dumitru
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Jinsung Yang
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Serena Gargiulo
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Patrice Soumillion
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Terence S Dermody
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- Center for Microbial Pathogenesis, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA.
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| | - David Alsteens
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
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23
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Teige LH, Kumar S, Johansen GM, Wessel Ø, Vendramin N, Lund M, Rimstad E, Boysen P, Dahle MK. Detection of Salmonid IgM Specific to the Piscine Orthoreovirus Outer Capsid Spike Protein Sigma 1 Using Lipid-Modified Antigens in a Bead-Based Antibody Detection Assay. Front Immunol 2019; 10:2119. [PMID: 31552049 PMCID: PMC6743345 DOI: 10.3389/fimmu.2019.02119] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 08/22/2019] [Indexed: 11/13/2022] Open
Abstract
Bead-based multiplex immunoassays are promising tools for determination of the specific humoral immune response. In this study, we developed a multiplexed bead-based immunoassay for the detection of Atlantic salmon (Salmo salar) antibodies against Piscine orthoreovirus (PRV). Three different genotypes of PRV (PRV-1, PRV-2, and PRV-3) cause disease in farmed salmonids. The PRV outer capsid spike protein σ1 is predicted to be a host receptor binding protein and a target for neutralizing and protective antibodies. While recombinant σ1 performed poorly as an antigen to detect specific antibodies, N-terminal lipid modification of recombinant PRV-1 σ1 enabled sensitive detection of specific IgM in the bead-based assay. The specificity of anti-PRV-1 σ1 antibodies was confirmed by western blotting and pre-adsorption of plasma. Binding of non-specific IgM to beads coated with control antigens also increased after PRV infection, indicating a release of polyreactive antibodies. This non-specific binding was reduced by heat treatment of plasma. The same immunoassay also detected anti-PRV-3 σ1 antibodies from infected rainbow trout. In summary, a refined bead based immunoassay created by N-terminal lipid-modification of the PRV-1 σ1 antigen allowed sensitive detection of anti-PRV-1 and anti-PRV-3 antibodies from salmonids.
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Affiliation(s)
- Lena Hammerlund Teige
- Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, Oslo, Norway
| | - Subramani Kumar
- Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, Oslo, Norway.,Stem Cell and Cancer Biology Lab, Centre for Biotechnology, Anna University, Chennai, India
| | - Grethe M Johansen
- Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, Oslo, Norway
| | - Øystein Wessel
- Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, Oslo, Norway
| | - Niccolò Vendramin
- National Institute of Aquatic Resources, Technical University of Denmark, Lyngby, Denmark
| | - Morten Lund
- Department of Fish Health, Norwegian Veterinary Institute, Oslo, Norway.,PatoGen, Alesund, Norway
| | - Espen Rimstad
- Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, Oslo, Norway
| | - Preben Boysen
- Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, Oslo, Norway
| | - Maria K Dahle
- Department of Fish Health, Norwegian Veterinary Institute, Oslo, Norway
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24
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Song H, Zhao Z, Chai Y, Jin X, Li C, Yuan F, Liu S, Gao Z, Wang H, Song J, Vazquez L, Zhang Y, Tan S, Morel CM, Yan J, Shi Y, Qi J, Gao F, Gao GF. Molecular Basis of Arthritogenic Alphavirus Receptor MXRA8 Binding to Chikungunya Virus Envelope Protein. Cell 2019; 177:1714-1724.e12. [PMID: 31080063 DOI: 10.1016/j.cell.2019.04.008] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 02/07/2019] [Accepted: 04/01/2019] [Indexed: 01/17/2023]
Abstract
Arthritogenic alphaviruses, such as Chikungunya virus (CHIKV), cause severe and debilitating rheumatic diseases worldwide, resulting in severe morbidity and economic costs. Recently, MXRA8 was reported as an entry receptor. Here, we present the crystal structures of the mouse MXRA8, human MXRA8 in complex with the CHIKV E protein, and the cryo-electron microscopy structure of human MXRA8 and CHIKV virus-like particle. MXRA8 has two Ig-like domains with unique structural topologies. This receptor binds in the "canyon" between two protomers of the E spike on the surface of the virion. The atomic details at the interface between the two binding entities reveal that both the two domains and the hinge region of MXRA8 are involved in interaction with CHIKV E1-E2 residues from two protomers. Notably, the stalk region of MXRA8 is critical for CHIKV virus entry. This finding provides important information regarding the development of therapeutic countermeasures against those arthritogenic alphaviruses.
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Affiliation(s)
- Hao Song
- Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhennan Zhao
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan Chai
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiyue Jin
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Changyao Li
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Fei Yuan
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Sheng Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhengrong Gao
- Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Haiyuan Wang
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China
| | - Jian Song
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Leonardo Vazquez
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; National Institute of Science and Technology for Innovation on Diseases of Neglected Populations (INCT-IDPN), Center for Technological Development in Health (CDTS), Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, Rio de Janeiro 21040-361, Brazil
| | - Yanfang Zhang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuguang Tan
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Carlos M Morel
- National Institute of Science and Technology for Innovation on Diseases of Neglected Populations (INCT-IDPN), Center for Technological Development in Health (CDTS), Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, Rio de Janeiro 21040-361, Brazil
| | - Jinghua Yan
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yi Shi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Influenza Research and Early-warning (CASCIRE), Chinese Academy of Sciences, Beijing 100101, China
| | - Jianxun Qi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Feng Gao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
| | - George F Gao
- Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China; CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China; School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China; CAS Center for Influenza Research and Early-warning (CASCIRE), Chinese Academy of Sciences, Beijing 100101, China; Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Beijing 102206, China.
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25
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Reovirus Neurotropism and Virulence Are Dictated by Sequences in the Head Domain of the Viral Attachment Protein. J Virol 2018; 92:JVI.00974-18. [PMID: 30209169 DOI: 10.1128/jvi.00974-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 09/04/2018] [Indexed: 11/20/2022] Open
Abstract
Viral capsid components that bind cellular receptors mediate critical functions in viral tropism and disease pathogenesis. Mammalian orthoreoviruses (reoviruses) spread systemically in newborn mice to cause serotype-specific disease in the central nervous system (CNS). Serotype 1 (T1) reovirus infects ependymal cells to cause nonlethal hydrocephalus, whereas serotype 3 (T3) reovirus infects neurons to cause fulminant and lethal encephalitis. This serotype-dependent difference in tropism and concomitant disease is attributed to the σ1 viral attachment protein, which is composed of head, body, and tail domains. To identify σ1 sequences that contribute to tropism for specific cell types in the CNS, we engineered a panel of viruses expressing chimeric σ1 proteins in which discrete σ1 domains have been reciprocally exchanged. Parental and chimeric σ1 viruses were compared for replication, tropism, and disease induction following intracranial inoculation of newborn mice. Viruses expressing T1 σ1 head sequences infect the ependyma, produce relatively lower titers in the brain, and do not cause significant disease. In contrast, viruses expressing T3 σ1 head sequences efficiently infect neurons, replicate to relatively higher titers in the brain, and cause a lethal encephalitis. Additionally, T3 σ1 head-expressing viruses display enhanced infectivity of cultured primary cortical neurons compared with T1 σ1 head-expressing viruses. These results indicate that T3 σ1 head domain sequences promote infection of neurons, likely by interaction with a neuron-specific receptor, and dictate tropism in the CNS and induction of encephalitis.IMPORTANCE Viral encephalitis is a serious and often life-threatening inflammation of the brain. Mammalian orthoreoviruses are promising oncolytic therapeutics for humans but establish virulent, serotype-dependent disease in the central nervous system (CNS) of many young mammals. Serotype 1 reoviruses infect ependymal cells and produce hydrocephalus, whereas serotype 3 reoviruses infect neurons and cause encephalitis. Reovirus neurotropism is hypothesized to be dictated by the filamentous σ1 viral attachment protein. However, it is not apparent how this protein mediates disease. We discovered that sequences forming the most virion-distal domain of T1 and T3 σ1 coordinate infection of either ependyma or neurons, respectively, leading to mutually exclusive patterns of tropism and disease in the CNS. These studies contribute new knowledge about how reoviruses target cells for infection in the brain and inform the rational design of improved oncolytic therapies to mitigate difficult-to-treat tumors of the CNS.
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26
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Abstract
Sialic acid-based glycoconjugates cover the surfaces of many different cell types, defining key properties of the cell surface such as overall charge or likely interaction partners. Because of this prominence, sialic acids play prominent roles in mediating attachment and entry to viruses belonging to many different families. In this review, we first describe how interactions between viruses and sialic acid-based glycan structures can be identified and characterized using a range of techniques. We then highlight interactions between sialic acids and virus capsid proteins in four different viruses, and discuss what these interactions have taught us about sialic acid engagement and opportunities to interfere with binding.
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Affiliation(s)
- Bärbel S Blaum
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Thilo Stehle
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany; Vanderbilt University School of Medicine, Nashville, TN, United States
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27
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Protein Mismatches Caused by Reassortment Influence Functions of the Reovirus Capsid. J Virol 2018; 92:JVI.00858-18. [PMID: 30068646 DOI: 10.1128/jvi.00858-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 07/26/2018] [Indexed: 12/22/2022] Open
Abstract
Following attachment to host receptors via σ1, reovirus particles are endocytosed and disassembled to generate infectious subvirion particles (ISVPs). ISVPs undergo conformational changes to form ISVP*, releasing σ1 and membrane-targeting peptides from the viral μ1 protein. ISVP* formation is required for delivery of the viral core into the cytoplasm for replication. We characterized the properties of T3DF/T3DCS1, an S1 gene monoreassortant between two laboratory isolates of prototype reovirus strain T3D: T3DF and T3DC T3DF/T3DCS1 is poorly infectious. This deficiency is a consequence of inefficient encapsidation of S1-encoded σ1 on T3DF/T3DCS1 virions. Additionally, compared to T3DF, T3DF/T3DCS1 undergoes ISVP-to-ISVP* conversion more readily, revealing an unexpected role for σ1 in regulating ISVP* formation. The σ1 protein is held within turrets formed by the λ2 protein. To test if the altered properties of T3DF/T3DCS1 are due to a mismatch between σ1 and λ2 proteins from T3DF and T3DC, properties of T3DF/T3DCL2 and T3DF/T3DCS1L2, which express a T3DC-derived λ2, were compared. The presence of T3DC λ2 allowed more efficient σ1 incorporation, producing particles that exhibit T3DF-like infectivity. Compared to T3DF, T3DF/T3DCL2 prematurely converts to ISVP*, uncovering a role for λ2 in regulating ISVP* formation. Importantly, a virus with matching σ1 and λ2 displayed a more regulated conversion to ISVP* than either T3DF/T3DCS1 or T3DF/T3DCL2. In addition to identifying new regulators of ISVP* formation, our results highlight that protein mismatches produced by reassortment can alter virus assembly and thereby influence subsequent functions of the virus capsid.IMPORTANCE Cells coinfected with viruses that possess a multipartite or segmented genome reassort to produce progeny viruses that contain a combination of gene segments from each parent. Reassortment places new pairs of genes together, generating viruses in which mismatched proteins must function together. To test if such forced pairing of proteins that form the virus shell or capsid alters the function of the particle, we investigated properties of reovirus variants in which the σ1 attachment protein and the λ2 protein that anchors σ1 on the particle are mismatched. Our studies demonstrate that a σ1-λ2 mismatch produces particles with lower levels of encapsidated σ1, consequently decreasing virus attachment and infectivity. The mismatch between σ1 and λ2 also altered the capacity of the viral capsid to undergo conformational changes required for cell entry. These studies reveal new functions of reovirus capsid proteins and illuminate both predictable and novel implications of reassortment.
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28
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Gaber A, Kim SJ, Kaake RM, Benčina M, Krogan N, Šali A, Pavšič M, Lenarčič B. EpCAM homo-oligomerization is not the basis for its role in cell-cell adhesion. Sci Rep 2018; 8:13269. [PMID: 30185875 PMCID: PMC6125409 DOI: 10.1038/s41598-018-31482-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 08/20/2018] [Indexed: 01/01/2023] Open
Abstract
Cell-surface tumor marker EpCAM plays a key role in proliferation, differentiation and adhesion processes in stem and epithelial cells. It is established as a cell-cell adhesion molecule, forming intercellular interactions through homophilic association. However, the mechanism by which such interactions arise has not yet been fully elucidated. Here, we first show that EpCAM monomers do not associate into oligomers that would resemble an inter-cellular homo-oligomer, capable of mediating cell-cell adhesion, by using SAXS, XL-MS and bead aggregation assays. Second, we also show that EpCAM forms stable dimers on the surface of a cell with pre-formed cell-cell contacts using FLIM-FRET; however, no inter-cellular homo-oligomers were detectable. Thus, our study provides clear evidence that EpCAM indeed does not function as a homophilic cell adhesion molecule and therefore calls for a significant revision of its role in both normal and cancerous tissues. In the light of this, we strongly support the previously suggested name Epithelial Cell Activating Molecule instead of the Epithelial Cell Adhesion Molecule.
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Affiliation(s)
- Aljaž Gaber
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Ljubljana, SI 1000, Slovenia
| | - Seung Joong Kim
- Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, 1700 4th Street, Suite 503B, San Francisco, CA, 94158, USA
| | - Robyn M Kaake
- J. David Gladstone Institutes, San Francisco, CA, 94158, USA
| | - Mojca Benčina
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, SI 1000, Slovenia
| | - Nevan Krogan
- J. David Gladstone Institutes, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute, QBI, Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Andrej Šali
- Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, 1700 4th Street, Suite 503B, San Francisco, CA, 94158, USA
| | - Miha Pavšič
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Ljubljana, SI 1000, Slovenia.
| | - Brigita Lenarčič
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Ljubljana, SI 1000, Slovenia.
- Department of Biochemistry, Molecular and Structural Biology, Institute Jožef Stefan, Jamova 39, Ljubljana, SI 1000, Slovenia.
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29
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Maginnis MS. Virus-Receptor Interactions: The Key to Cellular Invasion. J Mol Biol 2018; 430:2590-2611. [PMID: 29924965 PMCID: PMC6083867 DOI: 10.1016/j.jmb.2018.06.024] [Citation(s) in RCA: 184] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 06/04/2018] [Accepted: 06/08/2018] [Indexed: 11/05/2022]
Abstract
Virus–receptor interactions play a key regulatory role in viral host range, tissue tropism, and viral pathogenesis. Viruses utilize elegant strategies to attach to one or multiple receptors, overcome the plasma membrane barrier, enter, and access the necessary host cell machinery. The viral attachment protein can be viewed as the “key” that unlocks host cells by interacting with the “lock”—the receptor—on the cell surface, and these lock-and-key interactions are critical for viruses to successfully invade host cells. Many common themes have emerged in virus–receptor utilization within and across virus families demonstrating that viruses often target particular classes of molecules in order to mediate these events. Common viral receptors include sialylated glycans, cell adhesion molecules such as immunoglobulin superfamily members and integrins, and phosphatidylserine receptors. The redundancy in receptor usage suggests that viruses target particular receptors or “common locks” to take advantage of their cellular function and also suggests evolutionary conservation. Due to the importance of initial virus interactions with host cells in viral pathogenesis and the redundancy in viral receptor usage, exploitation of these strategies would be an attractive target for new antiviral therapeutics. Viral receptors are key regulators of host range, tissue tropism, and viral pathogenesis. Many viruses utilize common viral receptors including sialic acid, cell adhesion molecules such as immunoglobulin superfamily members and integrins, and phosphatidylserine receptors. Detailed molecular interactions between viruses and receptors have been defined through elegant biochemical analyses including glycan array screens, structural–functional analyses, and cell-based approaches providing tremendous insights into these initial events in viral infection. Commonalities in virus–receptor interactions present promising targets for the development of broad-spectrum antiviral therapies.
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Affiliation(s)
- Melissa S Maginnis
- Department of Molecular and Biomedical Sciences, The University of Maine, Orono, ME 04469-5735, USA.
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30
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Guven-Maiorov E, Tsai CJ, Ma B, Nussinov R. Prediction of Host-Pathogen Interactions for Helicobacter pylori by Interface Mimicry and Implications to Gastric Cancer. J Mol Biol 2017; 429:3925-3941. [PMID: 29106933 PMCID: PMC7906438 DOI: 10.1016/j.jmb.2017.10.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 10/16/2017] [Accepted: 10/16/2017] [Indexed: 02/07/2023]
Abstract
There is a strong correlation between some pathogens and certain cancer types. One example is Helicobacter pylori and gastric cancer. Exactly how they contribute to host tumorigenesis is, however, a mystery. Pathogens often interact with the host through proteins. To subvert defense, they may mimic host proteins at the sequence, structure, motif, or interface levels. Interface similarity permits pathogen proteins to compete with those of the host for a target protein and thereby alter the host signaling. Detection of host-pathogen interactions (HPIs) and mapping the re-wired superorganism HPI network-with structural details-can provide unprecedented clues to the underlying mechanisms and help therapeutics. Here, we describe the first computational approach exploiting solely interface mimicry to model potential HPIs. Interface mimicry can identify more HPIs than sequence or complete structural similarity since it appears more common than the other mimicry types. We illustrate the usefulness of this concept by modeling HPIs of H. pylori to understand how they modulate host immunity, persist lifelong, and contribute to tumorigenesis. H. pylori proteins interfere with multiple host pathways as they target several host hub proteins. Our results help illuminate the structural basis of resistance to apoptosis, immune evasion, and loss of cell junctions seen in H. pylori-infected host cells.
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Affiliation(s)
- Emine Guven-Maiorov
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
| | - Chung-Jung Tsai
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
| | - Buyong Ma
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
| | - Ruth Nussinov
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA; Sackler Institute of Molecular Medicine, Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
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31
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Berger AK, Yi H, Kearns DB, Mainou BA. Bacteria and bacterial envelope components enhance mammalian reovirus thermostability. PLoS Pathog 2017; 13:e1006768. [PMID: 29211815 PMCID: PMC5734793 DOI: 10.1371/journal.ppat.1006768] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 12/18/2017] [Accepted: 11/23/2017] [Indexed: 12/24/2022] Open
Abstract
Enteric viruses encounter diverse environments as they migrate through the gastrointestinal tract to infect their hosts. The interaction of eukaryotic viruses with members of the host microbiota can greatly impact various aspects of virus biology, including the efficiency with which viruses can infect their hosts. Mammalian orthoreovirus, a human enteric virus that infects most humans during childhood, is negatively affected by antibiotic treatment prior to infection. However, it is not known how components of the host microbiota affect reovirus infectivity. In this study, we show that reovirus virions directly interact with Gram positive and Gram negative bacteria. Reovirus interaction with bacterial cells conveys enhanced virion thermostability that translates into enhanced attachment and infection of cells following an environmental insult. Enhanced virion thermostability was also conveyed by bacterial envelope components lipopolysaccharide (LPS) and peptidoglycan (PG). Lipoteichoic acid and N-acetylglucosamine-containing polysaccharides enhanced virion stability in a serotype-dependent manner. LPS and PG also enhanced the thermostability of an intermediate reovirus particle (ISVP) that is associated with primary infection in the gut. Although LPS and PG alter reovirus thermostability, these bacterial envelope components did not affect reovirus utilization of its proteinaceous cellular receptor junctional adhesion molecule-A or cell entry kinetics. LPS and PG also did not affect the overall number of reovirus capsid proteins σ1 and σ3, suggesting their effect on virion thermostability is not mediated through altering the overall number of major capsid proteins on the virus. Incubation of reovirus with LPS and PG did not significantly affect the neutralizing efficiency of reovirus-specific antibodies. These data suggest that bacteria enhance reovirus infection of the intestinal tract by enhancing the thermal stability of the reovirus particle at a variety of temperatures through interactions between the viral particle and bacterial envelope components.
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Affiliation(s)
- Angela K. Berger
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Children’s Healthcare of Atlanta, Atlanta, Georgia, United States of America
| | - Hong Yi
- Robert P. Apkarian Integrated Electron Microscopy Core, Emory University, Atlanta, Georgia, United States of America
| | - Daniel B. Kearns
- Department of Biology, Indiana University, Bloomington, Indiana, United States of America
| | - Bernardo A. Mainou
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Children’s Healthcare of Atlanta, Atlanta, Georgia, United States of America
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32
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Sutherland DM, Aravamudhan P, Dermody TS. An Orchestra of Reovirus Receptors: Still Searching for the Conductor. Adv Virus Res 2017; 100:223-246. [PMID: 29551138 DOI: 10.1016/bs.aivir.2017.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Viruses are constantly engaged in a molecular arms race with the host, where efficient and tactical use of cellular receptors benefits critical steps in infection. Receptor use dictates initiation, establishment, and spread of viral infection to new tissues and hosts. Mammalian orthoreoviruses (reoviruses) are pervasive pathogens that use multiple receptors to overcome protective host barriers to disseminate from sites of initial infection and cause disease in young mammals. In particular, reovirus invades the central nervous system (CNS) with serotype-dependent tropism and disease. A single viral gene, encoding the attachment protein σ1, segregates with distinct patterns of CNS injury. Despite the identification and characterization of several reovirus receptors, host factors that dictate tropism via interaction with σ1 remain undefined. Here, we summarize the state of the reovirus receptor field and discuss open questions toward understanding how the reovirus attachment protein dictates CNS tropism.
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Affiliation(s)
| | | | - Terence S Dermody
- University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.
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Grass carp reovirus-GD108 fiber protein is involved in cell attachment. Virus Genes 2017; 53:613-622. [PMID: 28550501 DOI: 10.1007/s11262-017-1467-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 05/15/2017] [Indexed: 10/19/2022]
Abstract
Viral attachment to specific host receptors is the first step in viral infection and serves an essential function in the selection of target cells. In this study, structure analysis, neutralization assays, and cell attachment assays were carried out to evaluate the cell attachment functions of the outer capsid fiber protein of grass carp reovirus GD108 strain (GCRV-GD108). The GCRV-GD108 fiber protein contained 512 amino acids encoded by S7 segment and shared sequence similarities with mammalian reovirus cell attachment protein σ1 and adenovirus fiber. Structural analyses predicted the presence of a coiled-coil tail domain, three adenoviral shafts in the body domain, and a globular head domain, similar to other fiber proteins. Neutralization assays showed that polyclonal antibodies against the fiber protein could prevent viral infection in both fish and grass carp snout fibroblast cells (PSF), suggesting that the recombinant fiber protein could induce neutralized antibodies against GCRV-GD108. Cell attachment assays showed that recombinant fiber protein could bind to PSF cells, demonstrating that the fiber protein functioned as the cell attachment protein in GCRV-GD108. These results provided the basis for further studies of the pathogenesis of grass carp reovirus.
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Su L, Xu C, Cheng C, Lei C, Sun X. MTase Domain of Dendrolimus punctatus cypovirus VP3 Mediates Virion Attachment and Interacts with Host ALP Protein. Viruses 2017; 9:v9040066. [PMID: 28368302 PMCID: PMC5408672 DOI: 10.3390/v9040066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 03/21/2017] [Accepted: 03/23/2017] [Indexed: 12/15/2022] Open
Abstract
Dendrolimus punctatus cypovirus (DpCPV) is an important pathogen of D. punctatus, but little is known about the mechanisms of DpCPV infection. Here, we investigated the effects of VP3, VP4 and VP5 structural proteins on the viral invasion. Both the C-terminal of VP3 (methyltransferase (MTase) domain) and VP4 (A-spike) bound to Spodoptera exigua midgut brush border membrane vesicles (BBMVs) in a dose-dependent manner, and the binding was inhibited by purified DpCPV virions. Importantly, anti-MTase and anti-VP4 antibodies inhibited viral binding to S. exigua BBMVs. Using far-Western blots, a 65 kDa protein in Bombyx mori BBMVs, identified as alkaline phosphatase protein (BmALP) by mass spectrometry, specifically interacted with DpCPV MTase. The interaction between MTase and BmALP was verified by co-immunoprecipitation in vitro. Pretreatment of B. mori BBMVs with an anti-ALP antibody or incubation of DpCPV virions with prokaryotically expressed BmALP reduced viral attachment. Additionally, BmALP inhibited DpCPV infection in S. exigua larvae. Our data provide evidence that the MTase domain and A-spike function as viral attachment proteins during the DpCPV infection process, and ALP is the ligand that interacts with DpCPV via the MTase domain. These results augment our understanding of the mechanisms used by cypoviruses to enter their hosts.
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Affiliation(s)
- Lan Su
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Congrui Xu
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Chuangang Cheng
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
| | - Chengfeng Lei
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
| | - Xiulian Sun
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
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Zhang A, He L, Wang Y. Prediction of GCRV virus-host protein interactome based on structural motif-domain interactions. BMC Bioinformatics 2017; 18:145. [PMID: 28253857 PMCID: PMC5335770 DOI: 10.1186/s12859-017-1500-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 01/27/2017] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Grass carp hemorrhagic disease, caused by grass carp reovirus (GCRV), is the most fatal causative agent in grass carp aquaculture. Protein-protein interactions between virus and host are one avenue through which GCRV can trigger infection and induce disease. Experimental approaches for the detection of host-virus interactome have many inherent limitations, and studies on protein-protein interactions between GCRV and its host remain rare. RESULTS In this study, based on known motif-domain interaction information, we systematically predicted the GCRV virus-host protein interactome by using motif-domain interaction pair searching strategy. These proteins derived from different domain families and were predicted to interact with different motif patterns in GCRV. JAM-A protein was successfully predicted to interact with motifs of GCRV Sigma1-like protein, and shared the similar binding mode compared with orthoreovirus. Differentially expressed genes during GCRV infection process were extracted and mapped to our predicted interactome, the overlapped genes displayed different tissue expression distributions on the whole, the overall expression level in intestinal is higher than that of other three tissues, which may suggest that the functions of these genes are more active in intestinal. Function annotation and pathway enrichment analysis revealed that the host targets were largely involved in signaling pathway and immune pathway, such as interferon-gamma signaling pathway, VEGF signaling pathway, EGF receptor signaling pathway, B cell activation, and T cell activation. CONCLUSIONS Although the predicted PPIs may contain some false positives due to limited data resource and poor research background in non-model species, the computational method still provide reasonable amount of interactions, which can be further validated by high throughput experiments. The findings of this work will contribute to the development of system biology for GCRV infectious diseases, and help guide the identification of novel receptors of GCRV in its host.
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Affiliation(s)
- Aidi Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Libo He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Yaping Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
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Fan Y, Guo YR, Yuan W, Zhou Y, Holt MV, Wang T, Demeler B, Young NL, Zhong W, Tao YJ. Structure of a pentameric virion-associated fiber with a potential role in Orsay virus entry to host cells. PLoS Pathog 2017; 13:e1006231. [PMID: 28241071 PMCID: PMC5344674 DOI: 10.1371/journal.ppat.1006231] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 03/09/2017] [Accepted: 02/10/2017] [Indexed: 11/25/2022] Open
Abstract
Despite the wide use of Caenorhabditis elegans as a model organism, the first virus naturally infecting this organism was not discovered until six years ago. The Orsay virus and its related nematode viruses have a positive-sense RNA genome, encoding three proteins: CP, RdRP, and a novel δ protein that shares no homology with any other proteins. δ can be expressed either as a free δ or a CP-δ fusion protein by ribosomal frameshift, but the structure and function of both δ and CP-δ remain unknown. Using a combination of electron microscopy, X-ray crystallography, computational and biophysical analyses, here we show that the Orsay δ protein forms a ~420-Å long, pentameric fiber with an N-terminal α-helical bundle, a β-stranded filament in the middle, and a C-terminal head domain. The pentameric nature of the δ fiber has been independently confirmed by both mass spectrometry and analytical ultracentrifugation. Recombinant Orsay capsid containing CP-δ shows protruding long fibers with globular heads at the distal end. Mutant viruses with disrupted CP-δ fibers were generated by organism-based reverse genetics. These viruses were found to be either non-viable or with poor infectivity according to phenotypic and qRT-PCR analyses. Furthermore, addition of purified δ proteins to worm culture greatly reduced Orsay infectivity in a sequence-specific manner. Based on the structure resemblance between the Orsay CP-δ fiber and the fibers from reovirus and adenovirus, we propose that CP-δ functions as a cell attachment protein to mediate Orsay entry into worm intestine cells.
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Affiliation(s)
- Yanlin Fan
- Department of BioSciences, Rice University, MS-140, Houston, Texas, United States of America
| | - Yusong R. Guo
- Department of BioSciences, Rice University, MS-140, Houston, Texas, United States of America
| | - Wang Yuan
- Department of BioSciences, Rice University, MS-140, Houston, Texas, United States of America
| | - Ying Zhou
- Department of BioSciences, Rice University, MS-140, Houston, Texas, United States of America
| | - Matthew V. Holt
- Verna & Marrs McLean Department of Biochemistry & Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, United States of America
| | - Tao Wang
- Verna & Marrs McLean Department of Biochemistry & Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, United States of America
| | - Borries Demeler
- The University of Texas Health Science Center at San Antonio, Department of Biochemistry, MC 7760, 7703 Floyd Curl Drive, San Antonio, Texas, United States of America
| | - Nicolas L. Young
- Verna & Marrs McLean Department of Biochemistry & Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, United States of America
- Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, United States of America
| | - Weiwei Zhong
- Department of BioSciences, Rice University, MS-140, Houston, Texas, United States of America
| | - Yizhi J. Tao
- Department of BioSciences, Rice University, MS-140, Houston, Texas, United States of America
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Structural Insights into Reovirus σ1 Interactions with Two Neutralizing Antibodies. J Virol 2017; 91:JVI.01621-16. [PMID: 27928010 DOI: 10.1128/jvi.01621-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 11/29/2016] [Indexed: 01/09/2023] Open
Abstract
Reovirus attachment protein σ1 engages glycan receptors and junctional adhesion molecule-A (JAM-A) and is thought to undergo a conformational change during the proteolytic disassembly of virions to infectious subvirion particles (ISVPs) that accompanies cell entry. The σ1 protein is also the primary target of neutralizing antibodies. Here, we present a structural and functional characterization of two neutralizing antibodies that target σ1 of serotype 1 (T1) and serotype 3 (T3) reoviruses. The crystal structures revealed that each antibody engages its cognate σ1 protein within the head domain via epitopes distinct from the JAM-A-binding site. Surface plasmon resonance and cell-binding assays indicated that both antibodies likely interfere with JAM-A engagement by steric hindrance. To define the interplay between the carbohydrate receptor and antibody binding, we conducted hemagglutination inhibition assays using virions and ISVPs. The glycan-binding site of T1 σ1 is located in the head domain and is partly occluded by the bound Fab in the crystal structure. The T1-specific antibody inhibited hemagglutination by virions and ISVPs, probably via direct interference with glycan engagement. In contrast to T1 σ1, the carbohydrate-binding site of T3 σ1 is located in the tail domain, distal to the antibody epitope. The T3-specific antibody inhibited hemagglutination by T3 virions but not ISVPs, indicating that the antibody- and glycan-binding sites in σ1 are in closer spatial proximity on virions than on ISVPs. Our results provide direct evidence for a structural rearrangement of σ1 during virion-to-ISVP conversion and contribute new information about the mechanisms of antibody-mediated neutralization of reovirus. IMPORTANCE Virus attachment proteins mediate binding to host cell receptors, serve critical functions in cell and tissue tropism, and are often targeted by the neutralizing antibody response. The structural investigation of antibody-antigen complexes can provide valuable information for understanding the molecular basis of virus neutralization. Studies with enveloped viruses, such as HIV and influenza virus, have helped to define sites of vulnerability and guide vaccination strategies. By comparison, less is known about antibody binding to nonenveloped viruses. Here, we structurally investigated two neutralizing antibodies that bind the attachment protein σ1 of reovirus. Furthermore, we characterized the neutralization efficiency, the binding affinity for σ1, and the effect of the antibodies on reovirus receptor engagement. Our analysis defines reovirus interactions with two neutralizing antibodies, allows us to propose a mechanism by which they block virus infection, and provides evidence for a conformational change in the σ1 protein during viral cell entry.
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Reovirus μ1 Protein Affects Infectivity by Altering Virus-Receptor Interactions. J Virol 2016; 90:10951-10962. [PMID: 27681135 DOI: 10.1128/jvi.01843-16] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 09/22/2016] [Indexed: 01/04/2023] Open
Abstract
Proteins that form the reovirus outer capsid play an active role in the entry of reovirus into host cells. Among these, the σ1 protein mediates attachment of reovirus particles to host cells via interaction with cell surface glycans or the proteinaceous receptor junctional adhesion molecule A (JAM-A). The μ1 protein functions to penetrate the host cell membrane to allow delivery of the genome-containing viral core particle into the cytoplasm to initiate viral replication. We demonstrate that a reassortant virus that expresses the M2 gene-encoded μ1 protein derived from prototype strain T3D in an otherwise prototype T1L background (T1L/T3DM2) infects cells more efficiently than parental T1L. Unexpectedly, the enhancement in infectivity of T1L/T3DM2 is due to its capacity to attach to cells more efficiently. We present genetic data implicating the central region of μ1 in altering the cell attachment property of reovirus. Our data indicate that the T3D μ1-mediated enhancement in infectivity of T1L is dependent on the function of σ1 and requires the expression of JAM-A. We also demonstrate that T1L/T3DM2 utilizes JAM-A more efficiently than T1L. These studies revealed a previously unknown relationship between two nonadjacent reovirus outer capsid proteins, σ1 and μ1. IMPORTANCE How reovirus attaches to host cells has been extensively characterized. Attachment of reovirus to host cells is mediated by the σ1 protein, and properties of σ1 influence the capacity of reovirus to target specific host tissues and produce disease. Here, we present new evidence indicating that the cell attachment properties of σ1 are influenced by the nature of μ1, a capsid protein that does not physically interact with σ1. These studies could explain the previously described role for μ1 in influencing reovirus pathogenesis. These studies are also of broader significance because they highlight an example of how genetic reassortment between virus strains could produce phenotypes that are distinct from those of either parent.
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Engineering Recombinant Reoviruses To Display gp41 Membrane-Proximal External-Region Epitopes from HIV-1. mSphere 2016; 1:mSphere00086-16. [PMID: 27303748 PMCID: PMC4888892 DOI: 10.1128/msphere.00086-16] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/25/2016] [Indexed: 12/30/2022] Open
Abstract
Vaccines to protect against HIV-1, the causative agent of AIDS, are not approved for use. Antibodies that neutralize genetically diverse strains of HIV-1 bind to discrete regions of the envelope glycoproteins, including the gp41 MPER. We engineered recombinant reoviruses that displayed MPER epitopes in attachment protein σ1 (REO-MPER vectors). The REO-MPER vectors replicated with wild-type efficiency, were genetically stable, and retained native antigenicity. However, we did not detect HIV-1-specific immune responses following inoculation of the REO-MPER vectors into small animals. This work provides proof of principle for engineering reovirus to express antigenic epitopes and illustrates the difficulty in eliciting MPER-specific immune responses. The gp41 membrane-proximal external region (MPER) is a target for broadly neutralizing antibody responses against human immunodeficiency virus type 1 (HIV-1). However, replication-defective virus vaccines currently under evaluation in clinical trials do not efficiently elicit MPER-specific antibodies. Structural modeling suggests that the MPER forms an α-helical coiled coil that is required for function and immunogenicity. To maintain the native MPER conformation, we used reverse genetics to engineer replication-competent reovirus vectors that displayed MPER sequences in the α-helical coiled-coil tail domain of viral attachment protein σ1. Sequences in reovirus strain type 1 Lang (T1L) σ1 were exchanged with sequences encoding HIV-1 strain Ba-L MPER epitope 2F5 or the entire MPER. Individual 2F5 or MPER substitutions were introduced at virion-proximal or virion-distal sites in the σ1 tail. Recombinant reoviruses containing heterologous HIV-1 sequences were viable and produced progeny yields comparable to those with wild-type virus. HIV-1 sequences were retained following 10 serial passages in cell culture, indicating that the substitutions were genetically stable. Recombinant viruses engineered to display the 2F5 epitope or full-length MPER in σ1 were recognized by purified 2F5 antibody. Inoculation of mice with 2F5-containing vectors or rabbits with 2F5- or MPER-containing vectors elicited anti-reovirus antibodies, but HIV-1-specific antibodies were not detected. Together, these findings indicate that heterologous sequences that form α-helices can functionally replace native sequences in the α-helical tail domain of reovirus attachment protein σ1. However, although these vectors retain native antigenicity, they were not immunogenic, illustrating the difficulty of experimentally inducing immune responses to this essential region of HIV-1. IMPORTANCE Vaccines to protect against HIV-1, the causative agent of AIDS, are not approved for use. Antibodies that neutralize genetically diverse strains of HIV-1 bind to discrete regions of the envelope glycoproteins, including the gp41 MPER. We engineered recombinant reoviruses that displayed MPER epitopes in attachment protein σ1 (REO-MPER vectors). The REO-MPER vectors replicated with wild-type efficiency, were genetically stable, and retained native antigenicity. However, we did not detect HIV-1-specific immune responses following inoculation of the REO-MPER vectors into small animals. This work provides proof of principle for engineering reovirus to express antigenic epitopes and illustrates the difficulty in eliciting MPER-specific immune responses.
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Mateo M, Generous A, Sinn PL, Cattaneo R. Connections matter--how viruses use cell–cell adhesion components. J Cell Sci 2016; 128:431-9. [PMID: 26046138 DOI: 10.1242/jcs.159400] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The epithelium is a highly organized type of animal tissue. Except for blood and lymph vessels, epithelial cells cover the body, line its cavities in single or stratified layers and support exchange between compartments. In addition, epithelia offer to the body a barrier to pathogen invasion. To transit through or to replicate in epithelia, viruses have to face several obstacles, starting from cilia and glycocalyx where they can be neutralized by secreted immunoglobulins. Tight junctions and adherens junctions also prevent viruses to cross the epithelial barrier. However, viruses have developed multiple strategies to blaze their path through the epithelium by utilizing components of cell–cell adhesion structures as receptors. In this Commentary, we discuss how viruses take advantage of the apical junction complex to spread. Whereas some viruses quickly disrupt epithelium integrity, others carefully preserve it and use cell adhesion proteins and their cytoskeletal connections to rapidly spread laterally. This is exemplified by the hidden transmission of enveloped viruses that use nectins as receptors. Finally, several viruses that replicate preferentially in cancer cells are currently used as experimental cancer therapeutics. Remarkably, these viruses use cell adhesion molecules as receptors, probably because--to reach tumors and metastases--ncolytic viruses must efficiently traverse or break epithelia.
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Smith YE, Vellanki SH, Hopkins AM. Dynamic interplay between adhesion surfaces in carcinomas: Cell-cell and cell-matrix crosstalk. World J Biol Chem 2016; 7:64-77. [PMID: 26981196 PMCID: PMC4768125 DOI: 10.4331/wjbc.v7.i1.64] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 09/22/2015] [Accepted: 11/04/2015] [Indexed: 02/05/2023] Open
Abstract
Cell-cell and cell-matrix signaling and communication between adhesion sites involve mechanisms which are required for cellular functions during normal development and homeostasis; however these cellular functions and mechanisms are often deregulated in cancer. Aberrant signaling at cell-cell and cell-matrix adhesion sites often involves downstream mediators including Rho GTPases and tyrosine kinases. This review discusses these molecules as putative mediators of cellular crosstalk between cell-cell and cell-matrix adhesion sites, in addition to their attractiveness as therapeutic targets in cancer. Interestingly, inter-junctional crosstalk mechanisms are frequently typified by the way in which bacterial and viral pathogens opportunistically infect or intoxicate mammalian cells. This review therefore also discusses the concept of learning from pathogen-host interaction studies to better understand coordinated communication between cell-cell and cell-matrix adhesion sites, in addition to highlighting the potential therapeutic usefulness of exploiting pathogens or their products to tap into inter-junctional crosstalk. Taken together, we feel that increased knowledge around mechanisms of cell-cell and cell-matrix adhesion site crosstalk and consequently a greater understanding of their therapeutic targeting offers a unique opportunity to contribute to the emerging molecular revolution in cancer biology.
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Bhella D. The role of cellular adhesion molecules in virus attachment and entry. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140035. [PMID: 25533093 PMCID: PMC4275905 DOI: 10.1098/rstb.2014.0035] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
As obligate intracellular parasites, viruses must traverse the host-cell plasma membrane to initiate infection. This presents a formidable barrier, which they have evolved diverse strategies to overcome. Common to all entry pathways, however, is a mechanism of specific attachment to cell-surface macromolecules or ‘receptors’. Receptor usage frequently defines viral tropism, and consequently, the evolutionary changes in receptor specificity can lead to emergence of new strains exhibiting altered pathogenicity or host range. Several classes of molecules are exploited as receptors by diverse groups of viruses, including, for example, sialic acid moieties and integrins. In particular, many cell-adhesion molecules that belong to the immunoglobulin-like superfamily of proteins (IgSF CAMs) have been identified as viral receptors. Structural analysis of the interactions between viruses and IgSF CAM receptors has not shown binding to specific features, implying that the Ig-like fold may not be key. Both proteinaceous and enveloped viruses exploit these proteins, however, suggesting convergent evolution of this trait. Their use is surprising given the usually occluded position of CAMs on the cell surface, such as at tight junctions. Nonetheless, the reason for their widespread involvement in virus entry most probably originates in their functional rather than structural characteristics.
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Affiliation(s)
- David Bhella
- Medical Research Council-University of Glasgow Centre for Virus Research, Sir Michael Stoker Building, Garscube Campus, 464 Bearsden Road, Glasgow G61 1QH, UK
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Kemp V, Hoeben RC, van den Wollenberg DJM. Exploring Reovirus Plasticity for Improving Its Use as Oncolytic Virus. Viruses 2015; 8:E4. [PMID: 26712782 PMCID: PMC4728564 DOI: 10.3390/v8010004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 12/04/2015] [Accepted: 12/15/2015] [Indexed: 12/13/2022] Open
Abstract
Reoviruses are non-enveloped viruses with a segmented double stranded RNA genome. In humans, they are not associated with serious disease. Human reoviruses exhibit an inherent preference to replicate in tumor cells, which makes them ideally suited for use in oncolytic virotherapies. Their use as anti-cancer agent has been evaluated in several clinical trials, which revealed that intra-tumoral and systemic delivery of reoviruses are well tolerated. Despite evidence of anti-tumor effects, the efficacy of reovirus in anti-cancer monotherapy needs to be further enhanced. The opportunity to treat both the primary tumor as well as metastases makes systemic delivery a preferred administration route. Several pre-clinical studies have been conducted to address the various hurdles connected to systemic delivery of reoviruses. The majority of those studies have been done in tumor-bearing immune-deficient murine models. This thwarts studies on the impact of the contribution of the immune system to the tumor cell eradication. This review focuses on key aspects of the reovirus/host-cell interactions and the methods that are available to modify the virus to alter these interactions. These aspects are discussed with a focus on improving the reovirus' antitumor efficacy.
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Affiliation(s)
- Vera Kemp
- Department of Molecular Cell Biology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
| | - Rob C Hoeben
- Department of Molecular Cell Biology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
| | - Diana J M van den Wollenberg
- Department of Molecular Cell Biology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
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Mohamed A, Johnston RN, Shmulevitz M. Potential for Improving Potency and Specificity of Reovirus Oncolysis with Next-Generation Reovirus Variants. Viruses 2015; 7:6251-78. [PMID: 26633466 PMCID: PMC4690860 DOI: 10.3390/v7122936] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Revised: 11/10/2015] [Accepted: 11/18/2015] [Indexed: 12/16/2022] Open
Abstract
Viruses that specifically replicate in tumor over normal cells offer promising cancer therapies. Oncolytic viruses (OV) not only kill the tumor cells directly; they also promote anti-tumor immunotherapeutic responses. Other major advantages of OVs are that they dose-escalate in tumors and can be genetically engineered to enhance potency and specificity. Unmodified wild type reovirus is a propitious OV currently in phase I–III clinical trials. This review summarizes modifications to reovirus that may improve potency and/or specificity during oncolysis. Classical genetics approaches have revealed reovirus variants with improved adaptation towards tumors or with enhanced ability to establish specific steps of virus replication and cell killing among transformed cells. The recent emergence of a reverse genetics system for reovirus has provided novel strategies to fine-tune reovirus proteins or introduce exogenous genes that could promote oncolytic activity. Over the next decade, these findings are likely to generate better-optimized second-generation reovirus vectors and improve the efficacy of oncolytic reotherapy.
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Affiliation(s)
- Adil Mohamed
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2E1, Canada.
| | - Randal N Johnston
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada.
| | - Maya Shmulevitz
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2E1, Canada.
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Singh AK, Berbís MÁ, Ballmann MZ, Kilcoyne M, Menéndez M, Nguyen TH, Joshi L, Cañada FJ, Jiménez-Barbero J, Benkő M, Harrach B, van Raaij MJ. Structure and Sialyllactose Binding of the Carboxy-Terminal Head Domain of the Fibre from a Siadenovirus, Turkey Adenovirus 3. PLoS One 2015; 10:e0139339. [PMID: 26418008 PMCID: PMC4587935 DOI: 10.1371/journal.pone.0139339] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 09/11/2015] [Indexed: 01/16/2023] Open
Abstract
The virulent form of turkey adenovirus 3 (TAdV-3), also known as turkey hemorrhagic enteritis virus (THEV), is an economically important poultry pathogen, while the avirulent form is used as a vaccine. TAdV-3 belongs to the genus Siadenovirus. The carboxy-terminal region of its fibre does not have significant sequence similarity to any other adenovirus fibre heads of known structure. Two amino acid sequence differences between virulent and avirulent TAdV-3 map on the fibre head: where virulent TAdV-3 contains Ile354 and Thr376, avirulent TAdV-3 contains Met354 and Met376. We determined the crystal structures of the trimeric virulent and avirulent TAdV-3 fibre head domains at 2.2 Å resolution. Each monomer contains a beta-sandwich, which, surprisingly, resembles reovirus fibre head more than other adenovirus fibres, although the ABCJ-GHID topology is conserved in all. A beta-hairpin insertion in the C-strand of each trimer subunit embraces its neighbouring monomer. The avirulent and virulent TAdV-3 fibre heads are identical apart from the exact orientation of the beta-hairpin insertion. In vitro, sialyllactose was identified as a ligand by glycan microarray analysis, nuclear magnetic resonance spectroscopy, and crystallography. Its dissociation constant was measured to be in the mM range by isothermal titration calorimetry. The ligand binds to the side of the fibre head, involving amino acids Glu392, Thr419, Val420, Lys421, Asn422, and Gly423 binding to the sialic acid group. It binds slightly more strongly to the avirulent form. We propose that, in vivo, the TAdV-3 fibre may bind a sialic acid-containing cell surface component.
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Affiliation(s)
- Abhimanyu K. Singh
- Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain
| | - M. Álvaro Berbís
- Departamento de Biología Física-Química, Centro de Investigaciones Biológicas (CIB-CSIC), Madrid, Spain
| | - Mónika Z. Ballmann
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Michelle Kilcoyne
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland
- Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Margarita Menéndez
- Departamento de Química Física-Biológica, Instituto de Química Física Rocasolano (IQFR-CSIC) and CIBER de Enfermedades Respiratorias (CIBERES), calle Serrano 119, E-28006 Madrid, Spain
| | - Thanh H. Nguyen
- Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain
| | - Lokesh Joshi
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland
| | - F. Javier Cañada
- Departamento de Biología Física-Química, Centro de Investigaciones Biológicas (CIB-CSIC), Madrid, Spain
| | - Jesús Jiménez-Barbero
- Departamento de Biología Física-Química, Centro de Investigaciones Biológicas (CIB-CSIC), Madrid, Spain
- Centro de Investigación Cooperativa en Biociencias (CIC bioGUNE), Parque Tecnológico de Bizkaia, Derio, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Mária Benkő
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Balázs Harrach
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Mark J. van Raaij
- Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain
- * E-mail:
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Abstract
Tight junctions (TJs) are highly specialized membrane domains involved in many important cellular processes such as the regulation of the passage of ions and macromolecules across the paracellular space and the establishment of cell polarity in epithelial cells. Over the past few years there has been increasing evidence that different components of the TJs can be hijacked by viruses in order to complete their infectious cycle. Viruses from at least nine different families of DNA and RNA viruses have been reported to use TJ proteins in their benefit. For example, TJ proteins such as JAM-A or some members of the claudin family of proteins are used by members of the Reoviridae family and hepatitis C virus as receptors or co-receptors during their entry into their host cells. Reovirus, in addition, takes advantage of the TJ protein Junction Adhesion Molecule-A (JAM-A) to achieve its hematogenous dissemination. Some other viruses are capable of regulating the expression or the localization of TJ proteins to induce cell transformation or to improve the efficiency of their exit process. This review encompasses the importance of TJs for viral entry, replication, dissemination, and egress, and makes a clear statement of the importance of studying these proteins to gain a better understanding of the replication strategies used by viruses that infect epithelial and/or endothelial cells.
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Kwon HJ, Jeong JH, Lee SW, Ryu YB, Jeong HJ, Jung K, Lim JS, Cho KO, Lee WS, Rho MC, Park SJ. In vitro anti-reovirus activity of kuraridin isolated from Sophora flavescens against viral replication and hemagglutination. J Pharmacol Sci 2015; 128:159-69. [PMID: 26076959 PMCID: PMC7172900 DOI: 10.1016/j.jphs.2015.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 04/05/2015] [Accepted: 04/21/2015] [Indexed: 11/22/2022] Open
Abstract
In this study, we evaluated the anti-reovirus activity of kuraridin isolated from the roots of Sophora flavescens. In particular, we focused on whether this property is attributable to direct inhibition of reovirus attachment and/or inhibition of viral replication with the aid of time-of-addition (pre-treatment, simultaneous treatment, and post-treatment) experiments. No significant antiviral activity of kuraridin was detected in the pre-treatment assay. In the simultaneous assay, the 50% effective inhibitory concentrations (EC50) of kuraridin were 15.3–176.9 μM against human type 1–3 reoviruses (HRV1–3) and Korean porcine reovirus (PRV). Kuraridin completely blocked binding of viral sigma 1 protein to sialic acids at concentrations lower than 82.5 μM in the hemagglutination inhibition assay. Moreover, kuraridin inhibited HRV1–3 and PRV viral replication with EC50 values of 14.0–62.0 μM. Quantitative real-time PCR analysis disclosed strong suppression of reovirus RNA synthesis at the late stage (18 h) of virus replication by kuraridin. The viral yields of kuraridin-treated cells were significantly reduced at 24 h post-infection, compared with DMSO-treated cells. Our results collectively suggest that kuraridin inhibits virus adsorption and replication by inhibiting hemagglutination, viral RNA and protein synthesis and virus shedding, supporting its utility as a viable candidate antiviral drug against reoviruses.
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Affiliation(s)
- Hyung-Jun Kwon
- Eco-friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea
| | - Jae-Ho Jeong
- Department of Microbiology, Chonnam National University Medical School, Gwangju 501-746, Republic of Korea
| | - Seung Woong Lee
- Department of Chemistry, Mokwon University, Daejeon 302-729, Republic of Korea
| | - Young Bae Ryu
- Eco-friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea
| | - Hyung Jae Jeong
- Eco-friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea
| | - Kyungsook Jung
- Eco-friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea
| | - Jae Sung Lim
- Department of Biochemistry, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Kyoung-Oh Cho
- Biotherapy Human Resources Center, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, Republic of Korea
| | - Woo Song Lee
- Eco-friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea
| | - Mun-Chual Rho
- Eco-friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea.
| | - Su-Jin Park
- Eco-friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea.
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Weaver EA, Camacho ZT, Hillestad ML, Crosby CM, Turner MA, Guenzel AJ, Fadel HJ, Mercier GT, Barry MA. Mucosal vaccination by adenoviruses displaying reovirus sigma 1. Virology 2015; 482:60-6. [PMID: 25827529 DOI: 10.1016/j.virol.2015.02.050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 02/17/2015] [Accepted: 02/25/2015] [Indexed: 10/23/2022]
Abstract
We developed adenovirus serotype 5 (Ad5) vectors displaying the sigma 1 protein from reovirus as mucosal vaccines. Ad5-sigma retargets to JAM-1 and sialic acid, but has 40-fold reduced gene delivery when compared to Ad5. While weaker at transduction, Ad5-sigma generates stronger T cell responses than Ad5 when used for mucosal immunization. In this work, new Ad5-fiber-sigma vectors were generated by varying the number of fiber β-spiral shaft repeats (R) between the fiber tail and sigma. Increasing chimera length led to decreasing insertion of these proteinsAd5 virions. Ad-R3 and R14 vectors effectively targeted JAM-1 in vitro while R20 did not. When wereused to immunize mice by the intranasal route, Ad5-R3-sigma produced higher serum and vaginal antibody responses than Ad5. These data suggest optimized Ad-sigma vectors may be useful vectors for mucosal vaccination.
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Affiliation(s)
- Eric A Weaver
- Department of Internal Medicine, Division of Infectious Diseases, Translational Immunovirology and Biodefense Program, Mayo Clinic, Rochester, MN 55902, USA
| | - Zenaido T Camacho
- Department of Cell Biology, Department of Natural Sciences, Western New Mexico University, Silver City, NM 88062, USA
| | | | - Catherine M Crosby
- Virology and Gene Therapy Graduate Program, Mayo Clinic, Rochester, MN 55902, USA
| | - Mallory A Turner
- Virology and Gene Therapy Graduate Program, Mayo Clinic, Rochester, MN 55902, USA
| | - Adam J Guenzel
- Virology and Gene Therapy Graduate Program, Mayo Clinic, Rochester, MN 55902, USA
| | - Hind J Fadel
- Virology and Gene Therapy Graduate Program, Mayo Clinic, Rochester, MN 55902, USA
| | - George T Mercier
- Department of Physics, University of Houston, Houston, TX 77004, USA
| | - Michael A Barry
- Department of Internal Medicine, Division of Infectious Diseases, Translational Immunovirology and Biodefense Program, Mayo Clinic, Rochester, MN 55902, USA; Department of Immunology and Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55902, USA.
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49
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Structure of Serotype 1 Reovirus Attachment Protein σ1 in Complex with Junctional Adhesion Molecule A Reveals a Conserved Serotype-Independent Binding Epitope. J Virol 2015; 89:6136-40. [PMID: 25810543 DOI: 10.1128/jvi.00433-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 03/17/2015] [Indexed: 01/02/2023] Open
Abstract
Mammalian orthoreoviruses use glycans and junctional adhesion molecule A (JAM-A) as attachment receptors. We determined the structure of serotype 1 reovirus attachment protein σ1 alone and in complex with JAM-A. Comparison with the structure of serotype 3 reovirus σ1 bound to JAM-A reveals that both σ1 proteins engage JAM-A with similar affinities and via conserved binding epitopes. Thus, σ1-JAM-A interactions are unlikely to explain the differences in pathogenesis displayed by these reovirus serotypes.
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50
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Diminished reovirus capsid stability alters disease pathogenesis and littermate transmission. PLoS Pathog 2015; 11:e1004693. [PMID: 25738608 PMCID: PMC4349883 DOI: 10.1371/journal.ppat.1004693] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 01/21/2015] [Indexed: 01/22/2023] Open
Abstract
Reovirus is a nonenveloped mammalian virus that provides a useful model system for studies of viral infections in the young. Following internalization into host cells, the outermost capsid of reovirus virions is removed by endosomal cathepsin proteases. Determinants of capsid disassembly kinetics reside in the viral σ3 protein. However, the contribution of capsid stability to reovirus-induced disease is unknown. In this study, we found that mice inoculated intramuscularly with a serotype 3 reovirus containing σ3-Y354H, a mutation that reduces viral capsid stability, succumbed at a higher rate than those infected with wild-type virus. At early times after inoculation, σ3-Y354H virus reached higher titers than wild-type virus at several sites within the host. Animals inoculated perorally with a serotype 1 reassortant reovirus containing σ3-Y354H developed exaggerated myocarditis accompanied by elaboration of pro-inflammatory cytokines. Surprisingly, unchallenged littermates of mice infected with σ3-Y354H virus displayed higher titers in the intestine, heart, and brain than littermates of mice inoculated with wild-type virus. Together, these findings suggest that diminished capsid stability enhances reovirus replication, dissemination, lethality, and host-to-host spread, establishing a new virulence determinant for nonenveloped viruses. Following attachment and internalization, viruses disassemble to complete the entry process, establish infection, and cause disease. Viral capsid stability balances on a fulcrum, as viruses must be sufficiently stable in the environment to reach the host yet also uncoat efficiently once the target cell barrier has been breached. Reoviruses are useful models to understand the relationship between viral entry and pathogenesis. Residues within reovirus outer-capsid protein σ3 influence capsid stability, but the function of capsid stability in disease pathogenesis was not known. We found that serotype 1 and serotype 3 reovirus variants with diminished capsid stability attributable to a single amino change in σ3 displayed enhanced lethality in newborn mice following peroral and intramuscular inoculation, respectively. In the serotype 1 background, this variant caused increased damage to cardiac tissue and increased elaboration of inflammatory mediators in comparison to wild-type virus. Remarkably, diminished capsid stability also enhanced the spread of virus between inoculated and uninoculated littermates. Taken together, these findings define a new virulence determinant for reovirus and shed light on general principles of viral pathogenesis for nonenveloped viruses.
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