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Coulibaly F. Structure of the poxvirus core. Nat Struct Mol Biol 2024; 31:1001-1003. [PMID: 38890551 DOI: 10.1038/s41594-024-01331-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Affiliation(s)
- Fasséli Coulibaly
- Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia.
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2
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Datler J, Hansen JM, Thader A, Schlögl A, Bauer LW, Hodirnau VV, Schur FKM. Multi-modal cryo-EM reveals trimers of protein A10 to form the palisade layer in poxvirus cores. Nat Struct Mol Biol 2024; 31:1114-1123. [PMID: 38316877 PMCID: PMC11257981 DOI: 10.1038/s41594-023-01201-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 12/06/2023] [Indexed: 02/07/2024]
Abstract
Poxviruses are among the largest double-stranded DNA viruses, with members such as variola virus, monkeypox virus and the vaccination strain vaccinia virus (VACV). Knowledge about the structural proteins that form the viral core has remained sparse. While major core proteins have been annotated via indirect experimental evidence, their structures have remained elusive and they could not be assigned to individual core features. Hence, which proteins constitute which layers of the core, such as the palisade layer and the inner core wall, has remained enigmatic. Here we show, using a multi-modal cryo-electron microscopy (cryo-EM) approach in combination with AlphaFold molecular modeling, that trimers formed by the cleavage product of VACV protein A10 are the key component of the palisade layer. This allows us to place previously obtained descriptions of protein interactions within the core wall into perspective and to provide a detailed model of poxvirus core architecture. Importantly, we show that interactions within A10 trimers are likely generalizable over members of orthopox- and parapoxviruses.
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Affiliation(s)
- Julia Datler
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Jesse M Hansen
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Andreas Thader
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Alois Schlögl
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Lukas W Bauer
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | | | - Florian K M Schur
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria.
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3
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Urquiza J, Cuesta-Geijo MÁ, García-Dorival I, Fernández Ó, del Puerto A, Díaz JF, Alonso C. Identification of a Potential Entry-Fusion Complex Based on Sequence Homology of African Swine Fever and Vaccinia Virus. Viruses 2024; 16:349. [PMID: 38543715 PMCID: PMC10975062 DOI: 10.3390/v16030349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 02/20/2024] [Accepted: 02/22/2024] [Indexed: 05/23/2024] Open
Abstract
African swine fever virus (ASFV) belongs to the family of Asfarviridae, part of the group of nucleocytoplasmic large DNA viruses (NCLDV). Little is known about the internalization of ASFV in the host cell and the fusion membrane events that take place at early stages of the infection. Poxviruses, also members of the NCLDV and represented by vaccinia virus (VACV), are large, enveloped, double-stranded DNA viruses. Poxviruses were considered unique in having an elaborate entry-fusion complex (EFC) composed of 11 highly conserved proteins integrated into the membrane of mature virions. Recent advances in methodological techniques have again revealed several connections between VACV EFC proteins. In this study, we explored the possibility of an analogous ASFV EFC by identifying ten candidate proteins exhibiting structural similarities with VACV EFC proteins. This could reveal key functions of these ASFV proteins, drawing attention to shared features between the two virus families, suggesting the potential existence of an ASFV entry-fusion complex.
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Affiliation(s)
- Jesús Urquiza
- Departamento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (M.Á.C.-G.); (I.G.-D.); (A.d.P.)
| | - Miguel Ángel Cuesta-Geijo
- Departamento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (M.Á.C.-G.); (I.G.-D.); (A.d.P.)
| | - Isabel García-Dorival
- Departamento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (M.Á.C.-G.); (I.G.-D.); (A.d.P.)
| | - Óscar Fernández
- Unidad BICS, Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain; (Ó.F.); (J.F.D.)
| | - Ana del Puerto
- Departamento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (M.Á.C.-G.); (I.G.-D.); (A.d.P.)
| | - José Fernando Díaz
- Unidad BICS, Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain; (Ó.F.); (J.F.D.)
| | - Covadonga Alonso
- Departamento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (M.Á.C.-G.); (I.G.-D.); (A.d.P.)
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4
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Hernandez-Gonzalez M, Calcraft T, Nans A, Rosenthal PB, Way M. Palisade structure in intact vaccinia virions. mBio 2024; 15:e0313423. [PMID: 38171004 PMCID: PMC10865856 DOI: 10.1128/mbio.03134-23] [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: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 01/05/2024] Open
Abstract
Vaccinia virus assembly in the cytoplasm of infected cells involves the formation of a biconcave viral core inside the maturing viral particle. The boundary of the core is defined by a pseudohexagonal palisade layer, composed of trimers projecting from an inner wall. To understand the assembly of this complex core architecture, we obtained a subnanometer structure of the palisade trimer by cryo-electron tomography and subtomogram averaging of purified intact virions. Using AlphaFold2 structure predictions, we determined that the palisade is formed from trimers of the proteolytically processed form of the viral protein A10. In addition, we found that each A10 protomer associates with an α-helix (residues 24-66) of A4. Cellular localization assays outside the context of infection demonstrate that the A4 N-terminus is necessary and sufficient to interact with A10. The interaction between A4 and A10 provides insights into how the palisade layer might become tightly associated with the viral membrane during virion maturation. Reconstruction of the palisade layer reveals that, despite local hexagonal ordering, the A10/A4 trimers are widely spaced, suggesting that additional components organize the lattice. This spacing would, however, allow the adoption of the characteristic biconcave shape of the viral core. Finally, we also found that the palisade incorporates multiple copies of a hexameric portal structure. We suggest that these portals are formed by E6, a viral protein that is essential for virion assembly and required to release viral mRNA from the core early in infection.IMPORTANCEPoxviruses such as variola virus (smallpox) and monkeypox cause diseases in humans. Other poxviruses, including vaccinia and modified vaccinia Ankara, are used as vaccine vectors. Given their importance, a greater structural understanding of poxvirus virions is needed. We now performed cryo-electron tomography of purified intact vaccinia virions to study the structure of the palisade, a protein lattice that defines the viral core boundary. We identified the main viral proteins that form the palisade and their interaction surfaces and provided new insights into the organization of the viral core.
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Affiliation(s)
- Miguel Hernandez-Gonzalez
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Thomas Calcraft
- Structural Biology of Cells and Viruses Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Andrea Nans
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Peter B. Rosenthal
- Structural Biology of Cells and Viruses Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Michael Way
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, London, United Kingdom
- Department of Infectious Disease, Imperial College, London, United Kingdom
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5
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Beaud G, Costa F, Klonjkowski B, Piumi F, Coulpier M, Drillien R, Monsion B, Mohd Jaafar F, Attoui H. Vaccinia Virus Defective Particles Lacking the F17 Protein Do Not Inhibit Protein Synthesis: F17, a Double-Edged Sword for Protein Synthesis? Int J Mol Sci 2024; 25:1382. [PMID: 38338659 PMCID: PMC10855608 DOI: 10.3390/ijms25031382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/16/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024] Open
Abstract
Vaccinia virus (Orthopoxvirus) F17 protein is a major virion structural phosphoprotein having a molecular weight of 11 kDa. Recently, it was shown that F17 synthesised in infected cells interacts with mTOR subunits to evade cell immunity and stimulate late viral protein synthesis. Several years back, we purified an 11 kDa protein that inhibited protein synthesis in reticulocyte lysate from virions, and that possesses all physico-chemical properties of F17 protein. To investigate this discrepancy, we used defective vaccinia virus particles devoid of the F17 protein (designated iF17- particles) to assess their ability to inhibit protein synthesis. To this aim, we purified iF17- particles from cells infected with a vaccinia virus mutant which expresses F17 only in the presence of IPTG. The SDS-PAGE protein profiles of iF17- particles or derived particles, obtained by solubilisation of the viral membrane, were similar to that of infectious iF17 particles. As expected, the profiles of full iF17- particles and those lacking the viral membrane were missing the 11 kDa F17 band. The iF17- particles did attach to cells and injected their viral DNA into the cytoplasm. Co-infection of the non-permissive BSC40 cells with a modified vaccinia Ankara (MVA) virus, expressing an mCherry protein, and iF17- particles, induced a strong mCherry fluorescence. Altogether, these experiments confirmed that the iF17- particles can inject their content into cells. We measured the rate of protein synthesis as a function of the multiplicity of infection (MOI), in the presence of puromycin as a label. We showed that iF17- particles did not inhibit protein synthesis at high MOI, by contrast to the infectious iF17 mutant. Furthermore, the measured efficiency to inhibit protein synthesis by the iF17 mutant virus generated in the presence of IPTG, was threefold to eightfold lower than that of the wild-type WR virus. The iF17 mutant contained about threefold less F17 protein than wild-type WR. Altogether these results strongly suggest that virion-associated F17 protein is essential to mediate a stoichiometric inhibition of protein synthesis, in contrast to the late synthesised F17. It is possible that this discrepancy is due to different phosphorylation states of the free and virion-associated F17 protein.
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Affiliation(s)
- Georges Beaud
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
| | - Fleur Costa
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
| | - Bernard Klonjkowski
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
| | - François Piumi
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
| | - Muriel Coulpier
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
| | - Robert Drillien
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, INSERM U596/CNRS-UMR7104, Université Louis Pasteur, F-67404 Strasbourg, France;
| | - Baptiste Monsion
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
| | - Fauziah Mohd Jaafar
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
| | - Houssam Attoui
- INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, UMR VIROLOGIE, Laboratoire de Santé Animale, F-94700 Maisons-Alfort, France; (F.C.); (B.K.); (F.P.); (M.C.); (B.M.); (F.M.J.)
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6
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Aggarwal T, Kondabagil K. Assembly and Evolution of Poxviruses. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1451:35-54. [PMID: 38801570 DOI: 10.1007/978-3-031-57165-7_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Poxvirus assembly has been an intriguing area of research for several decades. While advancements in experimental techniques continue to yield fresh insights, many questions are still unresolved. Large genome sizes of up to 380 kbp, asymmetrical structure, an exterior lipid bilayer, and a cytoplasmic life cycle are some notable characteristics of these viruses. Inside the particle are two lateral bodies and a protein wall-bound-biconcave core containing the viral nucleocapsid. The assembly progresses through five major stages-endoplasmic reticulum (ER) membrane alteration and rupture, crescent formation, immature virion formation, genome encapsidation, virion maturation and in a subset of viruses, additional envelopment of the virion prior to its dissemination. Several large dsDNA viruses have been shown to follow a comparable sequence of events. In this chapter, we recapitulate our understanding of the poxvirus morphogenesis process while reviewing the most recent advances in the field. We also briefly discuss how virion assembly aids in our knowledge of the evolutionary links between poxviruses and other Nucleocytoplasmic Large DNA Viruses (NCLDVs).
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Affiliation(s)
- Tanvi Aggarwal
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, 400076, India
| | - Kiran Kondabagil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, 400076, India.
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7
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Riccardo V, Pablo GC. Neutralization Determinants on Poxviruses. Viruses 2023; 15:2396. [PMID: 38140637 PMCID: PMC10747254 DOI: 10.3390/v15122396] [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: 11/10/2023] [Revised: 12/04/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
Smallpox was a highly contagious disease caused by the variola virus. The disease affected millions of people over thousands of years and variola virus ranked as one of the deadliest viruses in human history. The complete eradication of smallpox in 1980, a major triumph in medicine, was achieved through a global vaccination campaign using a less virulent poxvirus, vaccinia virus. Despite this success, the herd immunity established by this campaign has significantly waned, and concerns are rising about the potential reintroduction of variola virus as a biological weapon or the emergence of zoonotic poxviruses. These fears were further fueled in 2022 by a global outbreak of monkeypox virus (mpox), which spread to over 100 countries, thereby boosting interest in developing new vaccines using molecular approaches. However, poxviruses are complex and creating modern vaccines against them is challenging. This review focuses on the structural biology of the six major neutralization determinants on poxviruses (D8, H3, A27, L1, B5, and A33), the localization of epitopes targeted by neutralizing antibodies, and their application in the development of subunit vaccines.
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Affiliation(s)
| | - Guardado-Calvo Pablo
- Structural Biology of Infectious Diseases Unit, Institut Pasteur, Université Paris Cité, F-75015 Paris, France;
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Lin S, Yue D, Yang F, Chen Z, He B, Cao Y, Dong H, Li J, Zhao Q, Lu G. Crystal structure of vaccinia virus G3/L5 sub-complex reveals a novel fold with extended inter-molecule interactions conserved among orthopoxviruses. Emerg Microbes Infect 2023; 12:e2160661. [PMID: 36533407 PMCID: PMC9848366 DOI: 10.1080/22221751.2022.2160661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Sheng Lin
- West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
| | - Dan Yue
- West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
| | - Fanli Yang
- West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
| | - Zimin Chen
- West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
| | - Bin He
- West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
| | - Yu Cao
- West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China,Disaster Medicine Center, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
| | - Haohao Dong
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy and Cancer Center, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
| | - Jian Li
- School of Basic Medical Sciences, Chengdu University, Chengdu, People’s Republic of China
| | - Qi Zhao
- College of Food and Biological Engineering, Chengdu University, Chengdu, People’s Republic of China
| | - Guangwen Lu
- West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China, Guangwen Lu West China Hospital Emergency Department (WCHED), State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan610041, People’s Republic of China
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9
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Mirzakhanyan Y, Jankevics A, Scheltema RA, Gershon PD. Combination of deep XLMS with deep learning reveals an ordered rearrangement and assembly of a major protein component of the vaccinia virion. mBio 2023; 14:e0113523. [PMID: 37646531 PMCID: PMC10653903 DOI: 10.1128/mbio.01135-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 07/11/2023] [Indexed: 09/01/2023] Open
Abstract
IMPORTANCE An outstanding problem in the understanding of poxvirus biology is the molecular structure of the mature virion. Via deep learning methods combined with chemical cross-linking mass spectrometry, we have addressed the structure and assembly pathway of P4a, a key poxvirus virion core component.
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Affiliation(s)
- Yeva Mirzakhanyan
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, USA
| | - Andris Jankevics
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, the Netherlands
| | - Richard A. Scheltema
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, the Netherlands
| | - Paul David Gershon
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, USA
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10
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Bogdanow B, Gruska I, Mühlberg L, Protze J, Hohensee S, Vetter B, Bosse JB, Lehmann M, Sadeghi M, Wiebusch L, Liu F. Spatially resolved protein map of intact human cytomegalovirus virions. Nat Microbiol 2023; 8:1732-1747. [PMID: 37550507 PMCID: PMC10465357 DOI: 10.1038/s41564-023-01433-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 06/20/2023] [Indexed: 08/09/2023]
Abstract
Herpesviruses assemble large enveloped particles that are difficult to characterize structurally due to their size, fragility and complex multilayered proteome with partially amorphous nature. Here we used crosslinking mass spectrometry and quantitative proteomics to derive a spatially resolved interactome map of intact human cytomegalovirus virions. This enabled the de novo allocation of 32 viral proteins into four spatially resolved virion layers, each organized by a dominant viral scaffold protein. The viral protein UL32 engages with all layers in an N-to-C-terminal radial orientation, bridging nucleocapsid to viral envelope. We observed the layer-specific incorporation of 82 host proteins, of which 39 are selectively recruited. We uncovered how UL32, by recruitment of PP-1 phosphatase, antagonizes binding to 14-3-3 proteins. This mechanism assures effective viral biogenesis, suggesting a perturbing role of UL32-14-3-3 interaction. Finally, we integrated these data into a coarse-grained model to provide global insights into the native configuration of virus and host protein interactions inside herpesvirions.
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Affiliation(s)
- Boris Bogdanow
- Research group 'Structural Interactomics', Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.
| | - Iris Gruska
- Labor für Pädiatrische Molekularbiologie, Department of Pediatric Oncology and Hematology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Lars Mühlberg
- Research group 'Structural Interactomics', Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Jonas Protze
- Research group 'Structural Bioinformatics', Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Svea Hohensee
- Cellular Imaging core facility, Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Barbara Vetter
- Labor für Pädiatrische Molekularbiologie, Department of Pediatric Oncology and Hematology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jens B Bosse
- Centre for Structural Systems Biology, Hamburg, Germany
- Hannover Medical School, Institute of Virology, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Leibniz-Institute of Virology (LIV), Hamburg, Germany
| | - Martin Lehmann
- Cellular Imaging core facility, Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Mohsen Sadeghi
- Department of Mathematics and Computer Science, Freie Universität Berlin, Berlin, Germany.
| | - Lüder Wiebusch
- Labor für Pädiatrische Molekularbiologie, Department of Pediatric Oncology and Hematology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
| | - Fan Liu
- Research group 'Structural Interactomics', Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.
- Charité Universitätsmedizin Berlin, Berlin, Germany.
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11
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Bécares M, Albert M, Tárrega C, Coloma R, Falqui M, Luhmann EK, Radoshevich L, Guerra S. ISG15 Is Required for the Dissemination of Vaccinia Virus Extracellular Virions. Microbiol Spectr 2023; 11:e0450822. [PMID: 37036376 PMCID: PMC10269806 DOI: 10.1128/spectrum.04508-22] [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: 11/04/2022] [Accepted: 03/15/2023] [Indexed: 04/11/2023] Open
Abstract
Viruses have developed many different strategies to counteract immune responses, and Vaccinia virus (VACV) is one of a kind in this aspect. To ensure an efficient infection, VACV undergoes a complex morphogenetic process resulting in the production of two types of infective virions: intracellular mature virus (MV) and extracellular enveloped virus (EV), whose spread depends on different dissemination mechanisms. MVs disseminate after cell lysis, whereas EVs are released or propelled in actin tails from living cells. Here, we show that ISG15 participates in the control of VACV dissemination. Infection of Isg15-/- mouse embryonic fibroblasts with VACV International Health Department-J (IHD-J) strain resulted in decreased EV production, concomitant with reduced induction of actin tails and the abolition of comet-shaped plaque formation, compared to Isg15+/+ cells. Transmission electron microscopy revealed the accumulation of intracellular virus particles and a decrease in extracellular virus particles in the absence of interferon-stimulated gene 15 (ISG15), a finding consistent with altered virus egress. Immunoblot and quantitative proteomic analysis of sucrose gradient-purified virions from both genotypes reported differences in protein levels and composition of viral proteins present on virions, suggesting an ISG15-mediated control of viral proteome. Lastly, the generation of a recombinant IHD-J expressing V5-tagged ISG15 (IHD-J-ISG15) allowed us to identify several viral proteins as potential ISG15 targets, highlighting the proteins A34 and A36, which are essential for EV formation. Altogether, our results indicate that ISG15 is an important host factor in the regulation of VACV dissemination. IMPORTANCE Viral infections are a constant battle between the virus and the host. While the host's only goal is victory, the main purpose of the virus is to spread and conquer new territories at the expense of the host's resources. Along millions of years of incessant encounters, poxviruses have developed a unique strategy consisting in the production two specialized "troops": intracellular mature virions (MVs) and extracellular virions (EVs). MVs mediate transmission between hosts, and EVs ensure advance on the battlefield mediating the long-range dissemination. The mechanism by which the virus "decides" to shed from the primary site of infection and its significant impact in viral transmission is not yet fully established. Here, we demonstrate that this process is finely regulated by ISG15/ISGylation, an interferon-induced ubiquitin-like protein with broad antiviral activity. Studying the mechanism that viruses use during infection could result in new ways of understanding our perpetual war against disease and how we might win the next great battle.
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Affiliation(s)
- Martina Bécares
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Manuel Albert
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Céline Tárrega
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Rocío Coloma
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Michela Falqui
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Emma K. Luhmann
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Lilliana Radoshevich
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Susana Guerra
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, Madrid, Spain
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12
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Yang N, Wang Y, Dai P, Li T, Zierhut C, Tan A, Zhang T, Xiang JZ, Ordureau A, Funabiki H, Chen Z, Deng L. Vaccinia E5 is a major inhibitor of the DNA sensor cGAS. Nat Commun 2023; 14:2898. [PMID: 37217469 PMCID: PMC10201048 DOI: 10.1038/s41467-023-38514-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 05/05/2023] [Indexed: 05/24/2023] Open
Abstract
The DNA sensor cyclic GMP-AMP synthase (cGAS) is critical in host antiviral immunity. Vaccinia virus (VACV) is a large cytoplasmic DNA virus that belongs to the poxvirus family. How vaccinia virus antagonizes the cGAS-mediated cytosolic DNA-sensing pathway is not well understood. In this study, we screened 80 vaccinia genes to identify potential viral inhibitors of the cGAS/Stimulator of interferon gene (STING) pathway. We discovered that vaccinia E5 is a virulence factor and a major inhibitor of cGAS. E5 is responsible for abolishing cGAMP production during vaccinia virus (Western Reserve strain) infection of dendritic cells. E5 localizes to the cytoplasm and nucleus of infected cells. Cytosolic E5 triggers ubiquitination of cGAS and proteasome-dependent degradation via interacting with cGAS. Deleting the E5R gene from the Modified vaccinia virus Ankara (MVA) genome strongly induces type I IFN production by dendritic cells (DCs) and promotes DC maturation, and thereby improves antigen-specific T cell responses.
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Affiliation(s)
- Ning Yang
- Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
| | - Yi Wang
- Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Peihong Dai
- Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Tuo Li
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Christian Zierhut
- Laboratory of Chromosome and Cell Biology, The Rockefeller University, New York, NY, 10065, USA
- The Institute of Cancer Research, London, SW3 6JB, UK
| | - Adrian Tan
- Genomic Resources Core Facility, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Tuo Zhang
- Genomic Resources Core Facility, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Jenny Zhaoying Xiang
- Genomic Resources Core Facility, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Alban Ordureau
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Hironori Funabiki
- Laboratory of Chromosome and Cell Biology, The Rockefeller University, New York, NY, 10065, USA
| | - Zhijian Chen
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Liang Deng
- Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
- Weill Cornell Medical College, New York, NY, 10065, USA.
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13
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Molteni C, Forni D, Cagliani R, Mozzi A, Clerici M, Sironi M. Evolution of the orthopoxvirus core genome. Virus Res 2023; 323:198975. [PMID: 36280003 PMCID: PMC9586335 DOI: 10.1016/j.virusres.2022.198975] [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: 07/20/2022] [Revised: 10/17/2022] [Accepted: 10/18/2022] [Indexed: 11/07/2022]
Abstract
Orthopoxviruses comprise several relevant pathogens, including the causative agent of smallpox and monkeypox virus. Analysis of orthopoxvirus genome evolution mainly focused on gene gains/losses. We instead analyzed core genes, which are conserved in all orthopoxviruses. We show that, despite their strong constraint, some genes involved in viral morphogenesis and transcription/replication were targets of pervasive positive selection, which was relatively uncommon in immunomodulatory genes. However at least three of the positively selected genes, E3L, A24R, and H3L, might have evolved in response to immune selection. Episodic positive selection was particularly common on the internal branches of the orthopox phylogeny and on the monkeypox virus lineage. The latter showed evidence of episodic positive selection at the D14L gene, which encodes a modulator of complement activation (MOPICE). Notably, two genes (B1R and A33R) targeted by episodic selection on more than one branch are involved in forms of intra-genomic conflict. Finally, we found that, in orthopoxvirus proteomes, intrinsically disordered regions (IDRs) tend to be less constrained and are common targets of positive selection. Extension of our analysis to all poxviruses showed no evidence that the IDR fraction differs with host range. Conversely, we found a strong effect of base composition, which was however not sufficient to explain IDR fraction. We thus suggest that, in poxviruses, the IDR fraction is maintained by modulating GC content to accommodate disorder-promoting codons. Overall, our data provide novel insight in orthopoxvirus evolution and provide a list of genes and sites that are expected to modulate viral phenotypes.
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Affiliation(s)
- Cristian Molteni
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini, Italy.
| | - Diego Forni
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini, Italy
| | - Rachele Cagliani
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini, Italy
| | - Alessandra Mozzi
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini, Italy
| | - Mario Clerici
- University of Milan, Milan, Italy; Don C. Gnocchi Foundation ONLUS, IRCCS, Milan, Italy
| | - Manuela Sironi
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini, Italy
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Rabaan AA, Abas AH, Tallei TE, Al-Zaher MA, Al-Sheef NM, Fatimawali, Al-Nass EZ, Al-Ebrahim EA, Effendi Y, Idroes R, Alhabib MF, Al-Fheid HA, Adam AA, Bin Emran T. Monkeypox outbreak 2022: What we know so far and its potential drug targets and management strategies. J Med Virol 2023; 95:e28306. [PMID: 36372558 DOI: 10.1002/jmv.28306] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/28/2022] [Accepted: 11/10/2022] [Indexed: 11/15/2022]
Abstract
Monkeypox is a rare zoonotic disease caused by infection with the monkeypox virus. The disease can result in flu-like symptoms, fever, and a persistent rash. The disease is currently spreading throughout the world and prevention and treatment efforts are being intensified. Although there is no treatment that has been specifically approved for monkeypox virus infection, infected patients may benefit from using certain antiviral medications that are typically prescribed for the treatment of smallpox. The drugs are tecovirimat, brincidofovir, and cidofovir, all of which are currently in short supply due to the spread of the monkeypox virus. Resistance is also a concern, as widespread replication of the monkeypox virus can lead to mutations that produce monkeypox viruses that are resistant to the currently available treatments. This article discusses monkeypox disease, potential drug targets, and management strategies to overcome monkeypox disease. With the discovery of new drugs, it is hoped that the problem of insufficient drugs will be resolved, and it is not anticipated that drug resistance will become a major issue in the near future.
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Affiliation(s)
- Ali A Rabaan
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia.,Molecular Diagnostic Laboratory, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia.,Department of Public Health and Nutrition, The University of Haripur, Haripur, Pakistan
| | - Abdul Hawil Abas
- Faculty of Bioscience and Engineering, Ghent University, Ghent, Belgium
| | - Trina Ekawati Tallei
- Department of Biology, Faculty of Mathematics and Natural Sciences, Sam Ratulangi University, Manado, North Sulawesi, Indonesia
| | - Mona A Al-Zaher
- Department of Commitment management, Directorate of Health Affairs in the Eastern Province, Dammam, Saudi Arabia
| | - Noor M Al-Sheef
- Department of Commitment management, Directorate of Health Affairs in the Eastern Province, Dammam, Saudi Arabia
| | - Fatimawali
- Pharmacy Study Program, Faculty of Mathematics and Natural Sciences, Sam Ratulangi University, Manado, North Sulawesi, Indonesia
| | - Esraa Z Al-Nass
- Department of Commitment management, Directorate of Health Affairs in the Eastern Province, Dammam, Saudi Arabia
| | - Eba A Al-Ebrahim
- Department of Commitment management, Directorate of Health Affairs in the Eastern Province, Dammam, Saudi Arabia
| | - Yunus Effendi
- Department of Biology, Faculty of Science and Technology, Al-Azhar Indonesia University, Jakarta, Indonesia
| | - Rinaldi Idroes
- Department of Pharmacy, Faculty of Mathematics and Natural Sciences, Universitas Syiah Kuala, Banda Aceh, Aceh, Indonesia
| | - Mather F Alhabib
- Molecular Diagnostic Laboratory, Dammam Regional Laboratory and Blood Bank, Dammam, Saudi Arabia
| | - Hussain A Al-Fheid
- Molecular Diagnostic Laboratory, Dammam Regional Laboratory and Blood Bank, Dammam, Saudi Arabia
| | - Ahmad Akroman Adam
- Dentistry Study Program, Faculty of Medicine, Sam Ratulangi University, Manado, North Sulawesi, Indonesia
| | - Talha Bin Emran
- Department of Pharmacy, BGC Trust University Bangladesh, Chittagong, Bangladesh.,Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
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15
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Bidgood SR, Samolej J, Novy K, Collopy A, Albrecht D, Krause M, Burden JJ, Wollscheid B, Mercer J. Poxviruses package viral redox proteins in lateral bodies and modulate the host oxidative response. PLoS Pathog 2022; 18:e1010614. [PMID: 35834477 PMCID: PMC9282662 DOI: 10.1371/journal.ppat.1010614] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 05/24/2022] [Indexed: 01/23/2023] Open
Abstract
All poxviruses contain a set of proteinaceous structures termed lateral bodies (LB) that deliver viral effector proteins into the host cytosol during virus entry. To date, the spatial proteotype of LBs remains unknown. Using the prototypic poxvirus, vaccinia virus (VACV), we employed a quantitative comparative mass spectrometry strategy to determine the poxvirus LB proteome. We identified a large population of candidate cellular proteins, the majority being mitochondrial, and 15 candidate viral LB proteins. Strikingly, one-third of these are VACV redox proteins whose LB residency could be confirmed using super-resolution microscopy. We show that VACV infection exerts an anti-oxidative effect on host cells and that artificial induction of oxidative stress impacts early and late gene expression as well as virion production. Using targeted repression and/or deletion viruses we found that deletion of individual LB-redox proteins was insufficient for host redox modulation suggesting there may be functional redundancy. In addition to defining the spatial proteotype of VACV LBs, these findings implicate poxvirus redox proteins as potential modulators of host oxidative anti-viral responses and provide a solid starting point for future investigations into the role of LB resident proteins in host immunomodulation.
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Affiliation(s)
- Susanna R. Bidgood
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Jerzy Samolej
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Karel Novy
- Swiss Federal Institute of Technology (ETH Zürich), Department of Health Sciences and Technology (D-HEST), Institute of Translational Medicine (ITM), Zürich, Switzerland
| | - Abigail Collopy
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - David Albrecht
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Melanie Krause
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Jemima J. Burden
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Bernd Wollscheid
- Swiss Federal Institute of Technology (ETH Zürich), Department of Health Sciences and Technology (D-HEST), Institute of Translational Medicine (ITM), Zürich, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Jason Mercer
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, United Kingdom
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16
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Diesterbeck US, Ahsendorf HP, Frenzel A, Sharifi AR, Schirrmann T, Czerny CP. Characterization of an In Vivo Neutralizing Anti-Vaccinia Virus D8 Single-Chain Fragment Variable (scFv) from a Human Anti-Vaccinia Virus-Specific Recombinant Library. Vaccines (Basel) 2021; 9:vaccines9111308. [PMID: 34835240 PMCID: PMC8619513 DOI: 10.3390/vaccines9111308] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/29/2021] [Accepted: 11/05/2021] [Indexed: 11/16/2022] Open
Abstract
A panel of potent neutralizing antibodies are protective against orthopoxvirus (OPXV) infections. For the development of OPXV-specific recombinant human single-chain antibodies (scFvs), the IgG repertoire of four vaccinated donors was amplified from peripheral B-lymphocytes. The resulting library consisted of ≥4 × 108 independent colonies. The immuno-screening against vaccinia virus (VACV) Elstree revealed a predominant selection of scFv clones specifically binding to the D8 protein. The scFv-1.2.2.H9 was engineered into larger human scFv-Fc-1.2.2.H9 and IgG1-1.2.2.H9 formats to improve the binding affinity and to add effector functions within the human immune response. Similar binding kinetics were calculated for scFv-1.2.2.H9 and scFv-Fc-1.2.2.H9 (1.61 nM and 7.685 nM, respectively), whereas, for IgG1-1.2.2.H9, the Michaelis-Menten kinetics revealed an increased affinity of 43.8 pM. None of the purified recombinant 1.2.2.H9 formats were able to neutralize VACV Elstree in vitro. After addition of 1% human complement, the neutralization of ≥50% of VACV Elstree was achieved with 0.0776 µM scFv-Fc-1.2.2.H9 and 0.01324 µM IgG1-1.2.2.H9, respectively. In an in vivo passive immunization NMRI mouse model, 100 µg purified scFv-1.2.2.H9 and the IgG1-1.2.2.H9 partially protected against the challenge with 4 LD50 VACV Munich 1, as 3/6 mice survived. In contrast, in the scFv-Fc-1.2.2.H9 group, only one mouse survived the challenge.
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Affiliation(s)
- Ulrike S. Diesterbeck
- Division of Microbiology and Animal Hygiene, Department of Animal Sciences, University of Göttingen, Burckhardtweg 2, 37077 Göttingen, Germany;
- Correspondence:
| | - Henrike P. Ahsendorf
- Division of Microbiology and Animal Hygiene, Department of Animal Sciences, University of Göttingen, Burckhardtweg 2, 37077 Göttingen, Germany;
| | - André Frenzel
- Yumab GmbH, Science Campus Braunschweig Sued, Inhoffenstr. 7, 38124 Braunschweig, Germany; (A.F.); (T.S.)
| | - Ahmad Reza Sharifi
- Center for Integrated Breeding Research, Department of Animal Sciences, University of Göttingen, Albrecht-Thaer-Weg 3, 37075 Göttingen, Germany;
| | - Thomas Schirrmann
- Yumab GmbH, Science Campus Braunschweig Sued, Inhoffenstr. 7, 38124 Braunschweig, Germany; (A.F.); (T.S.)
| | - Claus-Peter Czerny
- Division of Microbiology and Animal Hygiene, Department of Animal Sciences, University of Göttingen, Burckhardtweg 2, 37077 Göttingen, Germany;
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17
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Insights into the Organization of the Poxvirus Multicomponent Entry-Fusion Complex from Proximity Analyses in Living Infected Cells. J Virol 2021; 95:e0085221. [PMID: 34076488 DOI: 10.1128/jvi.00852-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Poxviruses are exceptional in having a complex entry-fusion complex (EFC) that is comprised of 11 conserved proteins embedded in the membrane of mature virions. However, the detailed architecture is unknown and only a few bimolecular protein interactions have been demonstrated by coimmunoprecipitation from detergent-treated lysates and by cross-linking. Here, we adapted the tripartite split green fluorescent protein (GFP) complementation system in order to analyze EFC protein contacts within living cells. This system employs a detector fragment called GFP1-9 comprised of nine GFP β-strands. To achieve fluorescence, two additional 20-amino-acid fragments called GFP10 and GFP11 attached to interacting proteins are needed, providing the basis for identification of the latter. We constructed a novel recombinant vaccinia virus (VACV-GFP1-9) expressing GFP1-9 under a viral early/late promoter and plasmids with VACV late promoters regulating each of the EFC proteins with GFP10 or GFP11 attached to their ectodomains. GFP fluorescence was detected by confocal microscopy at sites of virion assembly in cells infected with VACV-GFP1-9 and cotransfected with plasmids expressing one EFC-GFP10 and one EFC-GFP11 interacting protein. Flow cytometry provided a quantitative way to determine the interaction of each EFC-GFP10 protein with every other EFC-GFP11 protein in the context of a normal infection in which all viral proteins are synthesized and assembled. Previous EFC protein interactions were confirmed, and new ones were discovered and corroborated by additional methods. Most remarkable was the finding that the small, hydrophobic O3 protein interacted with each of the other EFC proteins. IMPORTANCE Poxviruses are enveloped viruses with a DNA-containing core that enters cells following fusion of viral and host membranes. This essential step is a target for vaccines and therapeutics. The entry-fusion complex (EFC) of poxviruses is unusually complex and comprised of 11 conserved viral proteins. Determination of the structure of the EFC is a prerequisite for understanding the fusion mechanism. Here, we used a tripartite split green fluorescent protein assay to determine the proximity of individual EFC proteins in living cells. A network connecting components of the EFC was derived.
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18
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Loss of the vaccinia virus 35-amino acid hydrophobic O3 protein is partially compensated by mutations in the transmembrane domains of other entry proteins. J Virol 2021; 95:JVI.02228-20. [PMID: 33504600 PMCID: PMC8103694 DOI: 10.1128/jvi.02228-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Eleven highly conserved proteins comprise the poxvirus entry-fusion complex (EFC). We focused on vaccinia virus (VACV) O3, a 35-amino acid, largely hydrophobic component of unknown specific function. Experimental evolution was carried out by blindly passaging a virus that was severely impaired in entry due to deletion of the gene encoding O3. Large plaque variants that arose spontaneously were discerned by round four and their numbers increased thereafter. Genome sequencing of individual cloned viruses revealed mutations in predicted transmembrane domains of three open reading frames encoding proteins with roles in entry. There were frame-shift mutations in consecutive Ts in open reading frames F9L and D8L and a nonsynonymous base substitution in L5R. F9 and L5 are EFC proteins and D8 is involved in VACV cell attachment. The F9L mutation occurred by round four in each of three independant passages, whereas the L5R and D8L mutations were detected only after nearly all of the genomes already had the F9L mutation. Viruses with deletions of O3L and single or double F9L, L5R and D8L mutations were constructed by homologous recombination. In a single round of infection, viruses with adaptive mutations including F9L alone or in combination exhibited statistically significant higher virus titers than the parental O3L deletion mutant or the L5R or D8L mutants, consistent with the order of selection during the passages. Further analyses indicated that the adaptive F9L mutants also had higher infectivities, entered cells more rapidly and increased EFC assembly, which partially compensated for the loss of O3.IMPORTANCE Entry into cells is an essential first step in virus replication and an important target of vaccine- elicited immunity. For enveloped viruses, this step involves the fusion of viral and host membranes to form a pore allowing entry of the genome and associated proteins. Poxviruses are unique in that this function is mediated by an entry-fusion complex (EFC) of eleven transmembrane proteins rather than by one or a few. The large number of proteins has hindered investigation of their individual roles. We focused on O3, a predominantly hydrophobic 35 amino acid component of the vaccinia virus EFC, and found that spontaneous mutations in the transmembrane domains of certain other entry proteins can partially compensate for the absence of O3. The mutants exhibited increased infectivity, entry and assembly or stability of the EFC.
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19
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Abstract
Mass spectrometry imaging (MSI) is a label-free molecular imaging technique allowing an untargeted detection of a broad range of biomolecules and xenobiotics. MSI enables imaging of the spatial distribution of proteins, peptides, lipids and metabolites from a wide range of samples. To date, this technique is commonly applied to tissue sections in cancer diagnostics and biomarker development, but also molecular histology in general. Advances in the methodology and bioinformatics improved the resolution of MS images below the single cell level and increased the flexibility of the workflow. However, MSI-based research in virology is just starting to gain momentum and its full potential has not been exploited yet. In this review, we discuss the main applications of MSI in virology. We review important aspects of matrix-assisted laser desorption/ionization (MALDI) MSI, the most widely used MSI technique in virology. In addition, we summarize relevant literature on MSI studies that aim to unravel virus-host interactions and virus pathogenesis, to elucidate antiviral drug kinetics and to improve current viral disease diagnostics. Collectively, these studies strongly improve our general understanding of virus-induced changes in the proteome, metabolome and metabolite distribution in host tissues of humans, animals and plants upon infection. Furthermore, latest MSI research provided important insights into the drug distribution and distribution kinetics, especially in antiretroviral research. Finally, MSI-based investigations of oncogenic viruses greatly increased our knowledge on tumor mass signatures and facilitated the identification of cancer biomarkers.
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Affiliation(s)
- Luca D Bertzbach
- Institute of Virology, Freie Universität Berlin, Berlin, Germany
| | | | - Axel Karger
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany.
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20
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Gray RDM, Albrecht D, Beerli C, Huttunen M, Cohen GH, White IJ, Burden JJ, Henriques R, Mercer J. Nanoscale polarization of the entry fusion complex of vaccinia virus drives efficient fusion. Nat Microbiol 2019; 4:1636-1644. [PMID: 31285583 DOI: 10.1038/s41564-019-0488-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 05/14/2019] [Indexed: 01/29/2023]
Abstract
To achieve efficient binding and subsequent fusion, most enveloped viruses encode between one and five proteins1. For many viruses, the clustering of fusion proteins-and their distribution on virus particles-is crucial for fusion activity2,3. Poxviruses, the most complex mammalian viruses, dedicate 15 proteins to binding and membrane fusion4. However, the spatial organization of these proteins and how this influences fusion activity is unknown. Here, we show that the membrane of vaccinia virus is organized into distinct functional domains that are critical for the efficiency of membrane fusion. Using super-resolution microscopy and single-particle analysis, we found that the fusion machinery of vaccinia virus resides exclusively in clusters at virion tips. Repression of individual components of the fusion complex disrupts fusion-machinery polarization, consistent with the reported loss of fusion activity5. Furthermore, we show that displacement of functional fusion complexes from virion tips disrupts the formation of fusion pores and infection kinetics. Our results demonstrate how the protein architecture of poxviruses directly contributes to the efficiency of membrane fusion, and suggest that nanoscale organization may be an intrinsic property of these viruses to assure successful infection.
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Affiliation(s)
- Robert D M Gray
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
- CoMPLEX, University College London, London, UK
| | - David Albrecht
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Corina Beerli
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Moona Huttunen
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Gary H Cohen
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ian J White
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Jemima J Burden
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Ricardo Henriques
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK.
- Department of Cell and Developmental Biology, University College London, London, UK.
| | - Jason Mercer
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK.
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Chang HW, Yang CH, Luo YC, Su BG, Cheng HY, Tung SY, Carillo KJD, Liao YT, Tzou DLM, Wang HC, Chang W. Vaccinia viral A26 protein is a fusion suppressor of mature virus and triggers membrane fusion through conformational change at low pH. PLoS Pathog 2019; 15:e1007826. [PMID: 31220181 PMCID: PMC6605681 DOI: 10.1371/journal.ppat.1007826] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 07/02/2019] [Accepted: 05/07/2019] [Indexed: 11/24/2022] Open
Abstract
Vaccinia mature virus requires A26 envelope protein to mediate acid-dependent endocytosis into HeLa cells in which we hypothesized that A26 protein functions as an acid-sensitive membrane fusion suppressor. Here, we provide evidence showing that N-terminal domain (aa1-75) of A26 protein is an acid-sensitive region that regulates membrane fusion. Crystal structure of A26 protein revealed that His48 and His53 are in close contact with Lys47, Arg57, His314 and Arg312, suggesting that at low pH these His-cation pairs could initiate conformational changes through protonation of His48 and His53 and subsequent electrostatic repulsion. All the A26 mutant mature viruses that interrupted His-cation pair interactions of His48 and His 53 indeed have lost virion infectivity. Isolation of revertant viruses revealed that second site mutations caused frame shifts and premature termination of A26 protein such that reverent viruses regained cell entry through plasma membrane fusion. Together, we conclude that viral A26 protein functions as an acid-sensitive fusion suppressor during vaccinia mature virus endocytosis. Vaccinia virus is a complex large DNA virus with a large number of viral membrane proteins to facilitate cell entry. Although it is well established that vaccinia mature virus uses endocytosis to enter cells, it remains unclear how it triggers membrane fusion in the acidic environment of endosomes. Recently, we hypothesized that A26 protein in vaccinia mature virus functions as an acid-sensitive membrane fusion suppressor, which suggests a novel viral regulation not present in other enveloped viruses. We postulated that conformational changes of A26 protein at low pH result in de-repression of viral fusion complex activity to trigger viral and endosomal membrane fusion. Here, we provide structural, biochemical and biological evidence demonstrating that vaccinia A26 protein does indeed function as an acid-sensitive fusion suppressor protein to regulate vaccinia mature virus membrane fusion during endocytosis. Our data reveal an important and unique “checkpoint” for vaccinia mature virus endocytosis that has not been described for other viruses. Furthermore, by isolating adaptive vaccinia mutants that escaped endocytic blockage, we discovered that mutations within the A26L gene serve as an effective strategy for switching the viral infection route from endocytosis to plasma membrane fusion, expanding viral host range.
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Affiliation(s)
- Hung-Wei Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Cheng-Han Yang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yu-Chun Luo
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Bo-Gang Su
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Huei-Yin Cheng
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Shu-Yun Tung
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Kathleen Joyce D. Carillo
- Sustainable Chemical Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan
| | - Yi-Ting Liao
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei, Taiwan
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taiwan
| | - Der-Lii M. Tzou
- Sustainable Chemical Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
- Department of Applied Chemistry, National Chia-Yi University, Chia-Yi, Taiwan
| | - Hao-Ching Wang
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei, Taiwan
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taiwan
- * E-mail: (HCW); (WC)
| | - Wen Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- * E-mail: (HCW); (WC)
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