1
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Liu D, Cruz-Cosme R, Wu Y, Leibowitz J, Tang Q. 2-Bromopalmitate depletes lipid droplets to inhibit viral replication. J Virol 2024; 98:e0017124. [PMID: 38488361 PMCID: PMC11019840 DOI: 10.1128/jvi.00171-24] [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: 01/24/2024] [Accepted: 02/26/2024] [Indexed: 04/17/2024] Open
Abstract
The global impact of emerging viral infections emphasizes the urgent need for effective broad-spectrum antivirals. The cellular organelle, lipid droplet (LD), is utilized by many types of viruses for replication, but its reduction does not affect cell survival. Therefore, LD is a potential target for developing broad-spectrum antivirals. In this study, we found that 2-bromopalmitate (2 BP), a previously defined palmitoylation inhibitor, depletes LD across all studied cell lines and exerts remarkable antiviral effects on different coronaviruses. We comprehensively utilized 2 BP, alongside other palmitoylation inhibitors such as cerulenin and 2-fluoro palmitic acid (2-FPA), as well as the enhancer palmostatin B and evaluated their impact on LD and the replication of human coronaviruses (hCoV-229E, hCoV-Oc43) and murine hepatitis virus (MHV-A59) at non-cytotoxic concentrations. While cerulenin and 2-FPA exhibited moderate inhibition of viral replication, 2 BP exhibited a much stronger suppressive effect on MHV-A59 replication, although they share similar inhibitory effects on palmitoylation. As expected, palmostatin B significantly enhanced viral replication, it failed to rescue the inhibitory effects of 2 BP, whereas it effectively counteracted the effects of cerulenin and 2-FPA. This suggests that the mechanism that 2 BP used to inhibit viral replication is beyond palmitoylation inhibition. Further investigations unveil that 2 BP uniquely depletes LDs, a phenomenon not exhibited by 2-FPA and cerulenin. Importantly, the depletion of LDs was closely associated with the inhibition of viral replication because the addition of oleic acid to 2 BP significantly rescued LD depletion and its inhibitory effects on MHV-A59. Our findings indicate that the inhibitory effects of 2 BP on viral replication primarily stem from LD disruption rather than palmitoylation inhibition. Intriguingly, fatty acid (FA) assays demonstrated that 2 BP reduces the FA level in mitochondria while concurrently increasing FA levels in the cytoplasm. These results highlight the crucial role of LDs in viral replication and uncover a novel biological activity of 2 BP. These insights contribute to the development of broad-spectrum antiviral strategies. IMPORTANCE In our study, we conducted a comparative investigation into the antiviral effects of palmitoylation inhibitors including 2-bromopalmitate (2-BP), 2-fluoro palmitic acid (2-FPA), and cerulenin. Surprisingly, we discovered that 2-BP has superior inhibitory effects on viral replication compared to 2-FPA and cerulenin. However, their inhibitory effects on palmitoylation were the same. Intrigued by this finding, we delved deeper into the underlying mechanism of 2-BP's potent antiviral activity, and we unveiled a novel biological activity of 2-BP: depletion of lipid droplets (LDs). Importantly, we also highlighted the crucial role of LDs in viral replication. Our insights shed new light on the antiviral mechanism of LD depletion paving the way for the development of broad-spectrum antiviral strategies by targeting LDs.
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Affiliation(s)
- Dongxiao Liu
- Department of Microbiology, Howard University College of Medicine, Washington, DC, USA
| | - Ruth Cruz-Cosme
- Department of Microbiology, Howard University College of Medicine, Washington, DC, USA
| | - Yong Wu
- Division of Cancer Research and Training, Department of Internal Medicine, Charles Drew University of Medicine and Science, David Geffen UCLA School of Medicine and UCLA Jonsson Comprehensive Cancer Center, Los Angeles, California, USA
| | - Julian Leibowitz
- Microbial Pathogenesis and Immunology, Texas A&M School of Medicine, Bryan, Texas, USA
| | - Qiyi Tang
- Department of Microbiology, Howard University College of Medicine, Washington, DC, USA
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2
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Forrester MT, Egol JR, Tata A, Tata PR, Foster MW. Analysis of Protein Cysteine Acylation Using a Modified Suspension Trap (Acyl-Trap). BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.23.586403. [PMID: 38585928 PMCID: PMC10996552 DOI: 10.1101/2024.03.23.586403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Protein cysteine thiols undergo reversible S-acylation via a thioester linkage in vivo. S-palmitoylation, modification by C16:0 fatty acid, is a common S-acylation that mediates protein-membrane and protein-protein interactions critical to an array of biological processes, from homeostatic lung surfactant function to cellular transformation. The most widely used S-acylation assays, including acyl-biotin exchange (ABE) and acyl resin-assisted capture (Acyl-RAC), utilize blocking of free Cys thiols, hydroxylamine-dependent cleavage of the thioester and subsequent labeling of nascent thiol. ABE and Acyl-RAC have enabled both the proteome-wide identification of S-palmitoylation sites and basic biochemical studies. Yet, these assays generally utilize hundreds of micrograms to milligrams of input material and require numerous reagent removal and washing steps, making them laborious and ill-suited for high throughput and low input applications. To overcome this, we devised "Acyl-Trap", a suspension trap-based assay that utilizes a thiol-reactive quartz to enable buffer exchange and hydroxylamine-mediated S-acyl enrichment from 20-50 micrograms of input protein. The method is compatible with protein-level detection of Sacylated proteins as well as S-acyl site-based identification and quantification using on-quartz isobaric (tandem mass tag) labeling and LC-MS/MS. Also described are conditions for long-term hydroxylamine storage, which further expedites the assay and minimizes waste. More generally, Acyl-Trap serves as a proof-of-concept for PTM-tailored suspension traps suitable for both traditional intact protein detection and chemoproteomic workflows.
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Affiliation(s)
- Michael T Forrester
- Division of Pulmonary, Allergy and Critical Care Medicine, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Jacob R Egol
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Aleksandra Tata
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Purushothama Rao Tata
- Division of Pulmonary, Allergy and Critical Care Medicine, Duke University School of Medicine, Durham, NC, 27710, USA
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA
- Duke Regeneration Center, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Matthew W Foster
- Division of Pulmonary, Allergy and Critical Care Medicine, Duke University School of Medicine, Durham, NC, 27710, USA
- Proteomics and Metabolomics Core Facility, Duke University School of Medicine, Durham, NC, 27710, USA
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3
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Xie M. Virus-Induced Cell Fusion and Syncytia Formation. Results Probl Cell Differ 2024; 71:283-318. [PMID: 37996683 DOI: 10.1007/978-3-031-37936-9_14] [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] [Indexed: 11/25/2023]
Abstract
Most enveloped viruses encode viral fusion proteins to penetrate host cell by membrane fusion. Interestingly, many enveloped viruses can also use viral fusion proteins to induce cell-cell fusion, both in vitro and in vivo, leading to the formation of syncytia or multinucleated giant cells (MGCs). In addition, some non-enveloped viruses encode specialized viral proteins that induce cell-cell fusion to facilitate viral spread. Overall, viruses that can induce cell-cell fusion are nearly ubiquitous in mammals. Virus cell-to-cell spread by inducing cell-cell fusion may overcome entry and post-entry blocks in target cells and allow evasion of neutralizing antibodies. However, molecular mechanisms of virus-induced cell-cell fusion remain largely unknown. Here, I summarize the current understanding of virus-induced cell fusion and syncytia formation.
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Affiliation(s)
- Maorong Xie
- Division of Infection and Immunity, UCL, London, UK.
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4
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Cesar-Silva D, Pereira-Dutra FS, Giannini ALM, Maya-Monteiro CM, de Almeida CJG. Lipid compartments and lipid metabolism as therapeutic targets against coronavirus. Front Immunol 2023; 14:1268854. [PMID: 38106410 PMCID: PMC10722172 DOI: 10.3389/fimmu.2023.1268854] [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: 07/28/2023] [Accepted: 10/24/2023] [Indexed: 12/19/2023] Open
Abstract
Lipids perform a series of cellular functions, establishing cell and organelles' boundaries, organizing signaling platforms, and creating compartments where specific reactions occur. Moreover, lipids store energy and act as secondary messengers whose distribution is tightly regulated. Disruption of lipid metabolism is associated with many diseases, including those caused by viruses. In this scenario, lipids can favor virus replication and are not solely used as pathogens' energy source. In contrast, cells can counteract viruses using lipids as weapons. In this review, we discuss the available data on how coronaviruses profit from cellular lipid compartments and why targeting lipid metabolism may be a powerful strategy to fight these cellular parasites. We also provide a formidable collection of data on the pharmacological approaches targeting lipid metabolism to impair and treat coronavirus infection.
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Affiliation(s)
- Daniella Cesar-Silva
- Laboratory of Immunopharmacology, Department of Genetics, Oswaldo Cruz Institute, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Filipe S. Pereira-Dutra
- Laboratory of Immunopharmacology, Department of Genetics, Oswaldo Cruz Institute, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Ana Lucia Moraes Giannini
- Laboratory of Functional Genomics and Signal Transduction, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Clarissa M. Maya-Monteiro
- Laboratory of Immunopharmacology, Department of Genetics, Oswaldo Cruz Institute, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
- Laboratory of Endocrinology and Department of Endocrinology and Metabolism, Amsterdam University Medical Centers (UMC), University of Amsterdam, Amsterdam, Netherlands
| | - Cecília Jacques G. de Almeida
- Laboratory of Immunopharmacology, Department of Genetics, Oswaldo Cruz Institute, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
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5
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Aliper ET, Efremov RG. Inconspicuous Yet Indispensable: The Coronavirus Spike Transmembrane Domain. Int J Mol Sci 2023; 24:16421. [PMID: 38003610 PMCID: PMC10671605 DOI: 10.3390/ijms242216421] [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] [Revised: 11/07/2023] [Accepted: 11/12/2023] [Indexed: 11/26/2023] Open
Abstract
Membrane-spanning portions of proteins' polypeptide chains are commonly known as their transmembrane domains (TMDs). The structural organisation and dynamic behaviour of TMDs from proteins of various families, be that receptors, ion channels, enzymes etc., have been under scrutiny on the part of the scientific community for the last few decades. The reason for such attention is that, apart from their obvious role as an "anchor" in ensuring the correct orientation of the protein's extra-membrane domains (in most cases functionally important), TMDs often actively and directly contribute to the operation of "the protein machine". They are capable of transmitting signals across the membrane, interacting with adjacent TMDs and membrane-proximal domains, as well as with various ligands, etc. Structural data on TMD arrangement are still fragmentary at best due to their complex molecular organisation as, most commonly, dynamic oligomers, as well as due to the challenges related to experimental studies thereof. Inter alia, this is especially true for viral fusion proteins, which have been the focus of numerous studies for quite some time, but have provoked unprecedented interest in view of the SARS-CoV-2 pandemic. However, despite numerous structure-centred studies of the spike (S) protein effectuating target cell entry in coronaviruses, structural data on the TMD as part of the entire spike protein are still incomplete, whereas this segment is known to be crucial to the spike's fusogenic activity. Therefore, in attempting to bring together currently available data on the structure and dynamics of spike proteins' TMDs, the present review aims to tackle a highly pertinent task and contribute to a better understanding of the molecular mechanisms underlying virus-mediated fusion, also offering a rationale for the design of novel efficacious methods for the treatment of infectious diseases caused by SARS-CoV-2 and related viruses.
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Affiliation(s)
- Elena T. Aliper
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Roman G. Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
- Department of Applied Mathematics, National Research University Higher School of Economics, Moscow 101000, Russia
- L.D. Landau School of Physics, Moscow Institute of Physics and Technology (State University), Dolgoprudny 141701, Russia
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6
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Pezzotti G, Ohgitani E, Fujita Y, Imamura H, Pappone F, Grillo A, Nakashio M, Shin-Ya M, Adachi T, Yamamoto T, Kanamura N, Marin E, Zhu W, Inaba T, Tanino Y, Nukui Y, Higasa K, Yasukochi Y, Okuma K, Mazda O. Raman Fingerprints of SARS-CoV-2 Omicron Subvariants: Molecular Roots of Virological Characteristics and Evolutionary Directions. ACS Infect Dis 2023; 9:2226-2251. [PMID: 37850869 PMCID: PMC10644350 DOI: 10.1021/acsinfecdis.3c00312] [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: 07/03/2023] [Indexed: 10/19/2023]
Abstract
The latest RNA genomic mutation of SARS-CoV-2 virus, termed the Omicron variant, has generated a stream of highly contagious and antibody-resistant strains, which in turn led to classifying Omicron as a variant of concern. We systematically collected Raman spectra from six Omicron subvariants available in Japan (i.e., BA.1.18, BA.2, BA.4, BA.5, XE, and BA.2.75) and applied machine-learning algorithms to decrypt their structural characteristics at the molecular scale. Unique Raman fingerprints of sulfur-containing amino acid rotamers, RNA purines and pyrimidines, tyrosine phenol ring configurations, and secondary protein structures clearly differentiated the six Omicron subvariants. These spectral characteristics, which were linked to infectiousness, transmissibility, and propensity for immune evasion, revealed evolutionary motifs to be compared with the outputs of genomic studies. The availability of a Raman "metabolomic snapshot", which was then translated into a barcode to enable a prompt subvariant identification, opened the way to rationalize in real-time SARS-CoV-2 activity and variability. As a proof of concept, we applied the Raman barcode procedure to a nasal swab sample retrieved from a SARS-CoV-2 patient and identified its Omicron subvariant by coupling a commercially available magnetic bead technology with our newly developed Raman analyses.
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Affiliation(s)
- Giuseppe Pezzotti
- Ceramic
Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
- Department
of Molecular Genetics, Institute of Biomedical Science, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, Osaka 573-1010, Japan
- Department
of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
- Department
of Orthopedic Surgery, Tokyo Medical University, 6-7-1 Nishi-Shinjuku, Shinjuku-ku, 160-0023 Tokyo, Japan
- Department
of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
- Department
of Molecular Science and Nanosystems, Ca’
Foscari University of Venice, Via Torino 155, 30172 Venice, Italy
- Department
of Applied Science and Technology, Politecnico
di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Eriko Ohgitani
- Department
of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Yuki Fujita
- Ceramic
Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
| | - Hayata Imamura
- Ceramic
Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
- Department
of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Francesco Pappone
- Department
of Mathematical Science, Politecnico di
Torino, Corso Duca degli
Abruzzi 24, 10129 Torino, Italy
| | - Alfio Grillo
- Department
of Mathematical Science, Politecnico di
Torino, Corso Duca degli
Abruzzi 24, 10129 Torino, Italy
| | - Maiko Nakashio
- Department
of Infection Control & Laboratory Medicine, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Masaharu Shin-Ya
- Department
of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Tetsuya Adachi
- Department
of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
- Department
of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
- Department
of Microbiology, Kansai Medical University,
School of Medicine, 2-5-1
Shinmachi, Hirakata 573-1010, Osaka Prefecture, Japan
| | - Toshiro Yamamoto
- Department
of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Narisato Kanamura
- Department
of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Elia Marin
- Ceramic
Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
- Department
of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Wenliang Zhu
- Ceramic
Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
| | - Tohru Inaba
- Department
of Infection Control & Laboratory Medicine, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Yoko Tanino
- Department of Clinical Laboratory, University
Hospital, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Yoko Nukui
- Department of Clinical Laboratory, University
Hospital, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Koichiro Higasa
- Genome Analysis, Institute of Biomedical
Science, Kansai Medical University, 2-3-1 Shin-machi, Hirakata, Osaka 573-1191, Japan
| | - Yoshiki Yasukochi
- Genome Analysis, Institute of Biomedical
Science, Kansai Medical University, 2-3-1 Shin-machi, Hirakata, Osaka 573-1191, Japan
| | - Kazu Okuma
- Department
of Microbiology, Kansai Medical University,
School of Medicine, 2-5-1
Shinmachi, Hirakata 573-1010, Osaka Prefecture, Japan
| | - Osam Mazda
- Department
of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
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7
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Dasgupta A, Gangai S, Narayan R, Kapoor S. Mapping the Lipid Signatures in COVID-19 Infection: Diagnostic and Therapeutic Solutions. J Med Chem 2023; 66:14411-14433. [PMID: 37899546 DOI: 10.1021/acs.jmedchem.3c01238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
The COVID-19 pandemic ignited research centered around the identification of robust biomarkers and therapeutic targets. SARS-CoV-2, the virus responsible, hijacks the metabolic machinery of the host cells. It relies on lipids and lipoproteins of host cells for entry, trafficking, immune evasion, viral replication, and exocytosis. The infection causes host cell lipid metabolic remodelling. Targeting lipid-based processes is thus a promising strategy for countering COVID-19. Here, we review the role of lipids in the different steps of the SARS-CoV-2 pathogenesis and identify lipid-centric targetable avenues. We discuss lipidome changes in infected patients and their relevance as potential clinical diagnostic or prognostic biomarkers. We summarize the emerging direct and indirect therapeutic approaches for targeting COVID-19 using lipid-inspired approaches. Given that viral protein-targeted therapies may become less effective due to mutations in emerging SARS-CoV-2 variants, lipid-inspired interventions may provide additional and perhaps better means of combating this and future pandemics.
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Affiliation(s)
- Aishi Dasgupta
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
- IIT-Bombay Monash Academy, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Shon Gangai
- School of Chemical and Materials Sciences (SCMS), Institute of Technology Goa, Farmagudi, Ponda, Goa 403401, India
| | - Rishikesh Narayan
- School of Chemical and Materials Sciences (SCMS), Institute of Technology Goa, Farmagudi, Ponda, Goa 403401, India
- School of Interdisciplinary Life Sciences (SILS), Institute of Technology Goa, Farmagudi, Ponda, Goa 403401, India
| | - Shobhna Kapoor
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
- IIT-Bombay Monash Academy, Indian Institute of Technology Bombay, Mumbai 400076, India
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8528, Japan
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8
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Kapoor K, Chen T, Tajkhorshid E. Posttranslational modifications optimize the ability of SARS-CoV-2 spike for effective interaction with host cell receptors. Proc Natl Acad Sci U S A 2022; 119:e2119761119. [PMID: 35737823 PMCID: PMC9282386 DOI: 10.1073/pnas.2119761119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/28/2022] [Indexed: 12/31/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein is the prime target for vaccines, diagnostics, and therapeutic antibodies against the virus. While anchored in the viral envelope, for effective virulence, the spike needs to maintain structural flexibility to recognize the host cell surface receptors and bind to them, a property that can heavily depend upon the dynamics of the unresolved domains, most prominently the stalk. Construction of the complete, membrane-bound spike model and the description of its dynamics are critical steps in understanding the inner working of this key element of the viral infection by SARS-CoV-2. Combining homology modeling, protein-protein docking, and molecular dynamics (MD) simulations, we have developed a full spike structure in a native membrane. Multimicrosecond MD simulations of this model, the longest known single trajectory of the full spike, reveal conformational dynamics employed by the protein to explore the surface of the host cell. In agreement with cryogenic electron microscopy (cryo-EM), three flexible hinges in the stalk allow for global conformational heterogeneity of spike in the fully glycosylated system mediated by glycan-glycan and glycan-lipid interactions. The dynamical range of the spike is considerably reduced in its nonglycosylated form, confining the area explored by the spike on the host cell surface. Furthermore, palmitoylation of the membrane domain amplifies the local curvature that may prime the fusion. We show that the identified hinge regions are highly conserved in SARS coronaviruses, highlighting their functional importance in enhancing viral infection, and thereby, provide points for discovery of alternative therapeutics against the virus.
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Affiliation(s)
- Karan Kapoor
- Theoretical and Computational Biophysics Group, NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology, Department of Biochemistry, University of Illinois at Urbana–Champaign, Urbana, IL 61801
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801
| | - Tianle Chen
- Theoretical and Computational Biophysics Group, NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology, Department of Biochemistry, University of Illinois at Urbana–Champaign, Urbana, IL 61801
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801
| | - Emad Tajkhorshid
- Theoretical and Computational Biophysics Group, NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology, Department of Biochemistry, University of Illinois at Urbana–Champaign, Urbana, IL 61801
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801
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9
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Mekhail K, Lee M, Sugiyama M, Astori A, St-Germain J, Latreille E, Khosraviani N, Wei K, Li Z, Rini J, Lee WL, Antonescu C, Raught B, Fairn GD. Fatty Acid Synthase inhibitor TVB-3166 prevents S-acylation of the Spike protein of human coronaviruses. J Lipid Res 2022; 63:100256. [PMID: 35921881 PMCID: PMC9339154 DOI: 10.1016/j.jlr.2022.100256] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/08/2022] [Accepted: 07/09/2022] [Indexed: 11/24/2022] Open
Abstract
The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other coronaviruses mediates host cell entry and is S-acylated on multiple phylogenetically conserved cysteine residues. Multiple protein acyltransferase enzymes have been reported to post-translationally modify spike proteins; however, strategies to exploit this modification are lacking. Using resin-assisted capture MS, we demonstrate that the spike protein is S-acylated in SARS-CoV-2-infected human and monkey epithelial cells. We further show that increased abundance of the acyltransferase ZDHHC5 associates with increased S-acylation of the spike protein, whereas ZDHHC5 knockout cells had a 40% reduction in the incorporation of an alkynyl-palmitate using click chemistry detection. We also found that the S-acylation of the spike protein is not limited to palmitate, as clickable versions of myristate and stearate were also labelled the protein. Yet, we observed that ZDHHC5 was only modified when incubated with alkyne-palmitate, suggesting it has specificity for this acyl-CoA, and that other ZDHHC enzymes may use additional fatty acids to modify the spike protein. Since multiple ZDHHC isoforms may modify the spike protein, we also examined the ability of the FASN inhibitor TVB-3166 to prevent S-acylation of the spike proteins of SARS-CoV-2 and human CoV-229E. We show that treating cells with TVB-3166 inhibited S-acylation of expressed spike proteins and attenuated the ability of SARS-CoV-2 and human CoV-229E to spread in vitro. Our findings further substantiate the necessity of CoV spike protein S-acylation and demonstrate that de novo fatty acid synthesis is critical for the proper S-acylation of the spike protein.
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Affiliation(s)
- Katrina Mekhail
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada
| | - Minhyoung Lee
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada
| | - Michael Sugiyama
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Audrey Astori
- Princess Margaret Cancer Centre, University Health Network, Ontario, Canada
| | | | - Elyse Latreille
- Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Negar Khosraviani
- Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada
| | - Kuiru Wei
- Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada
| | - Zhijie Li
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - James Rini
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Ontario, Canada
| | - Warren L Lee
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada; Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Costin Antonescu
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Brian Raught
- Princess Margaret Cancer Centre, University Health Network, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Ontario, Canada
| | - Gregory D Fairn
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Keenan Research Centre, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada; Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada.
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10
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Ramadan AA, Mayilsamy K, McGill AR, Ghosh A, Giulianotti MA, Donow HM, Mohapatra SS, Mohapatra S, Chandran B, Deschenes RJ, Roy A. Identification of SARS-CoV-2 Spike Palmitoylation Inhibitors That Results in Release of Attenuated Virus with Reduced Infectivity. Viruses 2022; 14:v14030531. [PMID: 35336938 PMCID: PMC8950683 DOI: 10.3390/v14030531] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 02/25/2022] [Accepted: 03/02/2022] [Indexed: 02/02/2023] Open
Abstract
The spike proteins of enveloped viruses are transmembrane glycoproteins that typically undergo post-translational attachment of palmitate on cysteine residues on the cytoplasmic facing tail of the protein. The role of spike protein palmitoylation in virus biogenesis and infectivity is being actively studied as a potential target of novel antivirals. Here, we report that palmitoylation of the first five cysteine residues of the C-terminal cysteine-rich domain of the SARS-CoV-2 S protein are indispensable for infection, and palmitoylation-deficient spike mutants are defective in membrane fusion. The DHHC9 palmitoyltransferase interacts with and palmitoylates the spike protein in the ER and Golgi and knockdown of DHHC9 results in reduced fusion and infection of SARS-CoV-2. Two bis-piperazine backbone-based DHHC9 inhibitors inhibit SARS-CoV-2 S protein palmitoylation and the resulting progeny virion particles released are defective in fusion and infection. This establishes these palmitoyltransferase inhibitors as potential new intervention strategies against SARS-CoV-2.
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Affiliation(s)
- Ahmed A. Ramadan
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
| | - Karthick Mayilsamy
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
- Department of Veterans Affairs, James A Haley Veterans Hospital, Tampa, FL 33612, USA
| | - Andrew R. McGill
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
- Department of Veterans Affairs, James A Haley Veterans Hospital, Tampa, FL 33612, USA
- Department of Internal Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Anandita Ghosh
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
| | - Marc A. Giulianotti
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA; (M.A.G.); (H.M.D.)
| | - Haley M. Donow
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA; (M.A.G.); (H.M.D.)
| | - Shyam S. Mohapatra
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
- Department of Veterans Affairs, James A Haley Veterans Hospital, Tampa, FL 33612, USA
- Department of Internal Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Subhra Mohapatra
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
- Department of Veterans Affairs, James A Haley Veterans Hospital, Tampa, FL 33612, USA
| | - Bala Chandran
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
| | - Robert J. Deschenes
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
- Correspondence: (R.J.D.); (A.R.); Tel.: +1-(813)-974-6393 (R.J.D.); +1-(813)-974-5540 (A.R.)
| | - Arunava Roy
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA; (A.A.R.); (K.M.); (A.R.M.); (A.G.); (S.S.M.); (S.M.); (B.C.)
- Correspondence: (R.J.D.); (A.R.); Tel.: +1-(813)-974-6393 (R.J.D.); +1-(813)-974-5540 (A.R.)
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11
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Lu W, Zhao Z, Huang YW, Wang B. Review: A systematic review of virus-like particles of coronavirus: Assembly, generation, chimerism and their application in basic research and in the clinic. Int J Biol Macromol 2022; 200:487-497. [PMID: 35065135 PMCID: PMC8769907 DOI: 10.1016/j.ijbiomac.2022.01.108] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 12/27/2022]
Abstract
Virus-like particles (VLPs) are nano-scale particles that are morphologically similar to a live virus but which lack a genetic component. Since the pandemic spread of COVID-19, much focus has been placed on coronavirus (CoV)-related VLPs. CoVs contain four structural proteins, though the minimum requirement for VLP formation differs among virus species. CoV VLPs are commonly produced in mammalian and insect cell systems, sometimes in the form of chimeric VLPs that enable surface display of CoV epitopes. VLPs are an ideal model for virological research and have been applied as vaccines and diagnostic reagents to aid in clinical disease control. This review summarizes and updates the research progress on the characteristics of VLPs from different known CoVs, mainly focusing on assembly, in vitro expression systems for VLP generation, VLP chimerism, protein-based nanoparticles and their applications in basic research and clinical settings, which may aid in development of novel VLP vaccines against emerging coronavirus diseases such as SARS-CoV-2.
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Affiliation(s)
- Wan Lu
- Department of Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Zhuangzhuang Zhao
- Department of Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Yao-Wei Huang
- Department of Veterinary Medicine, Zhejiang University, Hangzhou 310058, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China.
| | - Bin Wang
- Department of Veterinary Medicine, Zhejiang University, Hangzhou 310058, China.
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12
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Li X, Shen L, Xu Z, Liu W, Li A, Xu J. Protein Palmitoylation Modification During Viral Infection and Detection Methods of Palmitoylated Proteins. Front Cell Infect Microbiol 2022; 12:821596. [PMID: 35155279 PMCID: PMC8829041 DOI: 10.3389/fcimb.2022.821596] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 01/12/2022] [Indexed: 01/31/2023] Open
Abstract
Protein palmitoylation—a lipid modification in which one or more cysteine thiols on a substrate protein are modified to form a thioester with a palmitoyl group—is a significant post-translational biological process. This process regulates the trafficking, subcellular localization, and stability of different proteins in cells. Since palmitoylation participates in various biological processes, it is related to the occurrence and development of multiple diseases. It has been well evidenced that the proteins whose functions are palmitoylation-dependent or directly involved in key proteins’ palmitoylation/depalmitoylation cycle may be a potential source of novel therapeutic drugs for the related diseases. Many researchers have reported palmitoylation of proteins, which are crucial for host-virus interactions during viral infection. Quite a few explorations have focused on figuring out whether targeting the acylation of viral or host proteins might be a strategy to combat viral diseases. All these remarkable achievements in protein palmitoylation have been made to technological advances. This paper gives an overview of protein palmitoylation modification during viral infection and the methods for palmitoylated protein detection. Future challenges and potential developments are proposed.
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Affiliation(s)
- Xiaoling Li
- College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Lingyi Shen
- College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Zhao Xu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Wei Liu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Aihua Li
- Clinical Lab, Henan Provincial Chest Hospital, Zhengzhou, China
| | - Jun Xu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, China
- *Correspondence: Jun Xu, ;
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13
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Sardar A, Dewangan N, Panda B, Bhowmick D, Tarafdar PK. Lipid and Lipidation in Membrane Fusion. J Membr Biol 2022; 255:691-703. [PMID: 36102950 PMCID: PMC9472184 DOI: 10.1007/s00232-022-00267-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/23/2022] [Indexed: 12/24/2022]
Abstract
Membrane fusion plays a lead role in the transport of vesicles, neurotransmission, mitochondrial dynamics, and viral infection. There are fusion proteins that catalyze and regulate the fusion. Interestingly, various types of fusion proteins are present in nature and they possess diverse mechanisms of action. We have highlighted the importance of the functional domains of intracellular heterotypic fusion, homotypic endoplasmic reticulum (ER), homotypic mitochondrial, and type-I viral fusion. During intracellular heterotypic fusion, the SNAREs and four-helix bundle formation are prevalent. Type-I viral fusion is controlled by the membrane destabilizing properties of fusion peptide and six-helix bundle formation. The ER/mitochondrial homotypic fusion is controlled by GTPase activity and the membrane destabilization properties of the amphipathic helix(s). Although the mechanism of action of these fusion proteins is diverse, they have some similarities. In all cases, the lipid composition of the membrane greatly affects membrane fusion. Next, examples of lipidation of the fusion proteins were discussed. We suggest that the fatty acyl hydrophobic tail not only acts as an anchor but may also modulate the energetics of membrane fusion intermediates. Lipidation is also important to design more effective peptide-based fusion inhibitors. Together, we have shown that membrane lipid composition and lipidation are important to modulate membrane fusion.
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Affiliation(s)
- Avijit Sardar
- grid.417960.d0000 0004 0614 7855Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, West Bengal 741246 India
| | - Nikesh Dewangan
- grid.417960.d0000 0004 0614 7855Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, West Bengal 741246 India
| | - Bishvanwesha Panda
- grid.417960.d0000 0004 0614 7855Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, West Bengal 741246 India
| | - Debosmita Bhowmick
- grid.417960.d0000 0004 0614 7855Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, West Bengal 741246 India
| | - Pradip K. Tarafdar
- grid.417960.d0000 0004 0614 7855Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, West Bengal 741246 India
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14
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Zeng XT, Yu XT, Cheng W. The interactions of ZDHHC5/GOLGA7 with SARS-CoV-2 spike (S) protein and their effects on S protein's subcellular localization, palmitoylation and pseudovirus entry. Virol J 2021; 18:257. [PMID: 34961524 PMCID: PMC8711289 DOI: 10.1186/s12985-021-01722-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/30/2021] [Indexed: 02/08/2023] Open
Abstract
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein determines virus entry and the palmitoylation of S protein affects virus infection. An acyltransferase complex ZDHHC5/GOGAL7 that interacts with S protein was detected by affinity purification mass spectrometry (AP-MS). However, the palmitoylated cysteine residues of S protein, the effects of ZDHHC5 or GOLGA7 knockout on S protein’s subcellular localization, palmitoylation, pseudovirus entry and the enzyme for depalmitoylation of S protein are not clear. Methods The palmitoylated cysteine residues of S protein were identified by acyl-biotin exchange (ABE) assays. The interactions between S protein and host proteins were analyzed by co-immunoprecipitation (co-IP) assays. Subcellular localizations of S protein and host proteins were analyzed by fluorescence microscopy. ZDHHC5 or GOGAL7 gene was edited by CRISPR-Cas9. The entry efficiencies of SARS-CoV-2 pseudovirus into A549 and Hela cells were analyzed by measuring the activity of Renilla luciferase. Results In this investigation, all ten cysteine residues in the endodomain of S protein were palmitoylated. The interaction of S protein with ZDHHC5 or GOLGA7 was confirmed. The interaction and colocalization of S protein with ZDHHC5 or GOLGA7 were independent of the ten cysteine residues in the endodomain of S protein. The interaction between S protein and ZDHHC5 was independent of the enzymatic activity and the PDZ-binding domain of ZDHHC5. Three cell lines HEK293T, A549 and Hela lacking ZDHHC5 or GOLGA7 were constructed. Furthermore, S proteins still interacted with one host protein in HEK293T cells lacking the other. ZDHHC5 or GOLGA7 knockout had no significant effect on S protein’s subcellular localization or palmitoylation, but significantly decreased the entry efficiencies of SARS-CoV-2 pseudovirus into A549 and Hela cells, while varying degrees of entry efficiencies may be linked to the cell types. Additionally, the S protein interacted with the depalmitoylase APT2. Conclusions ZDHHC5 and GOLGA7 played important roles in SARS-CoV-2 pseudovirus entry, but the reason why the two host proteins affected pseudovirus entry remains to be further explored. This study extends the knowledge about the interactions between SARS-CoV-2 S protein and host proteins and probably provides a reference for the corresponding antiviral methods.
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Affiliation(s)
- Xiao-Tao Zeng
- Division of Respiratory and Critical Care Medicine, Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Xiao-Ti Yu
- Division of Respiratory and Critical Care Medicine, Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Wei Cheng
- Division of Respiratory and Critical Care Medicine, Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, 610041, China.
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15
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Identification of ZDHHC17 as a Potential Drug Target for Swine Acute Diarrhea Syndrome Coronavirus Infection. mBio 2021; 12:e0234221. [PMID: 34700373 PMCID: PMC8546599 DOI: 10.1128/mbio.02342-21] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The recent emergence and spread of zoonotic viruses highlights that animal-sourced viruses are the biggest threat to global public health. Swine acute diarrhea syndrome coronavirus (SADS-CoV) is an HKU2-related bat coronavirus that was spilled over from Rhinolophus bats to swine, causing large-scale outbreaks of severe diarrhea disease in piglets in China. Unlike other porcine coronaviruses, SADS-CoV possesses broad species tissue tropism, including primary human cells, implying a significant risk of cross-species spillover. To explore host dependency factors for SADS-CoV as therapeutic targets, we employed genome-wide CRISPR knockout library screening in HeLa cells. Consistent with two independent screens, we identified the zinc finger DHHC-type palmitoyltransferase 17 (ZDHHC17 or ZD17) as an important host factor for SADS-CoV infection. Through truncation mutagenesis, we demonstrated that the DHHC domain of ZD17 that is involved in palmitoylation is important for SADS-CoV infection. Mechanistic studies revealed that ZD17 is required for SADS-CoV genomic RNA replication. Treatment of infected cells with the palmitoylation inhibitor 2-bromopalmitate (2-BP) significantly suppressed SADS-CoV infection. Our findings provide insight on SADS-CoV-host interactions and a potential therapeutic application.
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16
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Mesquita FS, Abrami L, Sergeeva O, Turelli P, Qing E, Kunz B, Raclot C, Paz Montoya J, Abriata LA, Gallagher T, Dal Peraro M, Trono D, D'Angelo G, van der Goot FG. S-acylation controls SARS-CoV-2 membrane lipid organization and enhances infectivity. Dev Cell 2021; 56:2790-2807.e8. [PMID: 34599882 PMCID: PMC8486083 DOI: 10.1016/j.devcel.2021.09.016] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/27/2021] [Accepted: 09/14/2021] [Indexed: 12/28/2022]
Abstract
SARS-CoV-2 virions are surrounded by a lipid bilayer that contains membrane proteins such as spike, responsible for target-cell binding and virus fusion. We found that during SARS-CoV-2 infection, spike becomes lipid modified, through the sequential action of the S-acyltransferases ZDHHC20 and 9. Particularly striking is the rapid acylation of spike on 10 cytosolic cysteines within the ER and Golgi. Using a combination of computational, lipidomics, and biochemical approaches, we show that this massive lipidation controls spike biogenesis and degradation, and drives the formation of localized ordered cholesterol and sphingolipid-rich lipid nanodomains in the early Golgi, where viral budding occurs. Finally, S-acylation of spike allows the formation of viruses with enhanced fusion capacity. Our study points toward S-acylating enzymes and lipid biosynthesis enzymes as novel therapeutic anti-viral targets.
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Affiliation(s)
| | - Laurence Abrami
- Global Health Institute, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Oksana Sergeeva
- Global Health Institute, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Priscilla Turelli
- Global Health Institute, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Enya Qing
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - Béatrice Kunz
- Global Health Institute, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Charlène Raclot
- Global Health Institute, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Jonathan Paz Montoya
- Institute of Bioengineering, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Luciano A Abriata
- Institute of Bioengineering, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Tom Gallagher
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - Matteo Dal Peraro
- Institute of Bioengineering, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Didier Trono
- Global Health Institute, School of Life Sciences, EPFL, Lausanne, Switzerland
| | - Giovanni D'Angelo
- Institute of Bioengineering, School of Life Sciences, EPFL, Lausanne, Switzerland
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Bozdaganyan ME, Orekhov PS, Litvinov DS, Novoseletsky VN. Molecular Modeling of the HR2 and Transmembrane Domains of the SARS-CoV-2 S Protein in the Prefusion State. MOSCOW UNIVERSITY BIOLOGICAL SCIENCES BULLETIN 2021; 76:130-136. [PMID: 34667336 PMCID: PMC8517943 DOI: 10.3103/s0096392521030044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/22/2021] [Accepted: 06/24/2021] [Indexed: 11/30/2022]
Abstract
SARS-CoV-2, the causative agent of COVID-19, remains the focus of research worldwide. SARS-CoV-2 entry into the cell starts with its S protein binding to the angiotensin-converting enzyme-2 (ACE2) expressed on the cell surface. The knowledge of the S protein’s spatial structure is indispensable for understanding the molecular principles of its work. The S protein structure has been almost fully described using experimental approaches with the only exception for the protein’s endodomain, the transmembrane domain, and the ectodomain parts adjacent to the latter. The paper reports molecular modelling of the S protein fragment corresponding to its coiled coil HR2 domain and fully palmitoylated transmembrane domain. Model stability in lipid bilayer was confirmed by all-atom and coarse-grained molecular dynamics simulations. It has been demonstrated that palmitoylation leads to a significant decrease in transmembrane domain mobility and local bilayer thickening, which may be relevant for protein trimerization.
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Affiliation(s)
- M E Bozdaganyan
- Biology Department, Moscow State University, 119234 Moscow, Russia.,Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - P S Orekhov
- Biology Department, Moscow State University, 119234 Moscow, Russia.,Institute of Personalized Medicine, Sechenov University, 119435 Moscow, Russia
| | - D S Litvinov
- Biology Department, Moscow State University, 119234 Moscow, Russia
| | - V N Novoseletsky
- Biology Department, Moscow State University, 119234 Moscow, Russia
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18
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Cell Entry of Animal Coronaviruses. Viruses 2021; 13:v13101977. [PMID: 34696406 PMCID: PMC8540712 DOI: 10.3390/v13101977] [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: 09/10/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 01/11/2023] Open
Abstract
Coronaviruses (CoVs) are a group of enveloped positive-sense RNA viruses and can cause deadly diseases in animals and humans. Cell entry is the first and essential step of successful virus infection and can be divided into two ongoing steps: cell binding and membrane fusion. Over the past two decades, stimulated by the global outbreak of SARS-CoV and pandemic of SARS-CoV-2, numerous efforts have been made in the CoV research. As a result, significant progress has been achieved in our understanding of the cell entry process. Here, we review the current knowledge of this essential process, including the viral and host components involved in cell binding and membrane fusion, molecular mechanisms of their interactions, and the sites of virus entry. We highlight the recent findings of host restriction factors that inhibit CoVs entry. This knowledge not only enhances our understanding of the cell entry process, pathogenesis, tissue tropism, host range, and interspecies-transmission of CoVs but also provides a theoretical basis to design effective preventive and therapeutic strategies to control CoVs infection.
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19
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Li D, Liu Y, Lu Y, Gao S, Zhang L. Palmitoylation of SARS-CoV-2 S protein is critical for S-mediated syncytia formation and virus entry. J Med Virol 2021; 94:342-348. [PMID: 34528721 PMCID: PMC8661603 DOI: 10.1002/jmv.27339] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/07/2021] [Accepted: 09/08/2021] [Indexed: 12/27/2022]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of the ongoing coronavirus disease 2019 (COVID-19) pandemic. The S protein is the key viral protein for associating with ACE2, the receptor for SARS-CoV-2. There are many kinds of posttranslational modifications in S protein. However, the detailed mechanism of palmitoylation of SARS-CoV-2 S remains to be elucidated. In our current study, we characterized the palmitoylation of SARS-CoV-2 S. Both the C15 and cytoplasmic tail of SARS-CoV-2 S were palmitoylated. Fatty acid synthase inhibitor C75 and zinc finger DHHC domain-containing palmitoyltransferase (ZDHHC) inhibitor 2-BP reduced the palmitoylation of S. Interestingly, palmitoylation of SARS-CoV-2 S was not required for plasma membrane targeting of S but was critical for S-mediated syncytia formation and SARS-CoV-2 pseudovirus particle entry. Overexpression of ZDHHC2, ZDHHC3, ZDHHC4, ZDHHC5, ZDHHC8, ZDHHC9, ZDHHC11, ZDHHC14, ZDHHC16, ZDHHC19, and ZDHHC20 promoted the palmitoylation of S. Furthermore, those ZDHHCs were identified to associate with SARS-CoV-2 S. Our study not only reveals the mechanism of S palmitoylation but also will shed important light into the role of S palmitoylation in syncytia formation and virus entry.
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Affiliation(s)
- Daoqun Li
- Department of Clinical Laboratory Medicine, The First Affifiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China.,Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Yihan Liu
- Department of Clinical Laboratory Medicine, The First Affifiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China.,Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Yue Lu
- Department of Clinical Laboratory Medicine, The First Affifiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China.,Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Shan Gao
- Department of Clinical Laboratory Medicine, The First Affifiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China.,Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Leiliang Zhang
- Department of Clinical Laboratory Medicine, The First Affifiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China.,Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.,Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
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20
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Lopes LR. Functional and tissue enrichment analyses suggest that SARS-CoV-2 infection affects host metabolism and catabolism mediated by interference on host proteins. Braz J Microbiol 2021; 52:1151-1159. [PMID: 33956332 PMCID: PMC8099703 DOI: 10.1007/s42770-021-00497-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 04/08/2021] [Indexed: 12/24/2022] Open
Abstract
Infection by SARS-CoV-2, the causative agent of COVID-19, is critically connected with host metabolism. Through functional enrichment analysis, the present study aims to evaluate the biological processes involving host proteins interfered by SARS-CoV-2 to verify the potential metabolic impact of the infection. Furthermore, tissue enrichment analyses and differential gene expression of host proteins were applied to understand the interference by SARS-CoV-2 on tissue levels. Results based on functional and tissue-specific enrichment analyses, presented in this study, suggest that SARS-CoV-2, mediated interference on host proteins, can affect the metabolism and catabolism of molecular building blocks and control intracellular mechanisms, including gene expression in metabolism-related organs, to support viral demands. Thus, SARS-CoV-2 can broadly affect the host metabolism and catabolism at tissue and physiological levels contributing to a more severe disease.
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Affiliation(s)
- Luciano Rodrigo Lopes
- Bioinformatics and Bio-Data Science Division, Health Informatics Department, Universidade Federal de São Paulo-UNIFESP, Rua Botucatu 862 - Prédio Leal Prado (térreo), São Paulo, SP, CEP: 04023-062, Brazil.
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21
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Biochemical composition, transmission and diagnosis of SARS-CoV-2. Biosci Rep 2021; 41:229295. [PMID: 34291285 PMCID: PMC8350435 DOI: 10.1042/bsr20211238] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/19/2021] [Accepted: 07/21/2021] [Indexed: 01/08/2023] Open
Abstract
Coronavirus disease 2019 (COVID-19) is a life-threatening respiratory infection caused by severe acute respiratory syndrome virus (SARS-CoV-2), a novel human coronavirus. COVID-19 was declared a pandemic by World Health Organization in March 2020 for its continuous and rapid spread worldwide. Rapidly emerging COVID-19 epicenters and mutants of concerns have created mammoth chaos in healthcare sectors across the globe. With over 185 million infections and approximately 4 million deaths globally, COVID-19 continues its unchecked spread despite all mitigation measures. Until effective and affordable antiretroviral drugs are made available and the population at large is vaccinated, timely diagnosis of the infection and adoption of COVID-appropriate behavior remains major tool available to curtail the still escalating COVID-19 pandemic. This review provides an updated overview of various techniques of COVID-19 testing in human samples and also discusses, in brief, the biochemical composition and mode of transmission of the SARS-CoV-2. Technological advancement in various molecular, serological and immunological techniques including mainly the reverse-transcription polymerase chain reaction (RT-PCR), CRISPR, lateral flow assays (LFAs), and immunosensors are reviewed.
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22
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Williams CG, Jureka AS, Silvas JA, Nicolini AM, Chvatal SA, Carlson-Stevermer J, Oki J, Holden K, Basler CF. Inhibitors of VPS34 and fatty-acid metabolism suppress SARS-CoV-2 replication. Cell Rep 2021; 36:109479. [PMID: 34320401 PMCID: PMC8289695 DOI: 10.1016/j.celrep.2021.109479] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 03/19/2021] [Accepted: 07/12/2021] [Indexed: 02/06/2023] Open
Abstract
Coronaviruses rely on host membranes for entry, establishment of replication centers, and egress. Compounds targeting cellular membrane biology and lipid biosynthetic pathways have previously shown promise as antivirals and are actively being pursued as treatments for other conditions. Here, we test small molecule inhibitors that target the PI3 kinase VPS34 or fatty acid metabolism for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) activity. Our studies determine that compounds targeting VPS34 are potent SARS-CoV-2 inhibitors. Mechanistic studies with compounds targeting multiple steps up- and downstream of fatty acid synthase (FASN) identify the importance of triacylglycerol production and protein palmitoylation as requirements for efficient viral RNA synthesis and infectious virus production. Further, FASN knockout results in significantly impaired SARS-CoV-2 replication that can be rescued with fatty acid supplementation. Together, these studies clarify roles for VPS34 and fatty acid metabolism in SARS-CoV-2 replication and identify promising avenues for the development of countermeasures against SARS-CoV-2.
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Affiliation(s)
- Caroline G Williams
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Alexander S Jureka
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Jesus A Silvas
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | | | | | | | | | | | - Christopher F Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA.
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23
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Abdulrahman DA, Meng X, Veit M. S-Acylation of Proteins of Coronavirus and Influenza Virus: Conservation of Acylation Sites in Animal Viruses and DHHC Acyltransferases in Their Animal Reservoirs. Pathogens 2021; 10:669. [PMID: 34072434 PMCID: PMC8227752 DOI: 10.3390/pathogens10060669] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/17/2021] [Accepted: 05/25/2021] [Indexed: 01/21/2023] Open
Abstract
Recent pandemics of zoonotic origin were caused by members of coronavirus (CoV) and influenza A (Flu A) viruses. Their glycoproteins (S in CoV, HA in Flu A) and ion channels (E in CoV, M2 in Flu A) are S-acylated. We show that viruses of all genera and from all hosts contain clusters of acylated cysteines in HA, S and E, consistent with the essential function of the modification. In contrast, some Flu viruses lost the acylated cysteine in M2 during evolution, suggesting that it does not affect viral fitness. Members of the DHHC family catalyze palmitoylation. Twenty-three DHHCs exist in humans, but the number varies between vertebrates. SARS-CoV-2 and Flu A proteins are acylated by an overlapping set of DHHCs in human cells. We show that these DHHC genes also exist in other virus hosts. Localization of amino acid substitutions in the 3D structure of DHHCs provided no evidence that their activity or substrate specificity is disturbed. We speculate that newly emerged CoVs or Flu viruses also depend on S-acylation for replication and will use the human DHHCs for that purpose. This feature makes these DHHCs attractive targets for pan-antiviral drugs.
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Affiliation(s)
- Dina A. Abdulrahman
- Department of Virology, Animal Health Research Institute (AHRI), Giza 12618, Egypt;
| | - Xiaorong Meng
- Institute of Virology, Veterinary Faculty, Free University Berlin, 14163 Berlin, Germany;
| | - Michael Veit
- Institute of Virology, Veterinary Faculty, Free University Berlin, 14163 Berlin, Germany;
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24
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Chen JJ, Fan Y, Boehning D. Regulation of Dynamic Protein S-Acylation. Front Mol Biosci 2021; 8:656440. [PMID: 33981723 PMCID: PMC8107437 DOI: 10.3389/fmolb.2021.656440] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/16/2021] [Indexed: 12/20/2022] Open
Abstract
Protein S-acylation is the reversible addition of fatty acids to the cysteine residues of target proteins. It regulates multiple aspects of protein function, including the localization to membranes, intracellular trafficking, protein interactions, protein stability, and protein conformation. This process is regulated by palmitoyl acyltransferases that have the conserved amino acid sequence DHHC at their active site. Although they have conserved catalytic cores, DHHC enzymes vary in their protein substrate selection, lipid substrate preference, and regulatory mechanisms. Alterations in DHHC enzyme function are associated with many human diseases, including cancers and neurological conditions. The removal of fatty acids from acylated cysteine residues is catalyzed by acyl protein thioesterases. Notably, S-acylation is now known to be a highly dynamic process, and plays crucial roles in signaling transduction in various cell types. In this review, we will explore the recent findings on protein S-acylation, the enzymatic regulation of this process, and discuss examples of dynamic S-acylation.
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25
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Zhang M, Han X, Osterrieder K, Veit M. Palmitoylation of the envelope membrane proteins GP5 and M of porcine reproductive and respiratory syndrome virus is essential for virus growth. PLoS Pathog 2021; 17:e1009554. [PMID: 33891658 PMCID: PMC8099100 DOI: 10.1371/journal.ppat.1009554] [Citation(s) in RCA: 4] [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: 11/19/2020] [Revised: 05/05/2021] [Accepted: 04/12/2021] [Indexed: 12/17/2022] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV), an enveloped positive-strand RNA virus in the Arteiviridae family, is a major pathogen affecting pigs worldwide. The membrane (glyco)proteins GP5 and M form a disulfide-linked dimer, which is a major component of virions. GP5/M are required for virus budding, which occurs at membranes of the exocytic pathway. Both GP5 and M feature a short ectodomain, three transmembrane regions, and a long cytoplasmic tail, which contains three and two conserved cysteines, respectively, in close proximity to the transmembrane span. We report here that GP5 and M of PRRSV-1 and -2 strains are palmitoylated at the cysteines, regardless of whether the proteins are expressed individually or in PRRSV-infected cells. To completely prevent S-acylation, all cysteines in GP5 and M have to be exchanged. If individual cysteines in GP5 or M were substituted, palmitoylation was reduced, and some cysteines proved more important for efficient palmitoylation than others. Neither infectious virus nor genome-containing particles could be rescued if all three cysteines present in GP5 or both present in M were replaced in a PRRSV-2 strain, indicating that acylation is essential for virus growth. Viruses lacking one or two acylation sites in M or GP5 could be rescued but grew to significantly lower titers. GP5 and M lacking acylation sites form dimers and GP5 acquires Endo-H resistant carbohydrates in the Golgi apparatus suggesting that trafficking of the membrane proteins to budding sites is not disturbed. Likewise, GP5 lacking two acylation sites is efficiently incorporated into virus particles and these viruses exhibit no reduction in cell entry. We speculate that multiple fatty acids attached to GP5 and M in the endoplasmic reticulum are required for clustering of GP5/M dimers at Golgi membranes and constitute an essential prerequisite for virus assembly. Porcine reproductive and respiratory syndrome virus (PRRSV), an arterivirus in the order Nidovirales, is an important pathogen for pigs. Despite its importance in veterinary medicine, basic structural and functional features of its membrane proteins have not been elucidated. Here, we provide evidence for palmitoylation of the PRRSV major membrane proteins GP5 and M at a cluster of membrane-near cysteines. Fatty acid attachment is required for virus growth, since removal of all acylation sites from either M or GP5 prevents recue of infectious particles. Furthermore, viruses lacking individual acylation sites in M and GP5 grow to significantly lower titers in cell culture. The specific infectivity and cell entry of viruses lacking two acylation sites in Gp5 is, however, not reduced. Likewise, these viruses revealed no effect on dimerization of GP5 with M, its transport to budding sites, and incorporation into virus particles. Since cells transfected with a cDNA expressing non-acylated GP5, or non-acylated M release no virus-like particles into the supernatant we propose that the fatty acids are required for the budding process. They might trigger assembly of GP5/M dimers to form a coat inside the lipid bilayer that induces membrane curvature.
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Affiliation(s)
- Minze Zhang
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
| | - Xiaoliang Han
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Klaus Osterrieder
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
- Department of Infectious Diseases and Public Health, City University of Hong Kong, Kowloon Tong, Hong Kong
| | - Michael Veit
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
- * E-mail:
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26
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Ujike M, Taguchi F. Recent Progress in Torovirus Molecular Biology. Viruses 2021; 13:435. [PMID: 33800523 PMCID: PMC7998386 DOI: 10.3390/v13030435] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/24/2021] [Accepted: 02/24/2021] [Indexed: 11/16/2022] Open
Abstract
Torovirus (ToV) has recently been classified into the new family Tobaniviridae, although it belonged to the Coronavirus (CoV) family historically. ToVs are associated with enteric diseases in animals and humans. In contrast to CoVs, which are recognised as pathogens of veterinary and medical importance, little attention has been paid to ToVs because their infections are usually asymptomatic or not severe; for a long time, only one equine ToV could be propagated in cultured cells. However, bovine ToVs, which predominantly cause diarrhoea in calves, have been detected worldwide, leading to economic losses. Porcine ToVs have also spread globally; although they have not caused serious economic losses, coinfections with other pathogens can exacerbate their symptoms. In addition, frequent inter- or intra-recombination among ToVs can increase pathogenesis or unpredicted host adaptation. These findings have highlighted the importance of ToVs as pathogens and the need for basic ToV research. Here, we review recent progress in the study of ToV molecular biology including reverse genetics, focusing on the similarities and differences between ToVs and CoVs.
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Affiliation(s)
- Makoto Ujike
- Laboratory of Veterinary Infectious Diseases, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan;
- Research Center for Animal Life Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan
| | - Fumihiro Taguchi
- Laboratory of Veterinary Infectious Diseases, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan;
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27
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Main A, Fuller W. Protein S-Palmitoylation: advances and challenges in studying a therapeutically important lipid modification. FEBS J 2021; 289:861-882. [PMID: 33624421 DOI: 10.1111/febs.15781] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/01/2021] [Accepted: 02/22/2021] [Indexed: 12/11/2022]
Abstract
The lipid post-translational modification S-palmitoylation is a vast developing field, with the modification itself and the enzymes that catalyse the reversible reaction implicated in a number of diseases. In this review, we discuss the past and recent advances in the experimental tools used in this field, including pharmacological tools, animal models and techniques to understand how palmitoylation controls protein localisation and function. Additionally, we discuss the obstacles to overcome in order to advance the field, particularly to the point at which modulating palmitoylation may be achieved as a therapeutic strategy.
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Affiliation(s)
- Alice Main
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, UK
| | - William Fuller
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, UK
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28
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Santopolo S, Riccio A, Santoro MG. The biogenesis of SARS-CoV-2 spike glycoprotein: multiple targets for host-directed antiviral therapy. Biochem Biophys Res Commun 2021; 538:80-87. [PMID: 33303190 PMCID: PMC7698684 DOI: 10.1016/j.bbrc.2020.10.080] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 10/28/2020] [Indexed: 12/15/2022]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19 (coronavirus disease-19), represents a far more serious threat to public health than SARS and MERS coronaviruses, due to its ability to spread more efficiently than its predecessors. Currently, there is no worldwide-approved effective treatment for COVID-19, urging the scientific community to intense efforts to accelerate the discovery and development of prophylactic and therapeutic solutions against SARS-CoV-2 infection. In particular, effective antiviral drugs are urgently needed. With few exceptions, therapeutic approaches to combat viral infections have traditionally focused on targeting unique viral components or enzymes; however, it has now become evident that this strategy often fails due to the rapid emergence of drug-resistant viruses. Targeting host factors that are essential for the virus life cycle, but are dispensable for the host, has recently received increasing attention. The spike glycoprotein, a component of the viral envelope that decorates the virion surface as a distinctive crown ("corona") and is essential for SARS-CoV-2 entry into host cells, represents a key target for developing therapeutics capable of blocking virus invasion. This review highlights aspects of the SARS-CoV-2 spike biogenesis that may be amenable to host-directed antiviral targeting.
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Affiliation(s)
- Silvia Santopolo
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Anna Riccio
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - M. Gabriella Santoro
- Department of Biology, University of Rome Tor Vergata, Rome, Italy,Institute of Translational Pharmacology, CNR, Rome, Italy,Corresponding author. Department of Biology, University of Rome Tor Vergata, Rome, Italy
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29
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The Fatty Acid Lipid Metabolism Nexus in COVID-19. Viruses 2021; 13:v13010090. [PMID: 33440724 PMCID: PMC7826519 DOI: 10.3390/v13010090] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/06/2021] [Accepted: 01/07/2021] [Indexed: 02/07/2023] Open
Abstract
Enteric symptomology seen in early-stage severe acute respiratory syndrome (SARS)-2003 and COVID-19 is evidence of virus replication occurring in the intestine, liver and pancreas. Aberrant lipid metabolism in morbidly obese individuals adversely affects the COVID-19 immune response and increases disease severity. Such observations are in line with the importance of lipid metabolism in COVID-19, and point to the gut as a site for intervention as well as a therapeutic target in treating the disease. Formation of complex lipid membranes and palmitoylation of coronavirus proteins are essential during viral replication and assembly. Inhibition of fatty acid synthase (FASN) and restoration of lipid catabolism by activation of AMP-activated protein kinase (AMPK) impede replication of coronaviruses closely related to SARS-coronavirus-2 (CoV-2). In vitro findings and clinical data reveal that the FASN inhibitor, orlistat, and the AMPK activator, metformin, may inhibit coronavirus replication and reduce systemic inflammation to restore immune homeostasis. Such observations, along with the known mechanisms of action for these types of drugs, suggest that targeting fatty acid lipid metabolism could directly inhibit virus replication while positively impacting the patient's response to COVID-19.
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30
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Zhang K, Li S, Pintilie G, Chmielewski D, Schmid MF, Simmons G, Jin J, Chiu W. A 3.4-Å cryo-electron microscopy structure of the human coronavirus spike trimer computationally derived from vitrified NL63 virus particles. QRB DISCOVERY 2020; 1:e11. [PMID: 34192263 PMCID: PMC7737156 DOI: 10.1017/qrd.2020.16] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 11/09/2020] [Accepted: 11/12/2020] [Indexed: 02/06/2023] Open
Abstract
Human coronavirus NL63 (HCoV-NL63) is an enveloped pathogen of the family Coronaviridae that spreads worldwide and causes up to 10% of all annual respiratory diseases. HCoV-NL63 is typically associated with mild upper respiratory symptoms in children, elderly and immunocompromised individuals. It has also been shown to cause severe lower respiratory illness. NL63 shares ACE2 as a receptor for viral entry with SARS-CoV-1 and SARS-CoV-2. Here, we present the in situ structure of HCoV-NL63 spike (S) trimer at 3.4-Å resolution by single-particle cryo-EM imaging of vitrified virions without chemical fixative. It is structurally homologous to that obtained previously from the biochemically purified ectodomain of HCoV-NL63 S trimer, which displays a three-fold symmetric trimer in a single conformation. In addition to previously proposed and observed glycosylation sites, our map shows density at other sites, as well as different glycan structures. The domain arrangement within a protomer is strikingly different from that of the SARS-CoV-2 S and may explain their different requirements for activating binding to the receptor. This structure provides the basis for future studies of spike proteins with receptors, antibodies or drugs, in the native state of the coronavirus particles.
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Affiliation(s)
- Kaiming Zhang
- Department of Bioengineering and James H. Clark Center, Stanford University, Stanford, CA94305, USA
| | - Shanshan Li
- Department of Bioengineering and James H. Clark Center, Stanford University, Stanford, CA94305, USA
| | - Grigore Pintilie
- Department of Bioengineering and James H. Clark Center, Stanford University, Stanford, CA94305, USA
| | - David Chmielewski
- Graduate Program in Biophysics, Stanford University, Stanford, CA94305, USA
| | - Michael F. Schmid
- Division of CryoEM and Bioimaging, SSRL, SLAC National Accelerator Laboratory, Menlo Park, CA94025, USA
| | - Graham Simmons
- Vitalant Research Institute, San Francisco, CA94030, USA
| | - Jing Jin
- Vitalant Research Institute, San Francisco, CA94030, USA
- Division of CryoEM and Bioimaging, SSRL, SLAC National Accelerator Laboratory, Menlo Park, CA94025, USA
| | - Wah Chiu
- Department of Bioengineering and James H. Clark Center, Stanford University, Stanford, CA94305, USA
- Division of CryoEM and Bioimaging, SSRL, SLAC National Accelerator Laboratory, Menlo Park, CA94025, USA
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31
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Abstract
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide since its first incidence in Wuhan, China, in December 2019. Although the case fatality rate of COVID-19 appears to be lower than that of SARS and Middle East respiratory syndrome (MERS), the higher transmissibility of SARS-CoV-2 has caused the total fatality to surpass other viral diseases, reaching more than 1 million globally as of October 6, 2020. The rate at which the disease is spreading calls for a therapy that is useful for treating a large population. Multiple intersecting viral and host factor targets involved in the life cycle of the virus are being explored. Because of the frequent mutations, many coronaviruses gain zoonotic potential, which is dependent on the presence of cell receptors and proteases, and therefore the targeting of the viral proteins has some drawbacks, as strain-specific drug resistance can occur. Moreover, the limited number of proteins in a virus makes the number of available targets small. Although SARS-CoV and SARS-CoV-2 share common mechanisms of entry and replication, there are substantial differences in viral proteins such as the spike (S) protein. In contrast, targeting cellular factors may result in a broader range of therapies, reducing the chances of developing drug resistance. In this Review, we discuss the role of primary host factors such as the cell receptor angiotensin-converting enzyme 2 (ACE2), cellular proteases of S protein priming, post-translational modifiers, kinases, inflammatory cells, and their pharmacological intervention in the infection of SARS-CoV-2 and related viruses.
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Affiliation(s)
- Anil Mathew Tharappel
- Wadsworth Center, New York State Department of Health, 120 New Scotland Ave, Albany, NY 12208, USA
| | - Subodh Kumar Samrat
- Wadsworth Center, New York State Department of Health, 120 New Scotland Ave, Albany, NY 12208, USA
| | - Zhong Li
- Wadsworth Center, New York State Department of Health, 120 New Scotland Ave, Albany, NY 12208, USA
| | - Hongmin Li
- Wadsworth Center, New York State Department of Health, 120 New Scotland Ave, Albany, NY 12208, USA
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, NY 12201, USA
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32
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Casalino L, Gaieb Z, Goldsmith JA, Hjorth CK, Dommer AC, Harbison AM, Fogarty CA, Barros EP, Taylor BC, McLellan JS, Fadda E, Amaro RE. Beyond Shielding: The Roles of Glycans in the SARS-CoV-2 Spike Protein. ACS CENTRAL SCIENCE 2020; 6:1722-1734. [PMID: 33140034 PMCID: PMC7523240 DOI: 10.1021/acscentsci.0c01056] [Citation(s) in RCA: 564] [Impact Index Per Article: 141.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Indexed: 05/04/2023]
Abstract
The ongoing COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in more than 28,000,000 infections and 900,000 deaths worldwide to date. Antibody development efforts mainly revolve around the extensively glycosylated SARS-CoV-2 spike (S) protein, which mediates host cell entry by binding to the angiotensin-converting enzyme 2 (ACE2). Similar to many other viral fusion proteins, the SARS-CoV-2 spike utilizes a glycan shield to thwart the host immune response. Here, we built a full-length model of the glycosylated SARS-CoV-2 S protein, both in the open and closed states, augmenting the available structural and biological data. Multiple microsecond-long, all-atom molecular dynamics simulations were used to provide an atomistic perspective on the roles of glycans and on the protein structure and dynamics. We reveal an essential structural role of N-glycans at sites N165 and N234 in modulating the conformational dynamics of the spike's receptor binding domain (RBD), which is responsible for ACE2 recognition. This finding is corroborated by biolayer interferometry experiments, which show that deletion of these glycans through N165A and N234A mutations significantly reduces binding to ACE2 as a result of the RBD conformational shift toward the "down" state. Additionally, end-to-end accessibility analyses outline a complete overview of the vulnerabilities of the glycan shield of the SARS-CoV-2 S protein, which may be exploited in the therapeutic efforts targeting this molecular machine. Overall, this work presents hitherto unseen functional and structural insights into the SARS-CoV-2 S protein and its glycan coat, providing a strategy to control the conformational plasticity of the RBD that could be harnessed for vaccine development.
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Affiliation(s)
- Lorenzo Casalino
- Department
of Chemistry and Biochemistry, University
of California San Diego, La Jolla, California 92093, United States
| | - Zied Gaieb
- Department
of Chemistry and Biochemistry, University
of California San Diego, La Jolla, California 92093, United States
| | - Jory A. Goldsmith
- Department
of Molecular Biosciences, The University
of Texas at Austin, Austin, Texas 78712, United States
| | - Christy K. Hjorth
- Department
of Molecular Biosciences, The University
of Texas at Austin, Austin, Texas 78712, United States
| | - Abigail C. Dommer
- Department
of Chemistry and Biochemistry, University
of California San Diego, La Jolla, California 92093, United States
| | - Aoife M. Harbison
- Department
of Chemistry and Hamilton Institute, Maynooth
University, Dublin, Ireland
| | - Carl A. Fogarty
- Department
of Chemistry and Hamilton Institute, Maynooth
University, Dublin, Ireland
| | - Emilia P. Barros
- Department
of Chemistry and Biochemistry, University
of California San Diego, La Jolla, California 92093, United States
| | - Bryn C. Taylor
- Department
of Chemistry and Biochemistry, University
of California San Diego, La Jolla, California 92093, United States
- Biomedical
Sciences Graduate Program, University of
California San Diego, La Jolla, California 92093, United States
| | - Jason S. McLellan
- Department
of Molecular Biosciences, The University
of Texas at Austin, Austin, Texas 78712, United States
| | - Elisa Fadda
- Department
of Chemistry and Hamilton Institute, Maynooth
University, Dublin, Ireland
| | - Rommie E. Amaro
- Department
of Chemistry and Biochemistry, University
of California San Diego, La Jolla, California 92093, United States
- Biomedical
Sciences Graduate Program, University of
California San Diego, La Jolla, California 92093, United States
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33
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Casalino L, Gaieb Z, Goldsmith JA, Hjorth CK, Dommer AC, Harbison AM, Fogarty CA, Barros EP, Taylor BC, McLellan JS, Fadda E, Amaro RE. Beyond Shielding: The Roles of Glycans in SARS-CoV-2 Spike Protein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.06.11.146522. [PMID: 32577644 PMCID: PMC7302197 DOI: 10.1101/2020.06.11.146522] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
The ongoing COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in more than 15,000,000 infections and 600,000 deaths worldwide to date. Antibody development efforts mainly revolve around the extensively glycosylated SARS-CoV-2 spike (S) protein, which mediates the host cell entry by binding to the angiotensin-converting enzyme 2 (ACE2). Similar to many other viruses, the SARS-CoV-2 spike utilizes a glycan shield to thwart the host immune response. Here, we built a full-length model of glycosylated SARS-CoV-2 S protein, both in the open and closed states, augmenting the available structural and biological data. Multiple microsecond-long, all-atom molecular dynamics simulations were used to provide an atomistic perspective on the roles of glycans, and the protein structure and dynamics. We reveal an essential structural role of N-glycans at sites N165 and N234 in modulating the conformational dynamics of the spike's receptor binding domain (RBD), which is responsible for ACE2 recognition. This finding is corroborated by biolayer interferometry experiments, which show that deletion of these glycans through N165A and N234A mutations significantly reduces binding to ACE2 as a result of the RBD conformational shift towards the "down" state. Additionally, end-to-end accessibility analyses outline a complete overview of the vulnerabilities of the glycan shield of SARS-CoV-2 S protein, which may be exploited by therapeutic efforts targeting this molecular machine. Overall, this work presents hitherto unseen functional and structural insights into the SARS-CoV-2 S protein and its glycan coat, providing a strategy to control the conformational plasticity of the RBD that could be harnessed for vaccine development.
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Affiliation(s)
- Lorenzo Casalino
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Zied Gaieb
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Jory A. Goldsmith
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Christy K. Hjorth
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Abigail C. Dommer
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Aoife M. Harbison
- Department of Chemistry and Hamilton Institute, Maynooth University, Dublin, Ireland
| | - Carl A. Fogarty
- Department of Chemistry and Hamilton Institute, Maynooth University, Dublin, Ireland
| | - Emilia P. Barros
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Bryn C. Taylor
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA, 92093, USA
| | | | - Elisa Fadda
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
- Department of Chemistry and Hamilton Institute, Maynooth University, Dublin, Ireland
| | - Rommie E. Amaro
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA, 92093, USA
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Requena D, Médico A, Chacón RD, Ramírez M, Marín-Sánchez O. Identification of Novel Candidate Epitopes on SARS-CoV-2 Proteins for South America: A Review of HLA Frequencies by Country. Front Immunol 2020; 11:2008. [PMID: 33013857 PMCID: PMC7494848 DOI: 10.3389/fimmu.2020.02008] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 07/24/2020] [Indexed: 01/08/2023] Open
Abstract
Coronavirus disease (COVID-19), caused by the virus SARS-CoV-2, is already responsible for more than 4.3 million confirmed cases and 295,000 deaths worldwide as of May 15, 2020. Ongoing efforts to control the pandemic include the development of peptide-based vaccines and diagnostic tests. In these approaches, HLA allelic diversity plays a crucial role. Despite its importance, current knowledge of HLA allele frequencies in South America is very limited. In this study, we have performed a literature review of datasets reporting HLA frequencies of South American populations, available in scientific literature and/or in the Allele Frequency Net Database. This allowed us to enrich the current scenario with more than 12.8 million data points. As a result, we are presenting updated HLA allelic frequencies based on country, including 91 alleles that were previously thought to have frequencies either under 5% or of an unknown value. Using alleles with an updated frequency of at least ≥5% in any South American country, we predicted epitopes in SARS-CoV-2 proteins using NetMHCpan (I and II) and MHC flurry. Then, the best predicted epitopes (class-I and -II) were selected based on their binding to South American alleles (Coverage Score). Class II predicted epitopes were also filtered based on their three-dimensional exposure. We obtained 14 class-I and four class-II candidate epitopes with experimental evidence (reported in the Immune Epitope Database and Analysis Resource), having good coverage scores for South America. Additionally, we are presenting 13 HLA-I and 30 HLA-II novel candidate epitopes without experimental evidence, including 16 class-II candidates in highly exposed conserved areas of the NTD and RBD regions of the Spike protein. These novel candidates have even better coverage scores for South America than those with experimental evidence. Finally, we show that recent similar studies presenting candidate epitopes also predicted some of our candidates but discarded them in the selection process, resulting in candidates with suboptimal coverage for South America. In conclusion, the candidate epitopes presented provide valuable information for the development of epitope-based strategies against SARS-CoV-2, such as peptide vaccines and diagnostic tests. Additionally, the updated HLA allelic frequencies provide a better representation of South America and may impact different immunogenetic studies.
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Affiliation(s)
- David Requena
- Laboratory of Cellular Biophysics, The Rockefeller University, New York, NY, United States
| | - Aldhair Médico
- Laboratorio de Bioinformática, Biología Molecular y Desarrollos Tecnológicos, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Ruy D Chacón
- Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Programa Interunidades em Biotecnologia, Universidade de São Paulo, São Paulo, Brazil
| | - Manuel Ramírez
- Unidad de Bioinformática, Centro de Investigaciones Tecnológicas, Biomédicas y Medioambientales, Lima, Peru
| | - Obert Marín-Sánchez
- Departamento Académico de Microbiología Médica, Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Peru
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Zhang K, Li S, Pintilie G, Chmielewski D, Schmid MF, Simmons G, Jin J, Chiu W. A 3.4-Å cryo-EM structure of the human coronavirus spike trimer computationally derived from vitrified NL63 virus particles. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.08.11.245696. [PMID: 32817943 PMCID: PMC7430573 DOI: 10.1101/2020.08.11.245696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Human coronavirus NL63 (HCoV-NL63) is an enveloped pathogen of the family Coronaviridae that spreads worldwide and causes up to 10% of all annual respiratory diseases. HCoV-NL63 is typically associated with mild upper respiratory symptoms in children, elderly and immunocompromised individuals. It has also been shown to cause severe lower respiratory illness. NL63 shares ACE2 as a receptor for viral entry with SARS-CoV and SARS-CoV-2. Here we present the in situ structure of HCoV-NL63 spike (S) trimer at 3.4-Å resolution by single-particle cryo-EM imaging of vitrified virions without chemical fixative. It is structurally homologous to that obtained previously from the biochemically purified ectodomain of HCoV-NL63 S trimer, which displays a 3-fold symmetric trimer in a single conformation. In addition to previously proposed and observed glycosylation sites, our map shows density at other amino acid positions as well as differences in glycan structures. The domain arrangement within a protomer is strikingly different from that of the SARS-CoV-2 S and may explain their different requirements for activating binding to the receptor. This structure provides the basis for future studies of spike proteins with receptors, antibodies, or drugs, in the native state of the coronavirus particles.
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Devi A, Chaitanya NSN. In silico designing of multi-epitope vaccine construct against human coronavirus infections. J Biomol Struct Dyn 2020; 39:6903-6917. [PMID: 32772892 PMCID: PMC7484569 DOI: 10.1080/07391102.2020.1804460] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Single stranded RNA viruses were known to cause variety of diseases since many years and are gaining much importance due to pandemic after the identification of a novel corona virus (severe acute respiratory syndrome-coronavirus (SARS-CoV-2)). Seven coronaviruses (CoVs) are known to infect humans and they are OC43 CoV, NL63 CoV, HKU1 CoV, Middle East respiratory syndrome, SARS CoV, and SARS CoV-2. Virus replication weakens the immune system of host thereby altering T-cell count and much of interferon response. Although no vaccine or therapeutic treatment has been approved till now for CoV infection, trials of vaccine against SARS CoV-2 are in progress. One of the epitopes used for vaccine production is of the spike protein on the surface of virus. The work focuses on designing of multi-epitope vaccine construct for treatment of seven human CoV infections using the epitopes present on the spike protein of human CoVs. To address this, immuno-informatics techniques have been employed to design multi-epitope vaccine construct. B- and T-cell epitopes of the spike proteins have been predicted and designed into a multi-epitope vaccine construct. The tertiary structure of the vaccine construct along with the adjuvant has been modelled and the physiochemical properties have been predicted. The multi-epitope vaccine construct has antigenic and non-allergenic property. After validation, refinement and disulphide engineering of the vaccine construct, molecular docking with toll-like receptors (TLRs) have been performed. Molecular dynamics simulation in aqueous environment predicted that the vaccine-TLRs complexes were stable. The vaccine construct is predicted to be able to trigger primary immune response in silico. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Arpita Devi
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Nyshadham S N Chaitanya
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
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37
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Andreou A, Trantza S, Filippou D, Sipsas N, Tsiodras S. COVID-19: The Potential Role of Copper and N-acetylcysteine (NAC) in a Combination of Candidate Antiviral Treatments Against SARS-CoV-2. In Vivo 2020; 34:1567-1588. [PMID: 32503814 DOI: 10.21873/invivo.11946] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/15/2020] [Accepted: 05/20/2020] [Indexed: 01/08/2023]
Abstract
BACKGROUND On March 11, 2020, the World Health Organization (WHO) declared the outbreak of coronavirus disease (COVID-19) a pandemic. Since then, thousands of people have suffered and died, making the need for a treatment of severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) more crucial than ever. MATERIALS AND METHODS The authors carried out a search in PubMed, ClinicalTrials.gov and New England Journal of Medicine (NEJM) for COVID-19 to provide information on the most promising treatments against SARS-CoV-2. RESULTS Possible COVID-19 agents with promising efficacy and favorable safety profile were identified. The results support the combination of copper, N-acetylcysteine (NAC), colchicine and nitric oxide (NO) with candidate antiviral agents, remdesivir or EIDD-2801, as a treatment for patients positive for SARS-CoV-2. CONCLUSION The authors propose to study the effects of the combination of copper, NAC, colchicine, NO and currently used experimental antiviral agents, remdesivir or EIDD-2801, as a potential treatment scheme for SARS-COV-2.
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Affiliation(s)
- Andri Andreou
- Pharmaceutical Services, Ministry of Health of the Republic of Cyprus, Nicosia, Cyprus
| | | | - Demetrios Filippou
- National Organization for Medicines, Athens, Greece.,Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Nikolaos Sipsas
- Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Sotirios Tsiodras
- Medical School, National and Kapodistrian University of Athens, Athens, Greece
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38
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Abstract
Coronaviruses (CoVs) have caused outbreaks of deadly pneumonia in humans since the beginning of the 21st century. The severe acute respiratory syndrome coronavirus (SARS-CoV) emerged in 2002 and was responsible for an epidemic that spread to five continents with a fatality rate of 10% before being contained in 2003 (with additional cases reported in 2004). The Middle-East respiratory syndrome coronavirus (MERS-CoV) emerged in the Arabian Peninsula in 2012 and has caused recurrent outbreaks in humans with a fatality rate of 35%. SARS-CoV and MERS-CoV are zoonotic viruses that crossed the species barrier using bats/palm civets and dromedary camels, respectively. No specific treatments or vaccines have been approved against any of the six human coronaviruses, highlighting the need to investigate the principles governing viral entry and cross-species transmission as well as to prepare for zoonotic outbreaks which are likely to occur due to the large reservoir of CoVs found in mammals and birds. Here, we review our understanding of the infection mechanism used by coronaviruses derived from recent structural and biochemical studies.
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Affiliation(s)
- M Alejandra Tortorici
- Department of Biochemistry, University of Washington, Seattle, WA, United States; Institut Pasteur, Unité de Virologie Structurale, Paris, France; CNRS UMR 3569, Unité de Virologie Structurale, Paris, France
| | - David Veesler
- Department of Biochemistry, University of Washington, Seattle, WA, United States.
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Naskalska A, Dabrowska A, Nowak P, Szczepanski A, Jasik K, Milewska A, Ochman M, Zeglen S, Rajfur Z, Pyrc K. Novel coronavirus-like particles targeting cells lining the respiratory tract. PLoS One 2018; 13:e0203489. [PMID: 30183777 PMCID: PMC6124810 DOI: 10.1371/journal.pone.0203489] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 08/21/2018] [Indexed: 12/13/2022] Open
Abstract
Virus like particles (VLPs) produced by the expression of viral structural proteins can serve as versatile nanovectors or potential vaccine candidates. In this study we describe for the first time the generation of HCoV-NL63 VLPs using baculovirus system. Major structural proteins of HCoV-NL63 have been expressed in tagged or native form, and their assembly to form VLPs was evaluated. Additionally, a novel procedure for chromatography purification of HCoV-NL63 VLPs was developed. Interestingly, we show that these nanoparticles may deliver cargo and selectively transduce cells expressing the ACE2 protein such as ciliated cells of the respiratory tract. Production of a specific delivery vector is a major challenge for research concerning targeting molecules. The obtained results show that HCoV-NL63 VLPs may be efficiently produced, purified, modified and serve as a delivery platform. This study constitutes an important basis for further development of a promising viral vector displaying narrow tissue tropism.
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Affiliation(s)
- Antonina Naskalska
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
- * E-mail: (AN); (KP)
| | - Agnieszka Dabrowska
- Microbiology Department, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Paulina Nowak
- Microbiology Department, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Artur Szczepanski
- Microbiology Department, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Krzysztof Jasik
- Department of Skin Structural Studies, Medical University of Silesia in Katowice, School of Pharmacy with the Division of Laboratory Medicine, Sosnowiec, Poland
| | - Aleksandra Milewska
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
- Microbiology Department, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Marek Ochman
- Department of Cardiac Surgery and Transplantology, Silesian Center for Heart Diseases, Zabrze, Poland
| | - Slawomir Zeglen
- Department of Cardiac Surgery and Transplantology, Silesian Center for Heart Diseases, Zabrze, Poland
| | - Zenon Rajfur
- Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Sciences, Jagiellonian University, Krakow, Poland
| | - Krzysztof Pyrc
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
- Microbiology Department, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
- * E-mail: (AN); (KP)
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40
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Fung TS, Liu DX. Post-translational modifications of coronavirus proteins: roles and function. Future Virol 2018; 13:405-430. [PMID: 32201497 PMCID: PMC7080180 DOI: 10.2217/fvl-2018-0008] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 04/13/2018] [Indexed: 12/22/2022]
Abstract
Post-translational modifications (PTMs) refer to the covalent modifications of polypeptides after they are synthesized, adding temporal and spatial regulation to modulate protein functions. Being obligate intracellular parasites, viruses rely on the protein synthesis machinery of host cells to support replication, and not surprisingly, many viral proteins are subjected to PTMs. Coronavirus (CoV) is a group of enveloped RNA viruses causing diseases in both human and animals. Many CoV proteins are modified by PTMs, including glycosylation and palmitoylation of the spike and envelope protein, N- or O-linked glycosylation of the membrane protein, phosphorylation and ADP-ribosylation of the nucleocapsid protein, and other PTMs on nonstructural and accessory proteins. In this review, we summarize the current knowledge on PTMs of CoV proteins, with an emphasis on their impact on viral replication and pathogenesis. The ability of some CoV proteins to interfere with PTMs of host proteins will also be discussed.
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Affiliation(s)
- To Sing Fung
- South China Agricultural University, Guangdong Province Key Laboratory Microbial Signals & Disease Co, & Integrative Microbiology Research Center, Guangzhou 510642, Guangdong, PR China.,South China Agricultural University, Guangdong Province Key Laboratory Microbial Signals & Disease Co, & Integrative Microbiology Research Center, Guangzhou 510642, Guangdong, PR China
| | - Ding Xiang Liu
- South China Agricultural University, Guangdong Province Key Laboratory Microbial Signals & Disease Co, & Integrative Microbiology Research Center, Guangzhou 510642, Guangdong, PR China.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.,South China Agricultural University, Guangdong Province Key Laboratory Microbial Signals & Disease Co, & Integrative Microbiology Research Center, Guangzhou 510642, Guangdong, PR China.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
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41
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Abstract
Coronavirus particles serve three fundamentally important functions in infection. The virion provides the means to deliver the viral genome across the plasma membrane of a host cell. The virion is also a means of escape for newly synthesized genomes. Lastly, the virion is a durable vessel that protects the genome on its journey between cells. This review summarizes the available X-ray crystallography, NMR, and cryoelectron microscopy structural data for coronavirus structural proteins, and looks at the role of each of the major structural proteins in virus entry and assembly. The potential wider conservation of the nucleoprotein fold identified in the Arteriviridae and Coronaviridae families and a speculative model for the evolution of corona-like virus architecture are discussed.
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Affiliation(s)
- B W Neuman
- School of Biological Sciences, University of Reading, Reading, United Kingdom; College of STEM, Texas A&M University, Texarkana, Texarkana, TX, United States.
| | - M J Buchmeier
- University of California, Irvine, Irvine, CA, United States
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42
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Ujike M, Taguchi F. Incorporation of spike and membrane glycoproteins into coronavirus virions. Viruses 2015; 7:1700-25. [PMID: 25855243 PMCID: PMC4411675 DOI: 10.3390/v7041700] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 03/23/2015] [Accepted: 03/24/2015] [Indexed: 12/15/2022] Open
Abstract
The envelopes of coronaviruses (CoVs) contain primarily three proteins; the two major glycoproteins spike (S) and membrane (M), and envelope (E), a non-glycosylated protein. Unlike other enveloped viruses, CoVs bud and assemble at the endoplasmic reticulum (ER)-Golgi intermediate compartment (ERGIC). For efficient virion assembly, these proteins must be targeted to the budding site and to interact with each other or the ribonucleoprotein. Thus, the efficient incorporation of viral envelope proteins into CoV virions depends on protein trafficking and protein–protein interactions near the ERGIC. The goal of this review is to summarize recent findings on the mechanism of incorporation of the M and S glycoproteins into the CoV virion, focusing on protein trafficking and protein–protein interactions.
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Affiliation(s)
- Makoto Ujike
- Laboratory of Virology and Viral Infections, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan.
| | - Fumihiro Taguchi
- Laboratory of Virology and Viral Infections, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan.
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43
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Palmitoylation of the Alphacoronavirus TGEV spike protein S is essential for incorporation into virus-like particles but dispensable for S-M interaction. Virology 2014; 464-465:397-405. [PMID: 25113909 PMCID: PMC7112097 DOI: 10.1016/j.virol.2014.07.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 05/18/2014] [Accepted: 07/21/2014] [Indexed: 01/30/2023]
Abstract
The spike protein S of coronaviruses contains a highly conserved cytoplasmic cysteine-rich motif adjacent to the transmembrane region. This motif is palmitoylated in the Betacoronaviruses MHV and SARS-CoV. Here, we demonstrate by metabolic labeling with [(3)H]-palmitic acid that the S protein of transmissible gastroenteritis coronavirus (TGEV), an Alphacoronavirus, is palmitoylated as well. This is relevant for TGEV replication as virus growth was compromised by the general palmitoylation inhibitor 2-bromopalmitate. Mutation of individual cysteine clusters in the cysteine-rich motif of S revealed that all cysteines must be replaced to abolish acylation and incorporation of S into virus-like particles (VLP). Conversely, the interaction of S with the M protein, essential for VLP incorporation of S, was not impaired by lack of palmitoylation. Thus, palmitoylation of the S protein of Alphacoronaviruses is dispensable for S-M interaction, but required for the generation of progeny virions.
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44
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De novo fatty acid biosynthesis contributes significantly to establishment of a bioenergetically favorable environment for vaccinia virus infection. PLoS Pathog 2014; 10:e1004021. [PMID: 24651651 PMCID: PMC3961357 DOI: 10.1371/journal.ppat.1004021] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 02/06/2014] [Indexed: 12/17/2022] Open
Abstract
The poxvirus life cycle, although physically autonomous from the host nucleus, is nevertheless dependent upon cellular functions. A requirement for de novo fatty acid biosynthesis was implied by our previous demonstration that cerulenin, a fatty acid synthase inhibitor, impaired vaccinia virus production. Here we show that additional inhibitors of this pathway, TOFA and C75, reduce viral yield significantly, with partial rescue provided by exogenous palmitate, the pathway's end-product. Palmitate's major role during infection is not for phospholipid synthesis or protein palmitoylation. Instead, the mitochondrial import and β-oxidation of palmitate are essential, as shown by the impact of etomoxir and trimetazidine, which target these two processes respectively. Moreover, the impact of these inhibitors is exacerbated in the absence of exogenous glucose, which is otherwise dispensable for infection. In contrast to glucose, glutamine is essential for productive viral infection, providing intermediates that sustain the TCA cycle (anaplerosis). Cumulatively, these data suggest that productive infection requires the mitochondrial β-oxidation of palmitate which drives the TCA cycle and energy production. Additionally, infection causes a significant rise in the cellular oxygen consumption rate (ATP synthesis) that is ablated by etomoxir. The biochemical progression of the vaccinia life cycle is not impaired in the presence of TOFA, C75, or etomoxir, although the levels of viral DNA and proteins synthesized are somewhat diminished. However, by reversibly arresting infections at the onset of morphogenesis, and then monitoring virus production after release of the block, we determined that virion assembly is highly sensitive to TOFA and C75. Electron microscopic analysis of cells released into C75 revealed fragmented aggregates of viroplasm which failed to be enclosed by developing virion membranes. Taken together, these data indicate that vaccinia infection, and in particular virion assembly, relies on the synthesis and mitochondrial import of fatty acids, where their β-oxidation drives robust ATP production. Vaccinia virus, the prototypic poxvirus, is closely related to variola virus, the etiological agent of smallpox. A full understanding of the poxviral life cycle is imperative for the development of novel antiviral therapies, the design of new vaccines, and the effective and safe use of these viruses as oncolytic agents. Metabolomic studies have shed light on the novel mechanisms used by viruses to replicate efficiently within their hosts. de novo fatty acid biosynthesis has been shown to be of relevance for numerous viral infections as well as for the development of cancer. Here we describe an important role for de novo fatty acid biosynthesis during vaccinia infection. Ongoing synthesis of palmitate is needed to fuel the production of energy within mitochondria. The biochemical events of viral DNA replication and protein synthesis are minimally affected by inhibition of this pathway, but viral assembly is disrupted more dramatically. Further exploration of this pathway will provide additional insight into the infectious cycle and inform new therapeutic strategies for this important class of pathogen.
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45
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Negatively charged residues in the endodomain are critical for specific assembly of spike protein into murine coronavirus. Virology 2013; 442:74-81. [PMID: 23628137 PMCID: PMC3772176 DOI: 10.1016/j.virol.2013.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 04/01/2013] [Accepted: 04/01/2013] [Indexed: 01/17/2023]
Abstract
Coronavirus spike (S) protein assembles into virions via its carboxy-terminus, which is composed of a transmembrane domain and an endodomain. Here, the carboxy-terminal charge-rich motif in the endodomain was verified to be critical for the specificity of S assembly into mouse hepatitis virus (MHV). Recombinant MHVs exhibited a range of abilities to accommodate the homologous S endodomains from the betacoronaviruses bovine coronavirus and human SARS-associated coronavirus, the alphacoronavirus porcine transmissible gastroenteritis virus (TGEV), and the gammacoronavirus avian infectious bronchitis virus respectively. Interestingly, in TGEV endodomain chimeras the reverting mutations resulted in stronger S incorporation into virions, and a net gain of negatively charged residues in the charge-rich motif accounted for the improvement. Additionally, MHV S assembly could also be rescued by the acidic carboxy-terminal domain of the nucleocapsid protein. These results indicate an important role for negatively charged endodomain residues in the incorporation of MHV S protein into assembled virions. Charge-rich motif in endodomain is a major determinant for coronavirus S assembly. MHV exhibited different accommodations to S endodomains from other coronaviruses. MHV with TGEV S endodomain improved S incorporation by reverting mutation. MHV S assembly could be partial restored by acidic carboxy-terminal domain of N. Negatively charged residues in endodomain are critical for S specific assembly.
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46
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Expression and purification of coronavirus envelope proteins using a modified β-barrel construct. Protein Expr Purif 2012; 85:133-41. [PMID: 22819936 PMCID: PMC7129850 DOI: 10.1016/j.pep.2012.07.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 07/11/2012] [Accepted: 07/11/2012] [Indexed: 11/24/2022]
Abstract
Coronavirus envelope (E) proteins are short (~100 residues) polypeptides that contain at least one transmembrane (TM) domain and a cluster of 2-3 juxtamembrane cysteines. These proteins are involved in viral morphogenesis and tropism, and their absence leads in some cases to aberrant virions, or to viral attenuation. In common to other viroporins, coronavirus envelope proteins increase membrane permeability to ions. Although an NMR-based model for the TM domain of the E protein in the severe acute respiratory syndrome virus (SARS-CoV E) has been reported, structural data and biophysical studies of full length E proteins are not available because efficient expression and purification methods for these proteins are lacking. Herein we have used a novel fusion protein consisting of a modified β-barrel to purify both wild type and cysteine-less mutants of two representatives of coronavirus E proteins: the shortest (76 residues), from SARS-CoV E, and one of the longest (109 residues), from the infectious bronchitis virus (IBV E). The fusion construct was subsequently cleaved with cyanogen bromide and all polypeptides were obtained with high purity. This is an approach that can be used in other difficult hydrophobic peptides.
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47
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Abstract
The article summarises the results of more than 30 years of research on palmitoylation (S‐acylation) of viral proteins, the post‐translational attachment of fatty acids to cysteine residues of integral and peripheral membrane proteins. Analysing viral proteins is not only important to characterise the cellular pathogens but also instrumental to decipher the palmitoylation machinery of cells. This comprehensive review describes methods to identify S‐acylated proteins and covers the fundamental biochemistry of palmitoylation: the location of palmitoylation sites in viral proteins, the fatty acid species found in S‐acylated proteins, the intracellular site of palmitoylation and the enzymology of the reaction. Finally, the functional consequences of palmitoylation are discussed regarding binding of proteins to membranes or membrane rafts, entry of enveloped viruses into target cells by spike‐mediated membrane fusion as well as assembly and release of virus particles from infected cells. The topics are described mainly for palmitoylated proteins of influenza virus, but proteins of other important pathogens, such as the causative agents of AIDS and severe acute respiratory syndrome, and of model viruses are discussed.
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Affiliation(s)
- Michael Veit
- Department of Immunology and Molecular Biology, Free University, Berlin, Germany.
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48
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Yang J, Lv J, Wang Y, Gao S, Yao Q, Qu D, Ye R. Replication of murine coronavirus requires multiple cysteines in the endodomain of spike protein. Virology 2012; 427:98-106. [PMID: 22424735 PMCID: PMC7111998 DOI: 10.1016/j.virol.2012.02.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Revised: 01/04/2012] [Accepted: 02/23/2012] [Indexed: 01/03/2023]
Abstract
A conserved cysteine-rich motif located between the transmembrane domain and the endodomain is essential for membrane fusion and assembly of coronavirus spike (S) protein. Here, we proved that three cysteines within the motif, but not dependent on position, are minimally required for the survival of the recombinant mouse hepatitis virus. When the carboxy termini with these mutated motifs of S proteins were respectively introduced into a heterogeneous protein, both incorporation into lipid rafts and S-palmitoylation of these recombinant proteins showed a similar quantity requirement to cysteine residues. Meanwhile, the redistribution of these proteins on cellular surface indicated that the absence of the positively charged rather than cysteine residues in the motif might lead the dramatic reduction in syncytial formation of some mutants with the deleted motifs. These results suggest that multiple cysteine as well as charged residues concurrently improves the membrane-associated functions of S protein in viral replication and cytopathogenesis.
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Affiliation(s)
- Jinhua Yang
- Shanghai Medical College, Fudan University, Shanghai 200032, China
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Ujike M, Huang C, Shirato K, Matsuyama S, Makino S, Taguchi F. Two palmitylated cysteine residues of the severe acute respiratory syndrome coronavirus spike (S) protein are critical for S incorporation into virus-like particles, but not for M-S co-localization. J Gen Virol 2012; 93:823-828. [PMID: 22238235 DOI: 10.1099/vir.0.038091-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The endodomain of several coronavirus (CoV) spike (S) proteins contains palmitylated cysteine residues and enables co-localization and interaction with the CoV membrane (M) protein. Depalmitylation of mouse hepatitis virus S proteins abolished this interaction, resulting in the failure of S incorporation into virions. In contrast, an immunofluorescence assay (IFA) showed that depalmitylated severe acute respiratory syndrome coronavirus (SCoV) S proteins still co-localized with the M protein in the budding site. Here, we determined the ability of depalmitylated SCoV S mutants to incorporate S into virus-like particles (VLPs). IFA confirmed that all SCoV S mutants co-localized with the M protein intracellularly. However, the mutants lacking two cysteine residues (C(1234/1235)) failed to incorporate S into VLPs. This indicated that these palmitylated cysteines are essential for S incorporation, but are not involved in S co-localization mediated by the M protein. Our findings suggest that M-S co-localization and S incorporation occur independently of one another in SCoV virion assembly.
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Affiliation(s)
- Makoto Ujike
- Laboratory of Virology and Viral Infections, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan
| | - Cheng Huang
- Department of Microbiology and Immunology, The University of Texas Medical Branch at Galveston, Galveston, TX 77555-1019, USA
| | - Kazuya Shirato
- Department of Virology III, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan
| | - Shutoku Matsuyama
- Department of Virology III, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan
| | - Shinji Makino
- Department of Microbiology and Immunology, The University of Texas Medical Branch at Galveston, Galveston, TX 77555-1019, USA
| | - Fumihiro Taguchi
- Laboratory of Virology and Viral Infections, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan
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Mutating conserved cysteines in the alphavirus e2 glycoprotein causes virus-specific assembly defects. J Virol 2012; 86:3100-11. [PMID: 22238319 DOI: 10.1128/jvi.06615-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
There are 80 trimeric, glycoprotein spikes that cover the surface of an alphavirus particle. The spikes, which are composed of three E2 and E1 glycoprotein heterodimers, are responsible for receptor binding and mediating fusion between the viral and host-cell membranes during entry. In addition, the cytoplasmic domain of E2 interacts with the nucleocapsid core during the last stages of particle assembly, possibly to aid in particle stability. During assembly, the spikes are nonfusogenic until the E3 glycoprotein is cleaved from E2 in the trans-Golgi network. Thus, a mutation in E2 potentially has effects on virus entry, spike assembly, or spike maturation. E2 is a highly conserved, cysteine-rich transmembrane glycoprotein. We made single cysteine-to-serine mutations within two distinct regions of the E2 ectodomain in both Sindbis virus and Ross River virus. Each of the E2 Cys mutants produced fewer infectious particles than wild-type virus. Further characterization of the mutant viruses revealed differences in particle morphology, fusion activity, and polyprotein cleavage between Sindbis and Ross River virus mutants, despite the mutations being made at corresponding positions in E2. The nonconserved assembly defects suggest that E2 folding and function is species dependent, possibly due to interactions with a virus-specific chaperone.
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