1
|
Das PK, Gonzalez PA, Jangra RK, Yin P, Kielian M. A single-point mutation in the rubella virus E1 glycoprotein promotes rescue of recombinant vesicular stomatitis virus. mBio 2024; 15:e0237323. [PMID: 38334805 PMCID: PMC10936182 DOI: 10.1128/mbio.02373-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 01/10/2024] [Indexed: 02/10/2024] Open
Abstract
Rubella virus (RuV) is an enveloped plus-sense RNA virus and a member of the Rubivirus genus. RuV infection in pregnant women can lead to miscarriage or an array of severe birth defects known as congenital rubella syndrome. Novel rubiviruses were recently discovered in various mammals, highlighting the spillover potential of other rubiviruses to humans. Many features of the rubivirus infection cycle remain unexplored. To promote the study of rubivirus biology, here, we generated replication-competent recombinant VSV-RuV (rVSV-RuV) encoding the RuV transmembrane glycoproteins E2 and E1. Sequencing of rVSV-RuV showed that the RuV glycoproteins acquired a single-point mutation W448R in the E1 transmembrane domain. The E1 W448R mutation did not detectably alter the intracellular expression, processing, glycosylation, colocalization, or dimerization of the E2 and E1 glycoproteins. Nonetheless, the mutation enhanced the incorporation of RuV E2/E1 into VSV particles, which bud from the plasma membrane rather than the RuV budding site in the Golgi. Neutralization by E1 antibodies, calcium dependence, and cell tropism were comparable between WT-RuV and either rVSV-RuV or RuV containing the E1 W448R mutation. However, the E1 W448R mutation strongly shifted the threshold for the acid pH-triggered virus fusion reaction, from pH 6.2 for the WT RuV to pH 5.5 for the mutant. These results suggest that the increased resistance of the mutant RuV E1 to acidic pH promotes the ability of viral envelope proteins to generate infectious rVSV and provide insights into the regulation of RuV fusion during virus entry and exit.IMPORTANCERubella virus (RuV) infection in pregnant women can cause miscarriage or severe fetal birth defects. While a highly effective vaccine has been developed, RuV cases are still a significant problem in areas with inadequate vaccine coverage. In addition, related viruses have recently been discovered in mammals, such as bats and mice, leading to concerns about potential virus spillover to humans. To facilitate studies of RuV biology, here, we generated and characterized a replication-competent vesicular stomatitis virus encoding the RuV glycoproteins (rVSV-RuV). Sequence analysis of rVSV-RuV identified a single-point mutation in the transmembrane region of the E1 glycoprotein. While the overall properties of rVSV-RuV are similar to those of WT-RuV, the mutation caused a marked shift in the pH dependence of virus membrane fusion. Together, our studies of rVSV-RuV and the identified W448R mutation expand our understanding of rubivirus biology and provide new tools for its study.
Collapse
Affiliation(s)
- Pratyush Kumar Das
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, USA
| | | | - Rohit K. Jangra
- Department of Microbiology and Immunology, Louisiana State University Health Science Center-Shreveport, Shreveport, Louisiana, USA
| | - Peiqi Yin
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Margaret Kielian
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, USA
| |
Collapse
|
2
|
Abstract
There are at least 21 families of enveloped viruses that infect mammals, and many contain members of high concern for global human health. All enveloped viruses have a dedicated fusion protein or fusion complex that enacts the critical genome-releasing membrane fusion event that is essential before viral replication within the host cell interior can begin. Because all enveloped viruses enter cells by fusion, it behooves us to know how viral fusion proteins function. Viral fusion proteins are also major targets of neutralizing antibodies, and hence they serve as key vaccine immunogens. Here we review current concepts about viral membrane fusion proteins focusing on how they are triggered, structural intermediates between pre- and postfusion forms, and their interplay with the lipid bilayers they engage. We also discuss cellular and therapeutic interventions that thwart virus-cell membrane fusion.
Collapse
Affiliation(s)
- Judith M White
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia, USA;
| | - Amanda E Ward
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, Virginia, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Laura Odongo
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, Virginia, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Lukas K Tamm
- Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, Virginia, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| |
Collapse
|
3
|
Randhawa K, Jahani-Asl A. CLIC1 regulation of cancer stem cells in glioblastoma. CURRENT TOPICS IN MEMBRANES 2023; 92:99-123. [PMID: 38007271 DOI: 10.1016/bs.ctm.2023.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
Chloride intracellular channel 1 (CLIC1) has emerged as a therapeutic target in various cancers. CLIC1 promotes cell cycle progression and cancer stem cell (CSC) self-renewal. Furthermore, CLIC1 is shown to play diverse roles in proliferation, cell volume regulation, tumour invasion, migration, and angiogenesis. In glioblastoma (GB), CLIC1 facilitates the G1/S phase transition and tightly regulates glioma stem-like cells (GSCs), a rare population of self-renewing CSCs with central roles in tumour resistance to therapy and tumour recurrence. CLIC1 is found as either a monomeric soluble protein or as a non-covalent dimeric protein that can form an ion channel. The ratio of dimeric to monomeric protein is altered in GSCs and depends on the cell redox state. Elucidating the mechanisms underlying the alterations in CLIC1 expression and structural transitions will further our understanding of its role in GSC biology. This review will highlight the role of CLIC1 in GSCs and its significance in facilitating different hallmarks of cancer.
Collapse
Affiliation(s)
- Kamaldeep Randhawa
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada; Brain and Mind Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - Arezu Jahani-Asl
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada; Brain and Mind Research Institute, University of Ottawa, Ottawa, ON, Canada; Regenerative Medicine Program and Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada.
| |
Collapse
|
4
|
Yin P, Davenport BJ, Wan JJ, Kim AS, Diamond MS, Ware BC, Tong K, Couderc T, Lecuit M, Lai JR, Morrison TE, Kielian M. Chikungunya virus cell-to-cell transmission is mediated by intercellular extensions in vitro and in vivo. Nat Microbiol 2023; 8:1653-1667. [PMID: 37591996 PMCID: PMC10956380 DOI: 10.1038/s41564-023-01449-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 07/13/2023] [Indexed: 08/19/2023]
Abstract
Chikungunya virus (CHIKV) has recently emerged to cause millions of human infections worldwide. Infection can induce the formation of long intercellular extensions that project from infected cells and form stable non-continuous membrane bridges with neighbouring cells. The mechanistic role of these intercellular extensions in CHIKV infection was unclear. Here we developed a co-culture system and flow cytometry methods to quantitatively evaluate transmission of CHIKV from infected to uninfected cells in the presence of neutralizing antibody. Endocytosis and endosomal acidification were critical for virus cell-to-cell transmission, while the CHIKV receptor MXRA8 was not. By using distinct antibodies to block formation of extensions and by evaluation of transmission in HeLa cells that did not form extensions, we showed that intercellular extensions mediate CHIKV cell-to-cell transmission. In vivo, pre-treatment of mice with a neutralizing antibody blocked infection by direct virus inoculation, while adoptive transfer of infected cells produced antibody-resistant host infection. Together our data suggest a model in which the contact sites of intercellular extensions on target cells shield CHIKV from neutralizing antibodies and promote efficient intercellular virus transmission both in vitro and in vivo.
Collapse
Affiliation(s)
- Peiqi Yin
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Bennett J Davenport
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Judy J Wan
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Arthur S Kim
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
- Department of Pathology & Immunology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
- Department of Pathology & Immunology, Washington University School of Medicine, Saint Louis, MO, USA
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Brian C Ware
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Karen Tong
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Thérèse Couderc
- Institut Pasteur, Inserm U1117, Biology of Infection Unit, Université de Paris, Paris, France
| | - Marc Lecuit
- Institut Pasteur, Inserm U1117, Biology of Infection Unit, Université de Paris, Paris, France
- Department of Infectious Diseases and Tropical Medicine, APHP, Institut Imagine, Necker-Enfants Malades University Hospital, Paris, France
| | - Jonathan R Lai
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Thomas E Morrison
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Margaret Kielian
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, USA.
| |
Collapse
|
5
|
Membrane Sphingomyelin in Host Cells Is Essential for Nucleocapsid Penetration into the Cytoplasm after Hemifusion during Rubella Virus Entry. mBio 2022; 13:e0169822. [PMID: 36346228 PMCID: PMC9765692 DOI: 10.1128/mbio.01698-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The lipid composition of the host cell membrane is one of the key determinants of the entry of enveloped viruses into cells. To elucidate the detailed mechanisms behind the cell entry of rubella virus (RuV), one of the enveloped viruses, we searched for host factors involved in such entry by using CRISPR/Cas9 genome-wide knockout screening, and we found sphingomyelin synthase 1 (SMS1), encoded by the SGMS1 gene, as a candidate. RuV growth was strictly suppressed in SGMS1-knockout cells and was completely recovered by the overexpression of enzymatically active SMS1 and partially recovered by that of SMS2, another member of the SMS family, but not by that of enzymatically inactive SMS1. An entry assay using pseudotyped vesicular stomatitis virus possessing RuV envelope proteins revealed that sphingomyelin generated by SMSs is crucial for at least RuV entry. In SGMS1-knockout cells, lipid mixing between the RuV envelope membrane and the membrane of host cells occurred, but entry of the RuV genome from the viral particles into the cytoplasm was strongly inhibited. This indicates that sphingomyelin produced by SMSs is essential for the formation of membrane pores after hemifusion occurs during RuV entry. IMPORTANCE Infection with rubella virus during pregnancy causes congenital rubella syndrome in infants. Despite its importance in public health, the detailed mechanisms of rubella virus cell entry have only recently become somewhat clearer. The E1 protein of rubella virus is classified as a class II fusion protein based on its structural similarity, but it has the unique feature that its activity is dependent on calcium ion binding in the fusion loops. In this study, we found another unique feature, as cellular sphingomyelin plays a critical role in the penetration of the nucleocapsid into the cytoplasm after hemifusion by rubella virus. This provides important insight into the entry mechanism of rubella virus. This study also presents a model of hemifusion arrest during cell entry by an intact virus, providing a useful tool for analyzing membrane fusion, a biologically important phenomenon.
Collapse
|
6
|
Varela L, Hendry AC, Cassar J, Martin-Escolano R, Cantoni D, Ossa F, Edwards JC, Abdul-Salam V, Ortega-Roldan JL. Zn2+ triggered two-step mechanism of CLIC1 membrane insertion and activation into chloride channels. J Cell Sci 2022; 135:276009. [PMID: 35833483 PMCID: PMC9511705 DOI: 10.1242/jcs.259704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 07/04/2022] [Indexed: 11/21/2022] Open
Abstract
The chloride intracellular channel (CLIC) protein family displays the unique feature of altering its structure from a soluble form to a membrane-bound chloride channel. CLIC1, a member of this family, is found in the cytoplasm or in internal and plasma membranes, with membrane relocalisation linked to endothelial disfunction, tumour proliferation and metastasis. The molecular switch promoting CLIC1 activation remains under investigation. Here, cellular Cl− efflux assays and immunofluorescence microscopy studies have identified intracellular Zn2+ release as the trigger for CLIC1 activation and membrane insertion. Biophysical assays confirmed specific binding to Zn2+, inducing membrane association and enhancing Cl− efflux in a pH-dependent manner. Together, our results identify a two-step mechanism with Zn2+ binding as the molecular switch promoting CLIC1 membrane insertion, followed by pH-mediated activation of Cl− efflux. Summary: Identification of a two-step mechanism of CLIC1 membrane insertion based on Zn2+ binding and pH activation of Cl− efflux.
Collapse
Affiliation(s)
- Lorena Varela
- School of Biosciences. University of Kent. CT2 7NJ. Canterbury, UK
| | - Alex C Hendry
- School of Biosciences. University of Kent. CT2 7NJ. Canterbury, UK
| | - Joseph Cassar
- School of Biosciences. University of Kent. CT2 7NJ. Canterbury, UK
| | | | - Diego Cantoni
- Medway School of Pharmacy, The Universities of Kent and Greenwich at Medway, Chatham, ME7 4TB, UK
| | - Felipe Ossa
- Centre for Cardiovascular Medicine and Device Innovation, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - John C Edwards
- Department of Internal Medicine, Saint Louis University, St. Louis, MO, USA
| | - Vahitha Abdul-Salam
- Centre for Cardiovascular Medicine and Device Innovation, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | | |
Collapse
|
7
|
Discovery of archaeal fusexins homologous to eukaryotic HAP2/GCS1 gamete fusion proteins. Nat Commun 2022; 13:3880. [PMID: 35794124 PMCID: PMC9259645 DOI: 10.1038/s41467-022-31564-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 06/22/2022] [Indexed: 12/26/2022] Open
Abstract
AbstractSexual reproduction consists of genome reduction by meiosis and subsequent gamete fusion. The presence of genes homologous to eukaryotic meiotic genes in archaea and bacteria suggests that DNA repair mechanisms evolved towards meiotic recombination. However, fusogenic proteins resembling those found in gamete fusion in eukaryotes have so far not been found in prokaryotes. Here, we identify archaeal proteins that are homologs of fusexins, a superfamily of fusogens that mediate eukaryotic gamete and somatic cell fusion, as well as virus entry. The crystal structure of a trimeric archaeal fusexin (Fusexin1 or Fsx1) reveals an archetypical fusexin architecture with unique features such as a six-helix bundle and an additional globular domain. Ectopically expressed Fusexin1 can fuse mammalian cells, and this process involves the additional globular domain and a conserved fusion loop. Furthermore, archaeal fusexin genes are found within integrated mobile elements, suggesting potential roles in cell-cell fusion and gene exchange in archaea, as well as different scenarios for the evolutionary history of fusexins.
Collapse
|
8
|
Basso LGM, Zeraik AE, Felizatti AP, Costa-Filho AJ. Membranotropic and biological activities of the membrane fusion peptides from SARS-CoV spike glycoprotein: The importance of the complete internal fusion peptide domain. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2021; 1863:183697. [PMID: 34274319 PMCID: PMC8280623 DOI: 10.1016/j.bbamem.2021.183697] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/05/2021] [Accepted: 07/10/2021] [Indexed: 11/28/2022]
Abstract
Fusion peptides (FP) are prominent hydrophobic segments of viral fusion proteins that play critical roles in viral entry. FPs interact with and insert into the host lipid membranes, triggering conformational changes in the viral protein that leads to the viral-cell fusion. Multiple membrane-active domains from the severe acute respiratory syndrome (SARS) coronavirus (CoV) spike protein have been reported to act as the functional fusion peptide such as the peptide sequence located between the S1/S2 and S2' cleavage sites (FP1), the S2'-adjacent fusion peptide domain (FP2), and the internal FP sequence (cIFP). Using a combined biophysical approach, we demonstrated that the α-helical coiled-coil-forming internal cIFP displayed the highest membrane fusion and permeabilizing activities along with membrane ordering effect in phosphatidylcholine (PC)/phosphatidylglycerol (PG) unilamellar vesicles compared to the other two N-proximal fusion peptide counterparts. While the FP1 sequence displayed intermediate membranotropic activities, the well-conserved FP2 peptide was substantially less effective in promoting fusion, leakage, and membrane ordering in PC/PG model membranes. Furthermore, Ca2+ did not enhance the FP2-induced lipid mixing activity in PC/phosphatidylserine/cholesterol lipid membranes, despite its strong erythrocyte membrane perturbation. Nonetheless, we found that the three putative SARS-CoV membrane-active fusion peptide sequences here studied altered the physical properties of model and erythrocyte membranes to different extents. The importance of the distinct membranotropic and biological activities of all SARS-CoV fusion peptide domains and the pronounced effect of the internal fusion peptide sequence to the whole spike-mediated membrane fusion process are discussed.
Collapse
Affiliation(s)
- Luis Guilherme Mansor Basso
- Laboratório de Ciências Físicas, Centro de Ciência e Tecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego, 2000, 28013-602 Campos dos Goytacazes, RJ, Brazil; Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes, 3900, 14040-901 Ribeirão Preto, SP, Brazil.
| | - Ana Eliza Zeraik
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego, 2000, 28013-602 Campos dos Goytacazes, RJ, Brazil; Grupo de Biofísica e Biologia Estrutural "Sérgio Mascarenhas", Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador São-carlense, 400, Centro, São Carlos, SP, Brazil
| | - Ana Paula Felizatti
- Laboratório de Produtos Naturais, Departamento de Química, Centro de Ciências Exatas e de Tecnologia, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, Monjolinho, 13565905, São Carlos, SP, Brazil; Grupo de Biofísica e Biologia Estrutural "Sérgio Mascarenhas", Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador São-carlense, 400, Centro, São Carlos, SP, Brazil
| | - Antonio José Costa-Filho
- Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes, 3900, 14040-901 Ribeirão Preto, SP, Brazil.
| |
Collapse
|
9
|
Abstract
Rubella virus (RUBV), a rubivirus, is an airborne human pathogen that generally causes mild measles-like symptoms in children or adults. However, RUBV infection of pregnant women can result in miscarriage or congenital rubella syndrome (CRS), a collection of long-term birth defects including incomplete organ development and mental retardation. Worldwide vaccination campaigns have significantly reduced the number of RUBV infections, but RUBV continues to be a problem in countries with low vaccination coverage. Further, the recent discovery of pathogenic rubiviruses in other mammals emphasizes the spillover potential of rubella-related viruses to humans. In the last decade, our understanding of RUBV has been significantly increased by virological, biochemical, and structural studies, providing a platform to begin understanding the life cycle of RUBV at the molecular level. This review concentrates on recent work on RUBV, focusing on the virion, its structural components, and its entry, fusion, and assembly mechanisms. Important features of RUBV are compared with those of viruses from other families. We also use comparative genomics, manual curation, and protein homology modeling to highlight distinct features of RUBV that are evolutionarily conserved in the non-human rubiviruses. Since rubella-like viruses may potentially have higher pathogenicity and transmissibility to humans, we also propose a framework for utilizing RUBV as a model to study its more pathogenic cousins.
Collapse
|
10
|
Islam MT, Quispe C, Martorell M, Docea AO, Salehi B, Calina D, Reiner Ž, Sharifi-Rad J. Dietary supplements, vitamins and minerals as potential interventions against viruses: Perspectives for COVID-19. INT J VITAM NUTR RES 2021; 92:49-66. [DOI: 10.1024/0300-9831/a000694] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Abstract. The novel coronavirus (SARS-CoV-2) causing COVID-19 disease pandemic has infected millions of people and caused more than thousands of deaths in many countries across the world. The number of infected cases is increasing day by day. Unfortunately, we do not have a vaccine and specific treatment for it. Along with the protective measures, respiratory and/or circulatory supports and some antiviral and retroviral drugs have been used against SARS-CoV-2, but there are no more extensive studies proving their efficacy. In this study, the latest publications in the field have been reviewed, focusing on the modulatory effects on the immunity of some natural antiviral dietary supplements, vitamins and minerals. Findings suggest that several dietary supplements, including black seeds, garlic, ginger, cranberry, orange, omega-3 and -6 polyunsaturated fatty acids, vitamins (e.g., A, B vitamins, C, D, E), and minerals (e.g., Cu, Fe, Mg, Mn, Na, Se, Zn) have anti-viral effects. Many of them act against various species of respiratory viruses, including severe acute respiratory syndrome-related coronaviruses. Therefore, dietary supplements, including vitamins and minerals, probiotics as well as individual nutritional behaviour can be used as adjuvant therapy together with antiviral medicines in the management of COVID-19 disease.
Collapse
Affiliation(s)
- Muhammad Torequl Islam
- Department of Pharmacy, Life Science Faculty, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Bangladesh
| | - Cristina Quispe
- Facultad de Ciencias de la Salud, Universidad Arturo Prat, Chile
| | - Miquel Martorell
- Department of Nutrition and Dietetics, Faculty of Pharmacy, and Centre for Healthy Living, University of Concepción, Concepción, Chile
- Universidad de Concepción, Unidad de Desarrollo Tecnológico (UDT), Concepción, Chile
| | - Anca Oana Docea
- Department of Toxicology, University of Medicine and Pharmacy of Craiova, Romania
| | - Bahare Salehi
- Medical Ethics and Law Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Daniela Calina
- Department of Clinical Pharmacy, University of Medicine and Pharmacy of Craiova, Romania
| | - Željko Reiner
- Department of Internal Medicine, University Hospital Centre Zagreb, School of Medicine, University of Zagreb, Croatia
| | - Javad Sharifi-Rad
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Facultad de Medicina, Universidad del Azuay, Cuenca, Ecuador
| |
Collapse
|
11
|
ACE2: from protection of liver disease to propagation of COVID-19. Clin Sci (Lond) 2020; 134:3137-3158. [PMID: 33284956 DOI: 10.1042/cs20201268] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/19/2020] [Accepted: 11/23/2020] [Indexed: 01/08/2023]
Abstract
Twenty years ago, the discovery of angiotensin-converting enzyme 2 (ACE2) was an important breakthrough dramatically enhancing our understanding of the renin-angiotensin system (RAS). The classical RAS is driven by its key enzyme ACE and is pivotal in the regulation of blood pressure and fluid homeostasis. More recently, it has been recognised that the protective RAS regulated by ACE2 counterbalances many of the deleterious effects of the classical RAS. Studies in murine models demonstrated that manipulating the protective RAS can dramatically alter many diseases including liver disease. Liver-specific overexpression of ACE2 in mice with liver fibrosis has proved to be highly effective in antagonising liver injury and fibrosis progression. Importantly, despite its highly protective role in disease pathogenesis, ACE2 is hijacked by SARS-CoV-2 as a cellular receptor to gain entry to alveolar epithelial cells, causing COVID-19, a severe respiratory disease in humans. COVID-19 is frequently life-threatening especially in elderly or people with other medical conditions. As an unprecedented number of COVID-19 patients have been affected globally, there is an urgent need to discover novel therapeutics targeting the interaction between the SARS-CoV-2 spike protein and ACE2. Understanding the role of ACE2 in physiology, pathobiology and as a cellular receptor for SARS-CoV-2 infection provides insight into potential new therapeutic strategies aiming to prevent SARS-CoV-2 infection related tissue injury. This review outlines the role of the RAS with a strong focus on ACE2-driven protective RAS in liver disease and provides therapeutic approaches to develop strategies to prevent SARS-CoV-2 infection in humans.
Collapse
|
12
|
Tang T, Bidon M, Jaimes JA, Whittaker GR, Daniel S. Coronavirus membrane fusion mechanism offers a potential target for antiviral development. Antiviral Res 2020. [PMID: 32272173 DOI: 10.1016/j.antiviral.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic has focused attention on the need to develop effective therapies against the causative agent, SARS-CoV-2, and also against other pathogenic coronaviruses (CoV) that have emerged in the past or might appear in future. Researchers are therefore focusing on steps in the CoV replication cycle that may be vulnerable to inhibition by broad-spectrum or specific antiviral agents. The conserved nature of the fusion domain and mechanism across the CoV family make it a valuable target to elucidate and develop pan-CoV therapeutics. In this article, we review the role of the CoV spike protein in mediating fusion of the viral and host cell membranes, summarizing the results of research on SARS-CoV, MERS-CoV, and recent peer-reviewed studies of SARS-CoV-2, and suggest that the fusion mechanism be investigated as a potential antiviral target. We also provide a supplemental file containing background information on the biology, epidemiology, and clinical features of all human-infecting coronaviruses, along with a phylogenetic tree of these coronaviruses.
Collapse
Affiliation(s)
- Tiffany Tang
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Miya Bidon
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Javier A Jaimes
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, 14853, USA
| | - Gary R Whittaker
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, 14853, USA
| | - Susan Daniel
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA.
| |
Collapse
|
13
|
Tang T, Bidon M, Jaimes JA, Whittaker GR, Daniel S. Coronavirus membrane fusion mechanism offers a potential target for antiviral development. Antiviral Res 2020; 178:104792. [PMID: 32272173 PMCID: PMC7194977 DOI: 10.1016/j.antiviral.2020.104792] [Citation(s) in RCA: 515] [Impact Index Per Article: 128.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 04/05/2020] [Accepted: 04/05/2020] [Indexed: 12/14/2022]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic has focused attention on the need to develop effective therapies against the causative agent, SARS-CoV-2, and also against other pathogenic coronaviruses (CoV) that have emerged in the past or might appear in future. Researchers are therefore focusing on steps in the CoV replication cycle that may be vulnerable to inhibition by broad-spectrum or specific antiviral agents. The conserved nature of the fusion domain and mechanism across the CoV family make it a valuable target to elucidate and develop pan-CoV therapeutics. In this article, we review the role of the CoV spike protein in mediating fusion of the viral and host cell membranes, summarizing the results of research on SARS-CoV, MERS-CoV, and recent peer-reviewed studies of SARS-CoV-2, and suggest that the fusion mechanism be investigated as a potential antiviral target. We also provide a supplemental file containing background information on the biology, epidemiology, and clinical features of all human-infecting coronaviruses, along with a phylogenetic tree of these coronaviruses.
Collapse
Affiliation(s)
- Tiffany Tang
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Miya Bidon
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Javier A Jaimes
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, 14853, USA
| | - Gary R Whittaker
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, 14853, USA
| | - Susan Daniel
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA.
| |
Collapse
|
14
|
Heat Shock Protein 90 Ensures the Integrity of Rubella Virus p150 Protein and Supports Viral Replication. J Virol 2019; 93:JVI.01142-19. [PMID: 31484751 DOI: 10.1128/jvi.01142-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 08/21/2019] [Indexed: 12/18/2022] Open
Abstract
Two viral nonstructural proteins, p150 and p90, are expressed in rubella virus (RUBV)-infected cells and mediate viral genome replication, presumably using various host machineries. Molecular chaperones are critical host factors for the maintenance of cellular proteostasis, and certain viral proteins use this chaperone system. The RUBV p150 and p90 proteins are generated from a precursor polyprotein, p200, via processing by the protease activity of its p150 region. This processing is essential for RUBV genome replication. Here we show that heat shock protein 90 (HSP90), a molecular chaperone, is an important host factor for RUBV genome replication. The treatment of RUBV-infected cells with the HSP90 inhibitors 17-allylamino-17-desmethoxygeldanamycin (17-AAG) and ganetespib suppressed RUBV genome replication. HSP90α physically interacted with p150, but not p90. Further analyses into the mechanism of action of the HSP90 inhibitors revealed that HSP90 activity contributes to p150 functional integrity and promotes p200 processing. Collectively, our data demonstrate that RUBV p150 is a client of the HSP90 molecular chaperone and that HSP90 functions as a key host factor for RUBV replication.IMPORTANCE Accumulating evidence indicates that RNA viruses use numerous host factors during replication of their genomes. However, the host factors involved in rubella virus (RUBV) genome replication are largely unknown. In this study, we demonstrate that the HSP90 molecular chaperone is needed for the efficient replication of the RUBV genome. Further, we reveal that HSP90 interacts with RUBV nonstructural protein p150 and its precursor polyprotein, p200. HSP90 contributes to the stability of p150 and the processing of p200 via its protease domain in the p150 region. We conclude that the cellular molecular chaperone HSP90 is a key host factor for functional maturation of nonstructural proteins for RUBV genome replication. These findings provide novel insight into this host-virus interaction.
Collapse
|
15
|
Punch EK, Hover S, Blest HTW, Fuller J, Hewson R, Fontana J, Mankouri J, Barr JN. Potassium is a trigger for conformational change in the fusion spike of an enveloped RNA virus. J Biol Chem 2018; 293:9937-9944. [PMID: 29678879 PMCID: PMC6028977 DOI: 10.1074/jbc.ra118.002494] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/11/2018] [Indexed: 01/23/2023] Open
Abstract
Many enveloped viruses enter cells through the endocytic network, from which they must subsequently escape through fusion of viral and endosomal membranes. This membrane fusion is mediated by virus-encoded spikes that respond to the dynamic endosomal environment, which triggers conformational changes in the spikes that initiate the fusion process. Several fusion triggers have been identified and include pH, membrane composition, and endosome-resident proteins, and these cues dictate when and where viral fusion occurs. We recently reported that infection with an enveloped bunyavirus requires elevated potassium ion concentrations [K+], controlled by cellular K+ channels, that are encountered during viral transit through maturing endosomes. Here we reveal the molecular basis for the K+ requirement of bunyaviruses through the first direct visualization of a member of the Nairoviridae family, namely Hazara virus (HAZV), using cryo-EM. Using cryo-electron tomography, we observed HAZV spike glycoproteins within infectious HAZV particles exposed to both high and low [K+], which showed that exposure to K+ alone results in dramatic changes to the ultrastructural architecture of the virion surface. In low [K+], the spikes adopted a compact conformation arranged in locally ordered arrays, whereas, following exposure to high [K+], the spikes became extended, and spike–membrane interactions were observed. Viruses exposed to high [K+] also displayed enhanced infectivity, thus identifying K+ as a newly defined trigger that helps promote viral infection. Finally, we confirmed that K+ channel blockers are inhibitory to HAZV infection, highlighting the potential of K+ channels as anti-bunyavirus targets.
Collapse
Affiliation(s)
- Emma K Punch
- From the School of Molecular and Cellular Biology and
| | | | | | - Jack Fuller
- From the School of Molecular and Cellular Biology and.,the National Infection Service, Public Health England, Porton Down, Salisbury SP4 0JG, United Kingdom
| | - Roger Hewson
- the National Infection Service, Public Health England, Porton Down, Salisbury SP4 0JG, United Kingdom
| | - Juan Fontana
- From the School of Molecular and Cellular Biology and.,Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom and
| | - Jamel Mankouri
- From the School of Molecular and Cellular Biology and.,Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom and
| | - John N Barr
- From the School of Molecular and Cellular Biology and .,Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom and
| |
Collapse
|
16
|
Millet JK, Whittaker GR. Physiological and molecular triggers for SARS-CoV membrane fusion and entry into host cells. Virology 2017; 517:3-8. [PMID: 29275820 PMCID: PMC7112017 DOI: 10.1016/j.virol.2017.12.015] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/13/2017] [Accepted: 12/15/2017] [Indexed: 11/17/2022]
Abstract
During viral entry, enveloped viruses require the fusion of their lipid envelope with host cell membranes. For coronaviruses, this critical step is governed by the virally-encoded spike (S) protein, a class I viral fusion protein that has several unique features. Coronavirus entry is unusual in that it is often biphasic in nature, and can occur at or near the cell surface or in late endosomes. Recent advances in structural, biochemical and molecular biology of the coronavirus S protein has shed light on the intricacies of coronavirus entry, in particular the molecular triggers of coronavirus S-mediated membrane fusion. Furthermore, characterization of the coronavirus fusion peptide (FP), the segment of the fusion protein that inserts to a target lipid bilayer during membrane fusion, has revealed its particular attributes which imparts some of the unusual properties of the S protein, such as Ca2+-dependency. These unusual characteristics can explain at least in part the biphasic nature of coronavirus entry. In this review, using severe acute respiratory syndrome coronavirus (SARS-CoV) as model virus, we give an overview of advances in research on the coronavirus fusion peptide with an emphasis on its role and properties within the biological context of host cell entry.
Collapse
Affiliation(s)
- Jean Kaoru Millet
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, United States
| | - Gary R Whittaker
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, United States.
| |
Collapse
|
17
|
Both Sphingomyelin and Cholesterol in the Host Cell Membrane Are Essential for Rubella Virus Entry. J Virol 2017; 92:JVI.01130-17. [PMID: 29070689 DOI: 10.1128/jvi.01130-17] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 10/17/2017] [Indexed: 11/20/2022] Open
Abstract
Rubella virus (RuV) causes a systemic infection, and transplacental fetal infection causes congenital rubella syndrome. In this study, we showed that treatment of cells with sphingomyelinase inhibited RuV infection. Assays using inhibitors of serine palmitoyl transferase and ceramide transport protein demonstrated the contribution of sphingomyelin (SM) to RuV infection. Compelling evidence for direct binding of RuV to lipid membranes at neutral pH was obtained using liposome coflotation assays. The absence of either SM or cholesterol (Chol) abrogated the RuV-liposome interaction. SM and Chol (SM/Chol) were also critical for RuV binding to erythrocytes and lymphoid cells. Removal of Ca2+ from the assay buffer or mutation of RuV envelope E1 protein Ca2+-binding sites abrogated RuV binding to liposomes, erythrocytes, and lymphoid cells. However, RuV bound to various nonlymphoid adherent cell lines independently of extracellular Ca2+ or SM/Chol. Even in these adherent cell lines, both the E1 protein Ca2+-binding sites and cellular SM/Chol were essential for the early stage of RuV infection, possibly affecting envelope-membrane fusion in acidic compartments. Myelin oligodendrocyte glycoprotein (MOG) has recently been identified as a cellular receptor for RuV. However, RuV bound to MOG-negative cells in a Ca2+-independent manner. Collectively, our data demonstrate that RuV has two distinct binding mechanisms: one is Ca2+ dependent and the other is Ca2+ independent. Ca2+-dependent binding observed in lymphoid cells occurs by the direct interaction between E1 protein fusion loops and SM/Chol-enriched membranes. Clarification of the mechanism of Ca2+-independent RuV binding is an important next step in understanding the pathology of RuV infection.IMPORTANCE Rubella has a significant impact on public health as infection during early pregnancy can result in babies being born with congenital rubella syndrome. Even though effective rubella vaccines are available, rubella outbreaks still occur in many countries. We studied the entry mechanism of rubella virus (RuV) and found that RuV binds directly to the host plasma membrane in the presence of Ca2+ at neutral pH. This Ca2+-dependent binding is specifically directed to membranes enriched in sphingomyelin and cholesterol and is critical for RuV infection. Importantly, RuV also binds to many cell lines in a Ca2+-independent manner. An unidentified RuV receptor(s) is involved in this Ca2+-independent binding. We believe that the data presented here may aid the development of the first anti-RuV drug.
Collapse
|
18
|
Analysis of VSV pseudotype virus infection mediated by rubella virus envelope proteins. Sci Rep 2017; 7:11607. [PMID: 28912595 PMCID: PMC5599607 DOI: 10.1038/s41598-017-10865-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 08/16/2017] [Indexed: 01/20/2023] Open
Abstract
Rubella virus (RV) generally causes a systemic infection in humans. Viral cell tropism is a key determinant of viral pathogenesis, but the tropism of RV is currently poorly understood. We analyzed various human cell lines and determined that RV only establishes an infection efficiently in particular non-immune cell lines. To establish an infection the host cells must be susceptible and permissible. To assess the susceptibility of individual cell lines, we generated a pseudotype vesicular stomatitis virus bearing RV envelope proteins (VSV-RV/CE2E1). VSV-RV/CE2E1 entered cells in an RV envelope protein-dependent manner, and thus the infection was neutralized completely by an RV-specific antibody. The infection was Ca2+-dependent and inhibited by endosomal acidification inhibitors, further confirming the dependency on RV envelope proteins for the VSV-RV/CE2E1 infection. Human non-immune cell lines were mostly susceptible to VSV-RV/CE2E1, while immune cell lines were much less susceptible than non-immune cell lines. However, susceptibility of immune cells to VSV-RV/CE2E1 was increased upon stimulation of these cells. Our data therefore suggest that immune cells are generally less susceptible to RV infection than non-immune cells, but the susceptibility of immune cells is enhanced upon stimulation.
Collapse
|
19
|
Desai TM, Marin M, Mason C, Melikyan GB. pH regulation in early endosomes and interferon-inducible transmembrane proteins control avian retrovirus fusion. J Biol Chem 2017; 292:7817-7827. [PMID: 28341742 DOI: 10.1074/jbc.m117.783878] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/22/2017] [Indexed: 01/09/2023] Open
Abstract
Enveloped viruses infect host cells by fusing their membranes with those of the host cell, a process mediated by viral glycoproteins upon binding to cognate host receptors or entering into acidic intracellular compartments. Whereas the effect of receptor density on viral infection has been well studied, the role of cell type-specific factors/processes, such as pH regulation, has not been characterized in sufficient detail. Here, we examined the effects of cell-extrinsic factors (buffer environment) and cell-intrinsic factors (interferon-inducible transmembrane proteins, IFITMs), on the pH regulation in early endosomes and on the efficiency of acid-dependent fusion of the avian sarcoma and leukosis virus (ASLV), with endosomes. First, we found that a modest elevation of external pH can raise the pH in early endosomes in a cell type-dependent manner and thereby delay the acid-induced fusion of endocytosed ASLV. Second, we observed a cell type-dependent delay between the low pH-dependent and temperature-dependent steps of viral fusion, consistent with the delayed enlargement of the fusion pore. Third, ectopic expression of IFITMs, known to potently block influenza virus fusion with late compartments, was found to only partially inhibit ASLV fusion with early endosomes. Interestingly, IFITM expression promoted virus uptake and the acidification of endosomal compartments, resulting in an accelerated fusion rate when driven by the glycosylphosphatidylinositol-anchored, but not by the transmembrane isoform of the ASLV receptor. Collectively, these results highlight the role of cell-extrinsic and cell-intrinsic factors in regulating the efficiency and kinetics of virus entry and fusion with target cells.
Collapse
Affiliation(s)
- Tanay M Desai
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and
| | - Mariana Marin
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and
| | - Caleb Mason
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and
| | - Gregory B Melikyan
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and .,the Children's Healthcare of Atlanta, Atlanta, Georgia 300322
| |
Collapse
|