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Cedillo-Barrón L, García-Cordero J, Visoso-Carvajal G, León-Juárez M. Viroporins Manipulate Cellular Powerhouses and Modulate Innate Immunity. Viruses 2024; 16:345. [PMID: 38543711 PMCID: PMC10974846 DOI: 10.3390/v16030345] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/02/2024] [Accepted: 02/02/2024] [Indexed: 05/23/2024] Open
Abstract
Viruses have a wide repertoire of molecular strategies that focus on their replication or the facilitation of different stages of the viral cycle. One of these strategies is mediated by the activity of viroporins, which are multifunctional viral proteins that, upon oligomerization, exhibit ion channel properties with mild ion selectivity. Viroporins facilitate multiple processes, such as the regulation of immune response and inflammasome activation through the induction of pore formation in various cell organelle membranes to facilitate the escape of ions and the alteration of intracellular homeostasis. Viroporins target diverse membranes (such as the cellular membrane), endoplasmic reticulum, and mitochondria. Cumulative data regarding the importance of mitochondria function in multiple processes, such as cellular metabolism, energy production, calcium homeostasis, apoptosis, and mitophagy, have been reported. The direct or indirect interaction of viroporins with mitochondria and how this interaction affects the functioning of mitochondrial cells in the innate immunity of host cells against viruses remains unclear. A better understanding of the viroporin-mitochondria interactions will provide insights into their role in affecting host immune signaling through the mitochondria. Thus, in this review, we mainly focus on descriptions of viroporins and studies that have provided insights into the role of viroporins in hijacked mitochondria.
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Affiliation(s)
- Leticia Cedillo-Barrón
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV-IPN) Av., IPN # 2508 Col., San Pedro Zacatenco, Mexico City 07360, Mexico; (J.G.-C.); (G.V.-C.)
| | - Julio García-Cordero
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV-IPN) Av., IPN # 2508 Col., San Pedro Zacatenco, Mexico City 07360, Mexico; (J.G.-C.); (G.V.-C.)
| | - Giovani Visoso-Carvajal
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV-IPN) Av., IPN # 2508 Col., San Pedro Zacatenco, Mexico City 07360, Mexico; (J.G.-C.); (G.V.-C.)
- Escuela Superior de Medicina, Instituto Politécnico Nacional, Salvador Díaz Mirón esq, Plan de San Luis S/N, Miguel Hidalgo, Casco de Santo Tomas, Mexico City 11340, Mexico
| | - Moisés León-Juárez
- Instituto Nacional de Perinatología Isidro Espinosa de los Reyes, Mexico City 11000, Mexico;
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2
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King KE, Ghosh P, Wozniak AL. TRIM25 dictates selective miRNA loading into extracellular vesicles during inflammation. Sci Rep 2023; 13:22952. [PMID: 38135735 PMCID: PMC10746700 DOI: 10.1038/s41598-023-50336-5] [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: 06/02/2023] [Accepted: 12/19/2023] [Indexed: 12/24/2023] Open
Abstract
Extracellular vesicles (EVs) such as exosomes are loaded with specific biomolecules in order to perform cell-to-cell communication. Understanding the mechanism of selective cargo loading is important to better understand the physiological and pathological function of EVs. Here we describe a novel target of the E3 ligase TRIM25 and show that inflammation-mediated EV loading of the RNA binding protein FMR1 and its associated microRNA, miR-155, is promoted by TRIM25-mediated K63-ubiquitination of FMR1. This ubiquitination promotes an interaction between FMR1 and the EV loading machinery via the cleavage of the trafficking adaptor protein RILP. These interactions are lost when TRIM25 is knocked down. Loss of TRIM25 also prevents the loading of both FMR1 and miR-155. These findings suggest that inflammation-mediated loading of FMR1 and its associated microRNAs into the EV are dependent on K63-ubiquitination by TRIM25 and provide novel insights and tools to manipulate EV biogenesis for therapeutic benefit.
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Affiliation(s)
- Kayla E King
- Department of Internal Medicine, University of Kansas Medical Center, Mailstop 1018, Kansas City, KS, 66160, USA
- Liver Center, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Priyanka Ghosh
- Department of Internal Medicine, University of Kansas Medical Center, Mailstop 1018, Kansas City, KS, 66160, USA
- Liver Center, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Ann L Wozniak
- Department of Internal Medicine, University of Kansas Medical Center, Mailstop 1018, Kansas City, KS, 66160, USA.
- Liver Center, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
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3
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Granier C, Toesca J, Mialon C, Ritter M, Freitas N, Boson B, Pécheur EI, Cosset FL, Denolly S. Low-density hepatitis C virus infectious particles are protected from oxidation by secreted cellular proteins. mBio 2023; 14:e0154923. [PMID: 37671888 PMCID: PMC10653866 DOI: 10.1128/mbio.01549-23] [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: 06/17/2023] [Accepted: 07/04/2023] [Indexed: 09/07/2023] Open
Abstract
IMPORTANCE Assessments of viral stability on surfaces or in body fluids under different environmental conditions and/or temperatures are often performed, as they are key to understanding the routes and parameters of viral transmission and to providing clues on the epidemiology of infections. However, for most viruses, the mechanisms of inactivation vs stability of viral particles remain poorly defined. Although they are structurally diverse, with different compositions, sizes, and shapes, enveloped viruses are generally less stable than non-enveloped viruses, pointing out the role of envelopes themselves in virus lability. In this report, we investigated the properties of hepatitis C virus (HCV) particles with regards to their stability. We found that, compared to alternative enveloped viruses such as Dengue virus (DENV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), hepatitis delta virus (HDV), and Crimean-Congo hemorrhagic fever virus (CCHFV) that infect the liver, HCV particles are intrinsically labile. We determined the mechanisms that drastically alter their specific infectivity through oxidation of their lipids, and we highlighted that they are protected from lipid oxidation by secreted cellular proteins, which can protect their membrane fusion capacity and overall infectivity.
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Affiliation(s)
- Christelle Granier
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
| | - Johan Toesca
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
| | - Chloé Mialon
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
| | - Maureen Ritter
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
| | - Natalia Freitas
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
| | - Bertrand Boson
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
| | - Eve-Isabelle Pécheur
- Centre Léon Bérard, Centre de Recherche en Cancérologie de Lyon, CNRS 5286, Inserm U1052, Université Claude Bernard Lyon 1, Lyon, France
| | - François-Loïc Cosset
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
| | - Solène Denolly
- CIRI – Centre International de Recherche en Infectiologie, Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308 ENS de Lyon, Lyon, France
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
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ARIFFIANTO ADI, DENG LIN, HARADA SAKI, LIANG YUJIAO, MATSUI CHIEKO, ABE TAKAYUKI, SHOJI IKUO. Transcription Factor JunB Suppresses Hepatitis C Virus Replication. THE KOBE JOURNAL OF MEDICAL SCIENCES 2023; 69:E86-E95. [PMID: 37661632 PMCID: PMC10695097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 06/28/2023] [Indexed: 09/05/2023]
Abstract
We previously reported that hepatitis C virus (HCV) infection activates the reactive oxygen species (ROS)/c-Jun N-terminal kinase (JNK) signaling pathway. Activation of JNK contributes to the development of liver diseases, including metabolic disorders, steatosis, liver cirrhosis and hepatocellular carcinoma. JNK is known to have numerous target genes, including JunB, a member of activator protein-1 transcription factor family. However, the roles of JunB in the HCV life cycle and HCV-associated pathogenesis remain unclear. To clarify a physiological role of JunB in HCV infection, we investigated the phosphorylation of JunB in HCV J6/JFH1-infected Huh-7.5 cells. Immunoblot analysis revealed that HCV-induced ROS/JNK activation promoted phosphorylation of JunB. The small interfering RNA (siRNA) knockdown of JunB significantly increased the amount of intracellular HCV RNA as well as the intracellular and extracellular HCV infectivity titers. Conversely, overexpression of JunB significantly reduced the amount of intracellular HCV RNA and the intracellular and extracellular HCV infectivity titers. These results suggest that JunB plays a role in inhibiting HCV propagation. Additionally, HCV-mediated JunB activation promoted hepcidin promoter activity and hepcidin mRNA levels, a key factor in modulating iron homeostasis, suggesting that JunB is involved in HCV-induced transcriptional upregulation of hepcidin. Taken together, we propose that the HCV-induced ROS/JNK/JunB signaling pathway plays roles in inhibiting HCV replication and contributing to HCV-mediated iron metabolism disorder.
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Affiliation(s)
- ADI ARIFFIANTO
- Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan
| | - LIN DENG
- Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan
| | - SAKI HARADA
- Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan
| | - YUJIAO LIANG
- Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan
| | - CHIEKO MATSUI
- Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan
| | - TAKAYUKI ABE
- Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan
| | - IKUO SHOJI
- Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan
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Campbell O, Monje-Galvan V. Protein-driven membrane remodeling: Molecular perspectives from Flaviviridae infections. Biophys J 2023; 122:1890-1899. [PMID: 36369756 PMCID: PMC10257083 DOI: 10.1016/j.bpj.2022.11.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/23/2022] [Accepted: 11/07/2022] [Indexed: 11/13/2022] Open
Abstract
The mammalian cell membrane consists of thousands of different lipid species, and this variety is critical for biological function. Alterations to this balance can be dangerous as they can lead to permanent disruption of lipid metabolism, a hallmark in several viral diseases. The Flaviviridae family is made up of positive single-stranded RNA viruses that assemble at or near the location of lipid droplet formation in the endoplasmic reticulum. These viruses are known to interfere with lipid metabolism during the onset of liver disease, albeit to different extents. Pathogenesis of these infections involves specific protein-lipid interactions that alter lipid sorting and metabolism to sustain propagation of the viral infection. Recent experimental studies identify a correlation between viral proteins and lipid content or location in the cell, but these do not assess membrane-embedded interactions. Molecular modeling, specifically molecular dynamics simulations, can provide molecular-level spatial and temporal resolution for characterization of biomolecular interactions. This review focuses on recent advancements and current knowledge gaps in the molecular mechanisms of lipid-mediated liver disease preceded by viral infection. We discuss three viruses from the Flaviviridae family: dengue, zika, and hepatitis C, with a particular focus on lipid interactions with their respective ion channels, known as viroporins.
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Affiliation(s)
- Oluwatoyin Campbell
- Department of Chemical and Biological Engineering, University at Buffalo, Buffalo, New York
| | - Viviana Monje-Galvan
- Department of Chemical and Biological Engineering, University at Buffalo, Buffalo, New York.
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6
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Benazraf A, Arkin IT. Exhaustive mutational analysis of severe acute respiratory syndrome coronavirus 2 ORF3a: An essential component in the pathogen's infectivity cycle. Protein Sci 2023; 32:e4528. [PMID: 36468608 PMCID: PMC9795539 DOI: 10.1002/pro.4528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/15/2022] [Accepted: 11/21/2022] [Indexed: 12/07/2022]
Abstract
Detailed knowledge of a protein's key residues may assist in understanding its function and designing inhibitors against it. Consequently, such knowledge of one of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)'s proteins is advantageous since the virus is the etiological agent behind one of the biggest health crises of recent times. To that end, we constructed an exhaustive library of bacteria differing from each other by the mutated version of the virus's ORF3a viroporin they harbor. Since the protein is harmful to bacterial growth due to its channel activity, genetic selection followed by deep sequencing could readily identify mutations that abolish the protein's function. Our results have yielded numerous mutations dispersed throughout the sequence that counteract ORF3a's ability to slow bacterial growth. Comparing these data with the conservation pattern of ORF3a within the coronavirinae provided interesting insights: Deleterious mutations obtained in our study corresponded to conserved residues in the protein. However, despite the comprehensive nature of our mutagenesis coverage (108 average mutations per site), we could not reveal all of the protein's conserved residues. Therefore, it is tempting to speculate that our study unearthed positions in the protein pertinent to channel activity, while other conserved residues may correspond to different functionalities of ORF3a. In conclusion, our study provides important information on a key component of SARS-CoV-2 and establishes a procedure to analyze other viroporins comprehensively.
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Affiliation(s)
- Amit Benazraf
- Department of Biological ChemistryThe Alexander Silberman Institute of Life Sciences, The Hebrew University of JerusalemJerusalemIsrael
| | - Isaiah T. Arkin
- Department of Biological ChemistryThe Alexander Silberman Institute of Life Sciences, The Hebrew University of JerusalemJerusalemIsrael
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7
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Vargas-Zapata V, Geiger KM, Tran D, Ma J, Mao X, Puschnik AS, Coscoy L. SARS-CoV-2 Envelope-mediated Golgi pH dysregulation interferes with ERAAP retention in cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022:2022.11.29.518257. [PMID: 36482965 PMCID: PMC9727756 DOI: 10.1101/2022.11.29.518257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Endoplasmic reticulum (ER) aminopeptidase associated with antigen processing (ERAAP) trims peptide precursors in the ER for presentation by major histocompatibility (MHC)-I molecules to surveying CD8+ T-cells. This function allows ERAAP to regulate the nature and quality of the peptide repertoire and, accordingly, the resulting immune responses. We recently showed that infection with murine cytomegalovirus leads to a dramatic loss of ERAAP levels in infected cells. In mice, this loss is associated with the activation of QFL T-cells, a subset of T-cells that monitor ERAAP integrity and eliminate cells experiencing ERAAP dysfunction. In this study, we aimed to identify host factors that regulate ERAAP expression level and determine whether these could be manipulated during viral infections. We performed a CRISPR knockout screen and identified ERp44 as a factor promoting ERAAP retention in the ER. ERp44's interaction with ERAAP is dependent on the pH gradient between the ER and Golgi. We hypothesized that viruses that disrupt the pH of the secretory pathway interfere with ERAAP retention. Here, we demonstrate that expression of the Envelope (E) protein from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) leads to Golgi pH neutralization and consequently decrease of ERAAP intracellular levels. Furthermore, SARS-CoV-2-induced ERAAP loss correlates with its release into the extracellular environment. ERAAP's reliance on ERp44 and a functioning ER/Golgi pH gradient for proper localization and function led us to propose that ERAAP serves as a sensor of disturbances in the secretory pathway during infection and disease.
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Affiliation(s)
- Valerie Vargas-Zapata
- Division of Immunology and Molecular Medicine, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Kristina M Geiger
- Division of Immunology and Molecular Medicine, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, 94720, USA
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Dan Tran
- Division of Immunology and Molecular Medicine, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Jessica Ma
- Division of Microbial Biology, Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Xiaowen Mao
- Division of Immunology and Molecular Medicine, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | | | - Laurent Coscoy
- Division of Immunology and Molecular Medicine, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, 94720, USA
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8
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Elmasri Z, Negi V, Kuhn RJ, Jose J. Requirement of a functional ion channel for Sindbis virus glycoprotein transport, CPV-II formation, and efficient virus budding. PLoS Pathog 2022; 18:e1010892. [PMID: 36191050 PMCID: PMC9560593 DOI: 10.1371/journal.ppat.1010892] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 10/13/2022] [Accepted: 09/21/2022] [Indexed: 12/14/2022] Open
Abstract
Many viruses encode ion channel proteins that oligomerize to form hydrophilic pores in membranes of virus-infected cells and the viral membrane in some enveloped viruses. Alphavirus 6K, human immunodeficiency virus type 1 Vpu (HIV-Vpu), influenza A virus M2 (IAV-M2), and hepatitis C virus P7 (HCV-P7) are transmembrane ion channel proteins that play essential roles in virus assembly, budding, and entry. While the oligomeric structures and mechanisms of ion channel activity are well-established for M2 and P7, these remain unknown for 6K. Here we investigated the functional role of the ion channel activity of 6K in alphavirus assembly by utilizing a series of Sindbis virus (SINV) ion channel chimeras expressing the ion channel helix from Vpu or M2 or substituting the entire 6K protein with full-length P7, in cis. We demonstrate that the Vpu helix efficiently complements 6K, whereas M2 and P7 are less efficient. Our results indicate that while SINV is primarily insensitive to the M2 ion channel inhibitor amantadine, the Vpu inhibitor 5-N, N-Hexamethylene amiloride (HMA), significantly reduces SINV release, suggesting that the ion channel activity of 6K similar to Vpu, promotes virus budding. Using live-cell imaging of SINV with a miniSOG-tagged 6K and mCherry-tagged E2, we further demonstrate that 6K and E2 colocalize with the Golgi apparatus in the secretory pathway. To contextualize the localization of 6K in the Golgi, we analyzed cells infected with SINV and SINV-ion channel chimeras using transmission electron microscopy. Our results provide evidence for the first time for the functional role of 6K in type II cytopathic vacuoles (CPV-II) formation. We demonstrate that in the absence of 6K, CPV-II, which originates from the Golgi apparatus, is not detected in infected cells, with a concomitant reduction in the glycoprotein transport to the plasma membrane. Substituting a functional ion channel, M2 or Vpu localizing to Golgi, restores CPV-II production, whereas P7, retained in the ER, is inadequate to induce CPV-II formation. Altogether our results indicate that ion channel activity of 6K is required for the formation of CPV-II from the Golgi apparatus, promoting glycoprotein spike transport to the plasma membrane and efficient virus budding.
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Affiliation(s)
- Zeinab Elmasri
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Vashi Negi
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Richard J. Kuhn
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
- Markey Center for Structural Biology and Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, Indiana, United States of America
| | - Joyce Jose
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail:
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Islamuddin M, Mustfa SA, Ullah SNMN, Omer U, Kato K, Parveen S. Innate Immune Response and Inflammasome Activation During SARS-CoV-2 Infection. Inflammation 2022; 45:1849-1863. [PMID: 35953688 PMCID: PMC9371632 DOI: 10.1007/s10753-022-01651-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 02/12/2022] [Accepted: 02/15/2022] [Indexed: 11/05/2022]
Abstract
The novel coronavirus SARS-CoV-2, responsible for the COVID-19 outbreak, has become a pandemic threatening millions of lives worldwide. Recently, several vaccine candidates and drugs have shown promising effects in preventing or treating COVID-19, but due to the development of mutant strains through rapid viral evolution, urgent investigations are warranted in order to develop preventive measures and further improve current vaccine candidates. Positive-sense-single-stranded RNA viruses comprise many (re)emerging human pathogens that pose a public health problem. Our innate immune system and, in particular, the interferon response form an important first line of defense against these viruses. Flexibility in the genome aids the virus to develop multiple strategies to evade the innate immune response and efficiently promotes their replication and infective capacity. This review will focus on the innate immune response to SARS-CoV-2 infection and the virus' evasion of the innate immune system by escaping recognition or inhibiting the production of an antiviral state. Since interferons have been implicated in inflammatory diseases and immunopathology along with their protective role in infection, antagonizing the immune response may have an ambiguous effect on the clinical outcome of the viral disease. This pathology is characterized by intense, rapid stimulation of the innate immune response that triggers activation of the Nod-like receptor family, pyrin-domain-containing 3 (NLRP3) inflammasome pathway, and release of its products including the pro-inflammatory cytokines IL-6, IL-18, and IL-1β. This predictive view may aid in designing an immune intervention or preventive vaccine for COVID-19 in the near future.
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Affiliation(s)
- Mohammad Islamuddin
- Molecular Virology Laboratory, Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India.
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, Miyagi, Japan.
| | - Salman Ahmad Mustfa
- Centre for Craniofacial and Regenerative Biology, King's College London, Strand, London, UK
| | | | - Usmaan Omer
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Kentaro Kato
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, Miyagi, Japan
| | - Shama Parveen
- Molecular Virology Laboratory, Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
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Kakkanas A, Karamichali E, Koufogeorgou EI, Kotsakis SD, Georgopoulou U, Foka P. Targeting the YXXΦ Motifs of the SARS Coronaviruses 1 and 2 ORF3a Peptides by In Silico Analysis to Predict Novel Virus-Host Interactions. Biomolecules 2022; 12:1052. [PMID: 36008946 PMCID: PMC9405953 DOI: 10.3390/biom12081052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/21/2022] [Accepted: 07/25/2022] [Indexed: 02/08/2023] Open
Abstract
The emerging SARS-CoV and SARS-CoV-2 belong to the family of "common cold" RNA coronaviruses, and they are responsible for the 2003 epidemic and the current pandemic with over 6.3 M deaths worldwide. The ORF3a gene is conserved in both viruses and codes for the accessory protein ORF3a, with unclear functions, possibly related to viral virulence and pathogenesis. The tyrosine-based YXXΦ motif (Φ: bulky hydrophobic residue-L/I/M/V/F) was originally discovered to mediate clathrin-dependent endocytosis of membrane-spanning proteins. Many viruses employ the YXXΦ motif to achieve efficient receptor-guided internalisation in host cells, maintain the structural integrity of their capsids and enhance viral replication. Importantly, this motif has been recently identified on the ORF3a proteins of SARS-CoV and SARS-CoV-2. Given that the ORF3a aa sequence is not fully conserved between the two SARS viruses, we aimed to map in silico structural differences and putative sequence-driven alterations of regulatory elements within and adjacently to the YXXΦ motifs that could predict variations in ORF3a functions. Using robust bioinformatics tools, we investigated the presence of relevant post-translational modifications and the YXXΦ motif involvement in protein-protein interactions. Our study suggests that the predicted YXXΦ-related features may confer specific-yet to be discovered-functions to ORF3a proteins, significant to the new virus and related to enhanced propagation, host immune regulation and virulence.
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Affiliation(s)
- Athanassios Kakkanas
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Eirini Karamichali
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Efthymia Ioanna Koufogeorgou
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Stathis D. Kotsakis
- Laboratory of Bacteriology, Hellenic Pasteur Institute, 115-21 Athens, Greece;
| | - Urania Georgopoulou
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Pelagia Foka
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
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11
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Xia X, Cheng A, Wang M, Ou X, Sun D, Mao S, Huang J, Yang Q, Wu Y, Chen S, Zhang S, Zhu D, Jia R, Liu M, Zhao XX, Gao Q, Tian B. Functions of Viroporins in the Viral Life Cycle and Their Regulation of Host Cell Responses. Front Immunol 2022; 13:890549. [PMID: 35720341 PMCID: PMC9202500 DOI: 10.3389/fimmu.2022.890549] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022] Open
Abstract
Viroporins are virally encoded transmembrane proteins that are essential for viral pathogenicity and can participate in various stages of the viral life cycle, thereby promoting viral proliferation. Viroporins have multifaceted effects on host cell biological functions, including altering cell membrane permeability, triggering inflammasome formation, inducing apoptosis and autophagy, and evading immune responses, thereby ensuring that the virus completes its life cycle. Viroporins are also virulence factors, and their complete or partial deletion often reduces virion release and reduces viral pathogenicity, highlighting the important role of these proteins in the viral life cycle. Thus, viroporins represent a common drug-protein target for inhibiting drugs and the development of antiviral therapies. This article reviews current studies on the functions of viroporins in the viral life cycle and their regulation of host cell responses, with the aim of improving the understanding of this growing family of viral proteins.
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Affiliation(s)
- Xiaoyan Xia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Di Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Juan Huang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Dekang Zhu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Xin-Xin Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Bin Tian
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
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12
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Breitinger U, Farag NS, Sticht H, Breitinger HG. Viroporins: Structure, function, and their role in the life cycle of SARS-CoV-2. Int J Biochem Cell Biol 2022; 145:106185. [PMID: 35219876 PMCID: PMC8868010 DOI: 10.1016/j.biocel.2022.106185] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/15/2022] [Accepted: 02/21/2022] [Indexed: 12/12/2022]
Abstract
Viroporins are indispensable for viral replication. As intracellular ion channels they disturb pH gradients of organelles and allow Ca2+ flux across ER membranes. Viroporins interact with numerous intracellular proteins and pathways and can trigger inflammatory responses. Thus, they are relevant targets in the search for antiviral drugs. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) underlies the world-wide pandemic of COVID-19, where an effective therapy is still lacking despite impressive progress in the development of vaccines and vaccination campaigns. Among the 29 proteins of SARS-CoV-2, the E- and ORF3a proteins have been identified as viroporins that contribute to the massive release of inflammatory cytokines observed in COVID-19. Here, we describe structure and function of viroporins and their role in inflammasome activation and cellular processes during the virus replication cycle. Techniques to study viroporin function are presented, with a focus on cellular and electrophysiological assays. Contributions of SARS-CoV-2 viroporins to the viral life cycle are discussed with respect to their structure, channel function, binding partners, and their role in viral infection and virus replication. Viroporin sequences of new variants of concern (α–ο) of SARS-CoV-2 are briefly reviewed as they harbour changes in E and 3a proteins that may affect their function.
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Affiliation(s)
- Ulrike Breitinger
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Noha S Farag
- Department of Microbiology and Immunology, German University in Cairo, New Cairo, Egypt
| | - Heinrich Sticht
- Division of Bioinformatics, Institute for Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
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13
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Peñaflor-Téllez Y, Chávez-Munguía B, Lagunes-Guillén A, Salazar-Villatoro L, Gutiérrez-Escolano AL. The Feline Calicivirus Leader of the Capsid Protein Has the Functional Characteristics of a Viroporin. Viruses 2022; 14:v14030635. [PMID: 35337042 PMCID: PMC8955107 DOI: 10.3390/v14030635] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 12/27/2022] Open
Abstract
The leader of the capsid (LC) protein is exclusive to the Vesivirus genus, and it is needed for successful feline calicivirus (FCV) replication, as well as an efficient apoptosis induction through the mitochondrial pathway. In this work, we aimed to determine if the LC protein from the FCV is a viroporin. Although lacking in a transmembrane domain or an amphipathic helix, the LC protein from the FCV is toxic when expressed in bacteria and it oligomerizes through disulfide bonds, which are both key characteristics of viroporins. An electron microscopy analysis of LC-expressing E. coli cells suggest that the protein induces osmotic stress. Moreover, we found that the previously studied C40A LC mutant, that fails to induce apoptosis and that hinders the replication cycle, also oligomerizes but it has a reduced toxicity and fails to induce osmotic stress in bacteria. We propose that the LC protein is a viroporin that acts as a disulfide bond-dependent antimicrobial peptide, similar to the Ebola virus delta peptide.
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14
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Hepatitis C virus (HCV)-induced ROS/JNK signaling pathway activates the E3 ubiquitin ligase Itch to promote the release of HCV particles via polyubiquitylation of VPS4A. J Virol 2022; 96:e0181121. [PMID: 35044214 DOI: 10.1128/jvi.01811-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously reported that hepatitis C virus (HCV) infection activates the reactive oxygen species (ROS)/c-Jun N-terminal kinase (JNK) signaling pathway. However, the roles of ROS/JNK activation in the HCV life cycle still remain unclear. We sought to identify a novel role of ROS/JNK signaling pathway in the HCV life cycle. Immunoblot analysis revealed that HCV-induced ROS/JNK activation promoted phosphorylation of Itch, a HECT-type E3 ubiquitin ligase, leading to activation of Itch. The siRNA-knockdown of Itch significantly reduced the extracellular HCV infectivity titers, HCV RNA, and HCV core protein without affecting intracellular HCV infectivity titers, HCV RNA, and HCV proteins, suggesting that Itch is involved in release of HCV particles. HCV-mediated JNK/Itch activation specifically promoted polyubiquitylation of an AAA-type ATPase VPS4A, but not VPS4B, required to form multivesicular bodies. Site-directed mutagenesis revealed that two lysine residues (K23 and K121) on VPS4A were important for VPS4A polyubiquitylation. The siRNA-knockdown of VPS4A, but not VPS4B, significantly reduced extracellular HCV infectivity titers. Co-immunoprecipitation analysis revealed that HCV infection specifically enhanced the interaction between CHMP1B, a subunit of endosomal sorting complexes required for transport (ESCRT)-III complex, and VPS4A, but not VPS4B, whereas VPS4A K23R/K121R greatly reduced the interaction with CHMP1B. HCV infection significantly increased ATPase activity of VPS4A, but not VPS4A K23R/K121R or VPS4B, suggesting that HCV-mediated polyubiquitylation of VPS4A contributes to activation of VPS4A. Taken together, we propose that HCV-induced ROS/JNK/Itch signaling pathway promotes VPS4A polyubiquitylation, leading to enhanced VPS4A-CHMP1B interaction and promotion of VPS4A ATPase activity, thereby promoting the release of HCV particles. IMPORTANCE ROS/JNK signaling pathway contributes to liver diseases, including steatosis, metabolic disorders, and hepatocellular carcinoma. We previously reported that HCV activates the ROS/JNK signaling pathway, leading to the enhancement of hepatic gluconeogenesis and apoptosis induction. This study further demonstrates that HCV-induced ROS/JNK signaling pathway activates the E3 ubiquitin ligase Itch to promote release of HCV particles via polyubiquitylation of VPS4A. We provide evidence suggesting that HCV infection promotes the ROS/JNK/Itch signaling pathway and ESCRT/VPS4A machinery to release infectious HCV particles. Our results may lead to a better understanding of the mechanistic details of HCV particle release.
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15
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Gargan S, Stevenson NJ. Unravelling the Immunomodulatory Effects of Viral Ion Channels, towards the Treatment of Disease. Viruses 2021; 13:2165. [PMID: 34834972 PMCID: PMC8618147 DOI: 10.3390/v13112165] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/07/2021] [Accepted: 10/10/2021] [Indexed: 02/07/2023] Open
Abstract
The current COVID-19 pandemic has highlighted the need for the research community to develop a better understanding of viruses, in particular their modes of infection and replicative lifecycles, to aid in the development of novel vaccines and much needed anti-viral therapeutics. Several viruses express proteins capable of forming pores in host cellular membranes, termed "Viroporins". They are a family of small hydrophobic proteins, with at least one amphipathic domain, which characteristically form oligomeric structures with central hydrophilic domains. Consequently, they can facilitate the transport of ions through the hydrophilic core. Viroporins localise to host membranes such as the endoplasmic reticulum and regulate ion homeostasis creating a favourable environment for viral infection. Viroporins also contribute to viral immune evasion via several mechanisms. Given that viroporins are often essential for virion assembly and egress, and as their structural features tend to be evolutionarily conserved, they are attractive targets for anti-viral therapeutics. This review discusses the current knowledge of several viroporins, namely Influenza A virus (IAV) M2, Human Immunodeficiency Virus (HIV)-1 Viral protein U (Vpu), Hepatitis C Virus (HCV) p7, Human Papillomavirus (HPV)-16 E5, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) Open Reading Frame (ORF)3a and Polyomavirus agnoprotein. We highlight the intricate but broad immunomodulatory effects of these viroporins and discuss the current antiviral therapies that target them; continually highlighting the need for future investigations to focus on novel therapeutics in the treatment of existing and future emergent viruses.
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Affiliation(s)
- Siobhan Gargan
- Viral Immunology Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, D02 R590 Dublin, Ireland;
| | - Nigel J. Stevenson
- Viral Immunology Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, D02 R590 Dublin, Ireland;
- Viral Immunology Group, Royal College of Surgeons in Ireland-Medical University of Bahrain, Manama 15503, Bahrain
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16
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Liu Z, Zhang L, Cui T, Ma M, Ren J, Qu X. A Nature-Inspired Metal-Organic Framework Discriminator for Differential Diagnosis of Cancer Cell Subtypes. Angew Chem Int Ed Engl 2021; 60:15436-15444. [PMID: 33960090 DOI: 10.1002/anie.202102286] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Indexed: 12/13/2022]
Abstract
Metabolic glycan labeling (MGL) followed by bioorthogonal chemistry provides a powerful tool for tumor imaging and therapy. However, selectively metabolic labeling of cells or tissues of interest remains a challenge. Particularly, owing to tumor heterogeneity including tumor subtypes and interpatient heterogeneity, it is far more difficult to realize tumor-cell-selective metabolic labeling for precise diagnosis. Inspired by nature, we designed azidosugar-functionalized metal-organic frameworks camouflaged with cancer cell membranes to accomplish cancer-cell-selective MGL in vivo. With abundant receptors, this biomimetic platform not only selectively targets homotypic cells but also realizes different breast cancer subtype-selective MGL. Moreover, the endo/lysosomal-escaped ZIF-8 can make azidosugar escape from lysosomes and accelerate its metabolic incorporation. This strategy also takes advantage of cancer-tissue-derived cell membranes, which may have huge potential for personalized diagnosis and therapy.
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Affiliation(s)
- Zhengwei Liu
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100039, P. R. China
| | - Lu Zhang
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100039, P. R. China
| | - Tingting Cui
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.,University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Mengmeng Ma
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.,University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Jinsong Ren
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.,University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Xiaogang Qu
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.,University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
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17
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Liu Z, Zhang L, Cui T, Ma M, Ren J, Qu X. A Nature‐Inspired Metal–Organic Framework Discriminator for Differential Diagnosis of Cancer Cell Subtypes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102286] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Zhengwei Liu
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Chinese Academy of Sciences Beijing 100039 P. R. China
| | - Lu Zhang
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Chinese Academy of Sciences Beijing 100039 P. R. China
| | - Tingting Cui
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Mengmeng Ma
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Jinsong Ren
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Xiaogang Qu
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Science and Technology of China Hefei Anhui 230026 P. R. China
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18
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Cabrera‐Garcia D, Bekdash R, Abbott GW, Yazawa M, Harrison NL. The envelope protein of SARS-CoV-2 increases intra-Golgi pH and forms a cation channel that is regulated by pH. J Physiol 2021; 599:2851-2868. [PMID: 33709461 PMCID: PMC8251088 DOI: 10.1113/jp281037] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 03/02/2021] [Indexed: 12/19/2022] Open
Abstract
KEY POINTS We report a novel method for the transient expression of SARS-CoV-2 envelope (E) protein in intracellular organelles and the plasma membrane of mammalian cells and Xenopus oocytes. Intracellular expression of SARS-CoV-2 E protein increases intra-Golgi pH. By targeting the SARS-CoV-2 E protein to the plasma membrane, we show that it forms a cation channel, viroporin, that is modulated by changes of pH. This method for studying the activity of viroporins may facilitate screening for new antiviral drugs to identify novel treatments for COVID-19. ABSTRACT The envelope (E) protein of coronaviruses such as SARS-CoV-1 is proposed to form an ion channel or viroporin that participates in viral propagation and pathogenesis. Here we developed a technique to study the E protein of SARS-CoV-2 in mammalian cells by directed targeting using a carboxyl-terminal fluorescent protein tag, mKate2. The wild-type SARS-CoV-2 E protein can be trafficked to intracellular organelles, notably the endoplasmic reticulum-Golgi intermediate complex, where its expression increases pH inside the organelle. We also succeeded in targeting SARS-CoV-2 E to the plasma membrane, which enabled biophysical analysis using whole-cell patch clamp recording in a mammalian cell line, HEK 293 cells, and two-electrode voltage clamp electrophysiology in Xenopus oocytes. The results suggest that the E protein forms an ion channel that is permeable to monovalent cations such as Na+ , Cs+ and K+ . The E current is nearly time- and voltage-independent when E protein is expressed in mammalian cells, and is modulated by changes of pH. At pH 6.0 and 7.4, the E protein current is activated, whereas at pH 8.0 and 9.0, the amplitude of E protein current is reduced, and in oocytes the inward E current fades at pH 9 in a time- and voltage-dependent manner. Using this directed targeting method and electrophysiological recordings, potential inhibitors of the E protein can be screened and subsequently investigated for antiviral activity against SARS-CoV-2 in vitro and possible efficacy in treating COVID-19.
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Affiliation(s)
| | - Ramsey Bekdash
- Department of Molecular Pharmacology and TherapeuticsColumbia UniversityNew YorkNYUSA
- Columbia Stem Cell Initiative, Department of Rehabilitation and Regenerative MedicineColumbia UniversityNew YorkNYUSA
| | - Geoffrey W. Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of MedicineUniversity of CaliforniaIrvineCAUSA
| | - Masayuki Yazawa
- Department of Molecular Pharmacology and TherapeuticsColumbia UniversityNew YorkNYUSA
- Columbia Stem Cell Initiative, Department of Rehabilitation and Regenerative MedicineColumbia UniversityNew YorkNYUSA
| | - Neil L. Harrison
- Department of AnesthesiologyColumbia UniversityNew YorkNYUSA
- Department of Molecular Pharmacology and TherapeuticsColumbia UniversityNew YorkNYUSA
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19
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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.
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20
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Wozniak AL, Adams A, King KE, Dunn W, Christenson LK, Hung WT, Weinman SA. The RNA binding protein FMR1 controls selective exosomal miRNA cargo loading during inflammation. J Cell Biol 2021; 219:152116. [PMID: 32970791 PMCID: PMC7659717 DOI: 10.1083/jcb.201912074] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 04/22/2020] [Accepted: 07/09/2020] [Indexed: 12/16/2022] Open
Abstract
Cells respond to inflammatory disease states by releasing exosomes containing highly specific protein and RNA cargos, but how inflammation alters cargo specificity and secretion of exosomes is unknown. We show that increases in exosome secretion induced by either viral infection or LPS/ATP exposure result from inflammasome activation and subsequent caspase-1–dependent cleavage of the trafficking adaptor protein RILP. This cleaved form of RILP promotes the movement of multivesicular bodies toward the cell periphery and induces selective exosomal miRNA cargo loading. We have identified a common short sequence motif present in miRNAs that are selectively loaded into exosomes after RILP cleavage. This motif binds the RNA binding protein FMR1 and directs miRNA loading into exosomes via interaction with components of the ESCRT (endosomal sorting complex required for transport) pathway. These results indicate that inflammasome-mediated RILP cleavage, and sequence-specific interactions between miRNAs and FMR1, play a significant role in exosome cargo loading and enhanced secretion during cellular inflammatory responses.
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Affiliation(s)
- Ann L Wozniak
- Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS.,Liver Center, University of Kansas Medical Center, Kansas City KS
| | - Abby Adams
- Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS.,Liver Center, University of Kansas Medical Center, Kansas City KS
| | - Kayla E King
- Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS.,Liver Center, University of Kansas Medical Center, Kansas City KS
| | - Winston Dunn
- Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS.,Liver Center, University of Kansas Medical Center, Kansas City KS
| | - Lane K Christenson
- Department of Molecular & Integrative Physiology, University of Kansas Medical Center, Kansas City KS
| | - Wei-Ting Hung
- Department of Molecular & Integrative Physiology, University of Kansas Medical Center, Kansas City KS.,Center for Systems Biology, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Steven A Weinman
- Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS.,Liver Center, University of Kansas Medical Center, Kansas City KS
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21
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Breitinger U, Farag NS, Ali NKM, Ahmed M, El-Azizi MA, Breitinger HG. Cell viability assay as a tool to study activity and inhibition of hepatitis C p7 channels. J Gen Virol 2021; 102. [PMID: 33709903 DOI: 10.1099/jgv.0.001571] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The p7 viroporin of the hepatitis C virus (HCV) forms an intracellular proton-conducting transmembrane channel in virus-infected cells, shunting the pH of intracellular compartments and thus helping virus assembly and release. This activity is essential for virus infectivity, making viroporins an attractive target for drug development. The protein sequence and drug sensitivity of p7 vary between the seven major genotypes of the hepatitis C virus, but the essential channel activity is preserved. Here, we investigated the effect of several inhibitors on recombinant HCV p7 channels corresponding to genotypes 1a-b, 2a-b, 3a and 4a using patch-clamp electrophysiology and cell-based assays. We established a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-based cell viability assay for recombinant p7 expressed in HEK293 cells to assess channel activity and its sensitivity to inhibitors. The results from the cell viability assay were consistent with control measurements using established assays of haemadsorption and intracellular pH, and agreed with data from patch-clamp electrophysiology. Hexamethylene amiloride (HMA) was the most potent inhibitor of p7 activity, but possessed cytotoxic activity at higher concentrations. Rimantadine was active against p7 of all genotypes, while amantadine activity was genotype-dependent. The alkyl-chain iminosugars NB-DNJ, NN-DNJ and NN-DGJ were tested and their activity was found to be genotype-specific. In the current study, we introduce cell viability assays as a rapid and cost-efficient technique to assess viroporin activity and identify channel inhibitors as potential novel antiviral drugs.
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Affiliation(s)
- Ulrike Breitinger
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Noha S Farag
- Department of Microbiology and Immunology, German University in Cairo, New Cairo, Egypt
| | - Nourhan K M Ali
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Marwa Ahmed
- Present address: Institute of Biochemistry and Biophysics Friedrich-Schiller-University Jena, Hans-Knöll-Str. 2, D-07745, Jena, Germany.,Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Mohamed A El-Azizi
- Department of Microbiology and Immunology, German University in Cairo, New Cairo, Egypt
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22
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Zaloilo I, Rud Y, Zaloilo О, Buchatskyi L. Coronavirus viroporins: structure and function. UKRAINIAN BIOCHEMICAL JOURNAL 2021. [DOI: 10.15407/ubj93.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Viroporins are involved in viral pathogenesis, play an important role in the morphogenesis of virions and ensure their release from the infected cell. These proteins are potentially promising as possible targets for the regulation of virus reproduction. The literature data on the current understanding of coronavirus viroporins functioning are summarized in the review. Special attention is focused on specific structural features that determine the functional ability of these proteins. The basic principles of viroporins localization in the cell and their influence on the coronavirus life cycle are considered. Keywords: coronavirus, pore formation, protein 3a, protein 8a, protein E, SARS, viroporins
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23
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Shaw J, Gosain R, Kalita MM, Foster TL, Kankanala J, Mahato DR, Abas S, King BJ, Scott C, Brown E, Bentham MJ, Wetherill L, Bloy A, Samson A, Harris M, Mankouri J, Rowlands DJ, Macdonald A, Tarr AW, Fischer WB, Foster R, Griffin S. Rationally derived inhibitors of hepatitis C virus (HCV) p7 channel activity reveal prospect for bimodal antiviral therapy. eLife 2020; 9:e52555. [PMID: 33169665 PMCID: PMC7714397 DOI: 10.7554/elife.52555] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 11/09/2020] [Indexed: 12/26/2022] Open
Abstract
Since the 1960s, a single class of agent has been licensed targeting virus-encoded ion channels, or 'viroporins', contrasting the success of channel blocking drugs in other areas of medicine. Although resistance arose to these prototypic adamantane inhibitors of the influenza A virus (IAV) M2 proton channel, a growing number of clinically and economically important viruses are now recognised to encode essential viroporins providing potential targets for modern drug discovery. We describe the first rationally designed viroporin inhibitor with a comprehensive structure-activity relationship (SAR). This step-change in understanding not only revealed a second biological function for the p7 viroporin from hepatitis C virus (HCV) during virus entry, but also enabled the synthesis of a labelled tool compound that retained biological activity. Hence, p7 inhibitors (p7i) represent a unique class of HCV antiviral targeting both the spread and establishment of infection, as well as a precedent for future viroporin-targeted drug discovery.
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Affiliation(s)
- Joseph Shaw
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Rajendra Gosain
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Monoj Mon Kalita
- Institute of Biophotonics, National Yang-Ming UniversityTaipeiTaiwan
| | - Toshana L Foster
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Jayakanth Kankanala
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - D Ram Mahato
- Institute of Biophotonics, National Yang-Ming UniversityTaipeiTaiwan
| | - Sonia Abas
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Barnabas J King
- School of Life Sciences, Faculty of Medicine & Health Sciences, University of Nottingham, Queen's Medical CentreNottinghamUnited Kingdom
| | - Claire Scott
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Emma Brown
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Matthew J Bentham
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Laura Wetherill
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Abigail Bloy
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Adel Samson
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
| | - Mark Harris
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Jamel Mankouri
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - David J Rowlands
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Andrew Macdonald
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Alexander W Tarr
- School of Life Sciences, Faculty of Medicine & Health Sciences, University of Nottingham, Queen's Medical CentreNottinghamUnited Kingdom
| | | | - Richard Foster
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Stephen Griffin
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
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24
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Ins and Outs of Reovirus: Vesicular Trafficking in Viral Entry and Egress. Trends Microbiol 2020; 29:363-375. [PMID: 33008713 PMCID: PMC7523517 DOI: 10.1016/j.tim.2020.09.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 12/11/2022]
Abstract
Cell entry and egress are essential steps in the viral life cycle that govern pathogenesis and spread. Mammalian orthoreoviruses (reoviruses) are nonenveloped viruses implicated in human disease that serve as tractable models for studies of pathogen-host interactions. In this review we discuss the function of intracellular vesicular transport systems in reovirus entry, trafficking, and egress and comment on shared themes for diverse viruses. Designing strategic therapeutic interventions that impede these steps in viral replication requires a detailed understanding of mechanisms by which viruses coopt vesicular trafficking. We illuminate such targets, which may foster development of antiviral agents.
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25
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Alzahrani N, Wu MJ, Shanmugam S, Yi M. Delayed by Design: Role of Suboptimal Signal Peptidase Processing of Viral Structural Protein Precursors in Flaviviridae Virus Assembly. Viruses 2020; 12:v12101090. [PMID: 32993149 PMCID: PMC7601889 DOI: 10.3390/v12101090] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/04/2020] [Accepted: 09/24/2020] [Indexed: 02/06/2023] Open
Abstract
The Flaviviridae virus family is classified into four different genera, including flavivirus, hepacivirus, pegivirus, and pestivirus, which cause significant morbidity and mortality in humans and other mammals, including ruminants and pigs. These are enveloped, single-stranded RNA viruses sharing a similar genome organization and replication scheme with certain unique features that differentiate them. All viruses in this family express a single polyprotein that encodes structural and nonstructural proteins at the N- and C-terminal regions, respectively. In general, the host signal peptidase cleaves the structural protein junction sites, while virus-encoded proteases process the nonstructural polyprotein region. It is known that signal peptidase processing is a rapid, co-translational event. Interestingly, certain signal peptidase processing site(s) in different Flaviviridae viral structural protein precursors display suboptimal cleavage kinetics. This review focuses on the recent progress regarding the Flaviviridae virus genus-specific mechanisms to downregulate signal peptidase-mediated processing at particular viral polyprotein junction sites and the role of delayed processing at these sites in infectious virus particle assembly.
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26
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Cao Y, Yang R, Wang W, Lee I, Zhang R, Zhang W, Sun J, Xu B, Meng X. Computational Study of the Ion and Water Permeation and Transport Mechanisms of the SARS-CoV-2 Pentameric E Protein Channel. Front Mol Biosci 2020; 7:565797. [PMID: 33173781 PMCID: PMC7538787 DOI: 10.3389/fmolb.2020.565797] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/04/2020] [Indexed: 12/28/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus (SARS-CoV-2) and represents the causative agent of a potentially fatal disease that is a public health emergency of international concern. Coronaviruses, including SARS-CoV-2, encode an envelope (E) protein, which is a small, hydrophobic membrane protein; the E protein of SARS-CoV-2 shares a high level of homology with severe acute respiratory syndrome coronavirus (SARS-CoV). In this study, we provide insights into the function of the SARS-CoV-2 E protein channel and the ion and water permeation mechanisms using a combination of in silico methods. Based on our results, the pentameric E protein promotes the penetration of cation ions through the channel. An analysis of the potential mean force (PMF), pore radius and diffusion coefficient reveals that Leu10 and Phe19 are the hydrophobic gates of the channel. In addition, the pore exhibits a clear wetting/dewetting transition with cation selectivity under transmembrane voltage, indicating that it is a hydrophobic voltage-dependent channel. Overall, these results provide structure-based insights and molecular dynamic information that are needed to understand the regulatory mechanisms of ion permeability in the pentameric SARS-CoV-2 E protein channel.
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Affiliation(s)
- Yipeng Cao
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, China.,National Supercomputer Center in Tianjin, TEDA - Tianjin Economic-Technological Development Area, Tianjin, China
| | - Rui Yang
- Department of Infection and Immunity, Tianjin Union Medical Center, Nankai University Affiliated Hospital, Tianjin, China
| | - Wei Wang
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China
| | - Imshik Lee
- College of Physics, Nankai University, Tianjin, China
| | - Ruiping Zhang
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Wenwen Zhang
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Jiana Sun
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Bo Xu
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China.,Center for Intelligent Oncology, Chongqing University School of Medicine and Chongqing University Cancer Hospital, Chongqing, China
| | - Xiangfei Meng
- National Supercomputer Center in Tianjin, TEDA - Tianjin Economic-Technological Development Area, Tianjin, China
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27
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Bouayad A. Innate immune evasion by SARS-CoV-2: Comparison with SARS-CoV. Rev Med Virol 2020; 30:1-9. [PMID: 32734714 DOI: 10.1002/rmv.2135] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 05/27/2020] [Accepted: 05/28/2020] [Indexed: 02/06/2023]
Abstract
SARS-CoV-2 virus, a member of the Coronaviridae family, causes Covid-19 pandemic disease with severe respiratory illness. Multiple strategies enable SARS-CoV-2 to eventually overcome antiviral innate immune mechanisms which are important components of viral pathogenesis. This review considers several mechanisms of SARS-CoV-2 innate immune evasion including suppression of IFN-α/β production at the earliest stage of infection, mechanisms that exhaust natural killer cell-mediated cytotoxicity, overstimulation of NLRP3 inflammasome and induction of a cytokine storm. A comparison with SARS-CoV is made. Greater knowledge of these and other immune evasion tactics may provide us with improved possibilities for research into this novel deadly virus.
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Affiliation(s)
- Abdellatif Bouayad
- Laboratory of Immunohematology and Cellular Therapy, Faculty of Medicine and Pharmacy, Mohammed First University, Oujda, Morocco.,Laboratory of Immunology, Mohammed VI Hospital, Oujda, Morocco
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28
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Farag NS, Breitinger U, Breitinger HG, El Azizi MA. Viroporins and inflammasomes: A key to understand virus-induced inflammation. Int J Biochem Cell Biol 2020; 122:105738. [PMID: 32156572 PMCID: PMC7102644 DOI: 10.1016/j.biocel.2020.105738] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 02/07/2023]
Abstract
The article provides a summary on cellular receptors involved in virus immunity. It summarizes key findings on viroporins, a novel class of viral proteins and their role in the virus life cycle and host cell interactions. It presents an overview of the current understanding of inflammasomes complex activation, with special focus on NLRP3. It discusses the correlation between viroporins and inflammasomes activation and aggravated inflammatory cytokines production.
Viroporins are virus encoded proteins that alter membrane permeability and can trigger subsequent cellular signals. Oligomerization of viroporin subunits results in formation of a hydrophilic pore which facilitates ion transport across host cell membranes. These viral channel proteins may be involved in different stages of the virus infection cycle. Inflammasomes are large multimolecular complexes best recognized for their ability to control activation of caspase-1, which in turn regulates the maturation of interleukin-1 β (IL-1β) and interleukin 18 (IL-18). IL-1β was originally identified as a pro-inflammatory cytokine able to induce both local and systemic inflammation and a febrile reaction in response to infection or injury. Excessive production of IL-1β is associated with autoimmune and inflammatory diseases. Microbial derivatives, bacterial pore-forming toxins, extracellular ATP and other pathogen-associated molecular patterns trigger activation of NLRP3 inflammasomes. Recent studies have reported that viroporin activity is capable of inducing inflammasome activity and production of IL-1β, where NLRP3 is shown to be regulated by fluxes of K+, H+ and Ca2+ in addition to reactive oxygen species, autophagy and endoplasmic reticulum stress. The aim of this review is to present an overview of the key findings on viroporin activity with special emphasis on their role in virus immunity and as possible activators of inflammasomes.
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Affiliation(s)
- N S Farag
- Department of Microbiology and Immunology, German University inCairo, New Cairo, Egypt.
| | - U Breitinger
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - H G Breitinger
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - M A El Azizi
- Department of Microbiology and Immunology, German University inCairo, New Cairo, Egypt
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29
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Abstract
Maintenance of the main Golgi functions, glycosylation and sorting, is dependent on the unique Golgi pH microenvironment that is thought to be set by the balance between the rates of V-ATPase-mediated proton pumping and its leakage back to the cytoplasm via an unknown pathway. The concentration of other ions, such as chloride, potassium, calcium, magnesium, and manganese, is also important for Golgi homeostasis and dependent on the transport activity of other ion transporters present in the Golgi membranes. During the last decade, several new disorders have been identified that are caused by, or are associated with, dysregulated Golgi pH and ion homeostasis. Here, we will provide an updated overview on these disorders and the proteins involved. We will also discuss other disorders for which the molecular defects remain currently uncertain but which potentially involve proteins that regulate Golgi pH or ion homeostasis.
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30
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Pang S, Zhao R, Wang S, Wang J. Cyclopeptides design as blockers against HCV p7 channel in silico. MOLECULAR SIMULATION 2019. [DOI: 10.1080/08927022.2019.1641604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Shichao Pang
- Department of Statistics, School of Mathematical Sciences, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Rongcheng Zhao
- Cangzhou Central Hospital, Cardiovascular Ward I, Cangzhou, People’s Republic of China
| | - Shuqing Wang
- School of Pharmacy, Tianjin Medical University, Tianjin, People’s Republic of China
| | - Jingfang Wang
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai, People’s Republic of China
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai, People’s Republic of China
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31
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Soares HR, Ferreira-Fernandes M, Almeida AI, Marchel M, Alves PM, Coroadinha AS. Enhancing Hepatitis C virus pseudoparticles infectivity through p7NS2 cellular expression. J Virol Methods 2019; 274:113714. [PMID: 31412271 DOI: 10.1016/j.jviromet.2019.113714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 07/30/2019] [Accepted: 08/09/2019] [Indexed: 12/27/2022]
Abstract
Hepatitis C pseudoparticles (HCVpp) are used to evaluate HCV cell entry while screening for neutralizing antibodies induced upon vaccination or while screening for new antiviral drugs. In this work we explore the stable production of HCVpp aiming to reduce the variability associated with transient productions. The performance of stably produced HCVpp was assessed by evaluating the influence of Human Serum and the impact of CD81 cellular expression on the infectivity of HCVpp. After evaluating the performance of stably produced HCVpp we studied the effect of co-expressing p7NS2 openreading frame (ORF) on HCVpp infectivity. Our data clearly shows an enhanced infectivity of HCVppp7NS2. Even though the exact mechanism was not completely elucidated, the enhanced infectivity of HCVppp7NS2 is neither a result of an increase production of virus particles nor a result from increased envelope density. The inhibitory effect of p7 inhibitory molecules such as rimantadine suggests a direct contribution of p7 ion channel for the enhanced infectivity of HCVppp7NS2 which is coherent with a pH-dependent cell entry mechanism. In conclusion, we report the establishment of a stable production system of HCVpp with enhanced infectivity through the overexpression of p7NS2 ORF contributing to improve HCV entry assessment assays widely used in antiviral drug discovery and vaccine development.
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Affiliation(s)
- Hugo R Soares
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Marina Ferreira-Fernandes
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Ana I Almeida
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Mateusz Marchel
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal; Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Paula M Alves
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Ana S Coroadinha
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal.
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32
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Jones-Jamtgaard KN, Wozniak AL, Koga H, Ralston R, Weinman SA. Hepatitis C virus infection increases autophagosome stability by suppressing lysosomal fusion through an Arl8b-dependent mechanism. J Biol Chem 2019; 294:14257-14266. [PMID: 31383738 DOI: 10.1074/jbc.ra119.008229] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 07/22/2019] [Indexed: 12/13/2022] Open
Abstract
Autophagy is a conserved cellular process involving intracellular membrane trafficking and degradation. Pathogens, including hepatitis C virus (HCV), often exploit this process to promote their own survival. The aim of this study was to determine the mechanism by which HCV increases steady-state autophagosome numbers while simultaneously inhibiting flux through the autophagic pathway. Using the lysosomal inhibitor bafilomycin A1, we showed that HCV-induced alterations in autophagy result from a blockage of autophagosome degradation rather than an increase in autophagosome generation. In HCV-infected cells, lysosome function was normal, but a tandem RFP-GFP-LC3 failed to reach the lysosome even under conditions that activate autophagy. Autophagosomes and lysosomes isolated from HCV-infected cells were able to fuse with each other normally in vitro, suggesting that the cellular fusion defect resulted from trafficking rather than an inability of vesicles to fuse. Arl8b is an Arf-like GTPase that specifically localizes to lysosomes and plays a role in autophagic flux through its effect on lysosomal positioning. At basal levels, Arl8b was primarily found in a perinuclear localization and co-localized with LC3-positive autophagosomes. HCV infection increased the level of Arl8b 3-fold and redistributed Arl8b to a more diffuse, peripheral pattern that failed to co-localize with LC3. Knockdown of Arl8b in HCV-infected cells restored autophagosome-lysosome fusion and autophagic flux to levels seen in control cells. Thus, HCV suppresses autophagic flux and increases the steady-state levels of autophagosomes by increasing the expression of Arl8b, which repositions lysosomes and prevents their fusion with autophagosomes.
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Affiliation(s)
- Kellyann N Jones-Jamtgaard
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kansas Medical Center, Kansas City, Kansas 66160
| | - Ann L Wozniak
- Department of Internal Medicine and Liver Center, University of Kansas Medical Center, Kansas City, Kansas 66160
| | - Hiroshi Koga
- Department of Developmental and Molecular Biology and Marion Bessin Liver Research Center, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Robert Ralston
- Department of Pharmacology and Toxicology, University of Kansas Medical Center, Kansas City, Kansas 66160
| | - Steven A Weinman
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kansas Medical Center, Kansas City, Kansas 66160 .,Department of Internal Medicine and Liver Center, University of Kansas Medical Center, Kansas City, Kansas 66160
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33
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Westerbeck JW, Machamer CE. The Infectious Bronchitis Coronavirus Envelope Protein Alters Golgi pH To Protect the Spike Protein and Promote the Release of Infectious Virus. J Virol 2019; 93:e00015-19. [PMID: 30867314 PMCID: PMC6532078 DOI: 10.1128/jvi.00015-19] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/07/2019] [Indexed: 12/20/2022] Open
Abstract
Coronaviruses (CoVs) assemble by budding into the lumen of the early Golgi complex prior to exocytosis. The small CoV envelope (E) protein plays roles in assembly, virion release, and pathogenesis. CoV E has a single hydrophobic domain (HD), is targeted to Golgi membranes, and has cation channel activity in vitro The E protein from avian infectious bronchitis virus (IBV) has dramatic effects on the secretory system, which require residues in the HD. Mutation of the HD of IBV E in a recombinant virus background results in impaired growth kinetics, impaired release of infectious virions, accumulation of IBV spike (S) protein on the plasma membrane compared to wild-type (WT) IBV-infected cells, and aberrant cleavage of IBV S on virions. We previously reported the formation of two distinct oligomeric pools of IBV E in transfected and infected cells. Disruption of the secretory pathway by IBV E correlates with a form that is likely monomeric, suggesting that the effects on the secretory pathway are independent of E ion channel activity. Here, we present evidence suggesting that the monomeric form of IBV E correlates with an increased Golgi luminal pH. Infection with IBV or expression of IBV E induces neutralization of Golgi pH, promoting a model in which IBV E alters the secretory pathway through interaction with host cell factors, protecting IBV S from premature cleavage and leading to the efficient release of infectious virus from the cells. This is the first demonstration of a coronavirus-induced alteration in the microenvironment of the secretory pathway.IMPORTANCE Coronaviruses are important human pathogens with significant zoonotic potential. Progress has been made toward identifying potential vaccine candidates for highly pathogenic human CoVs, including the use of attenuated viruses that lack the CoV E protein or express E mutants. However, no approved vaccines or antiviral therapeutics exist. Understanding the role of the CoV E protein in virus assembly and release is thus an important prerequisite for potential vaccines as well as in identifying novel antiviral therapeutics.
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Affiliation(s)
- Jason W Westerbeck
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Carolyn E Machamer
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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34
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Abstract
BACKGROUND Coronaviruses (CoVs) primarily cause enzootic infections in birds and mammals but, in the last few decades, have shown to be capable of infecting humans as well. The outbreak of severe acute respiratory syndrome (SARS) in 2003 and, more recently, Middle-East respiratory syndrome (MERS) has demonstrated the lethality of CoVs when they cross the species barrier and infect humans. A renewed interest in coronaviral research has led to the discovery of several novel human CoVs and since then much progress has been made in understanding the CoV life cycle. The CoV envelope (E) protein is a small, integral membrane protein involved in several aspects of the virus' life cycle, such as assembly, budding, envelope formation, and pathogenesis. Recent studies have expanded on its structural motifs and topology, its functions as an ion-channelling viroporin, and its interactions with both other CoV proteins and host cell proteins. MAIN BODY This review aims to establish the current knowledge on CoV E by highlighting the recent progress that has been made and comparing it to previous knowledge. It also compares E to other viral proteins of a similar nature to speculate the relevance of these new findings. Good progress has been made but much still remains unknown and this review has identified some gaps in the current knowledge and made suggestions for consideration in future research. CONCLUSIONS The most progress has been made on SARS-CoV E, highlighting specific structural requirements for its functions in the CoV life cycle as well as mechanisms behind its pathogenesis. Data shows that E is involved in critical aspects of the viral life cycle and that CoVs lacking E make promising vaccine candidates. The high mortality rate of certain CoVs, along with their ease of transmission, underpins the need for more research into CoV molecular biology which can aid in the production of effective anti-coronaviral agents for both human CoVs and enzootic CoVs.
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Affiliation(s)
- Dewald Schoeman
- Molecular Biology and Virology Research Laboratory, Department of Medical Biosciences, University of the Western Cape, Cape Town, South Africa
| | - Burtram C Fielding
- Molecular Biology and Virology Research Laboratory, Department of Medical Biosciences, University of the Western Cape, Cape Town, South Africa.
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35
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Alazard-Dany N, Denolly S, Boson B, Cosset FL. Overview of HCV Life Cycle with a Special Focus on Current and Possible Future Antiviral Targets. Viruses 2019; 11:v11010030. [PMID: 30621318 PMCID: PMC6356578 DOI: 10.3390/v11010030] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 12/31/2018] [Accepted: 01/02/2019] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C infection is the leading cause of liver diseases worldwide and a major health concern that affects an estimated 3% of the global population. Novel therapies available since 2014 and 2017 are very efficient and the WHO considers HCV eradication possible by the year 2030. These treatments are based on the so-called direct acting antivirals (DAAs) that have been developed through research efforts by academia and industry since the 1990s. After a brief overview of the HCV life cycle, we describe here the functions of the different targets of current DAAs, the mode of action of these DAAs and potential future inhibitors.
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Affiliation(s)
- Nathalie Alazard-Dany
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France.
| | - Solène Denolly
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France.
| | - Bertrand Boson
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France.
| | - François-Loïc Cosset
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France.
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Computational Study of HCV p7 Channel: Insight into a New Strategy for HCV Inhibitor Design. Interdiscip Sci 2018; 11:292-299. [PMID: 30194627 DOI: 10.1007/s12539-018-0306-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 07/23/2018] [Accepted: 09/03/2018] [Indexed: 10/28/2022]
Abstract
HCV p7 protein is a cation-selective ion channel, playing an essential role during the life cycle of HCV viruses. To understand the cation-selective mechanism, we constructed a hexameric model in lipid bilayers of HCV p7 protein for HCB JFH-1 strain, genotype 2a. In this structural model, His9 and Val6 were key factors for the HCV cation-selective ion channel. The histidine residues at position 9 in the hexameric model formed a first gate for HCV p7 channel, acting as a selectivity filter for cations. The valines mentioned above formed a second gate for HCV p7 channel, serving as a hydrophobic filter for the dehydrated cations. The binding pocket for the channel blockers, e.g., amantadine and rimantadine, was composed of residues 20-26 in H2 helix and 52-60 in H3 helix in i + 2 monomer. However, the molecular volumes for both amantadine and rimantadine were too small for the binding pocket of HCV p7 channel. Thus, designing a compound similar with rimantadine and having much larger volume would be an effective strategy for discovering inhibitors against HCV p7 channel. To achieve this point, we used rimantadine as a structural template to search ChEMBL database for the candidates employing favorable binding affinities to HCV p7 channel. As a result, six candidates were identified to have potential to be novel inhibitors against HCV p7 channel.
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Shiryaev VA, Radchenko EV, Palyulin VA, Zefirov NS, Bormotov NI, Serova OA, Shishkina LN, Baimuratov MR, Bormasheva KM, Gruzd YA, Ivleva EA, Leonova MV, Lukashenko AV, Osipov DV, Osyanin VA, Reznikov AN, Shadrikova VA, Sibiryakova AE, Tkachenko IM, Klimochkin YN. Molecular design, synthesis and biological evaluation of cage compound-based inhibitors of hepatitis C virus p7 ion channels. Eur J Med Chem 2018; 158:214-235. [PMID: 30218908 DOI: 10.1016/j.ejmech.2018.08.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/04/2018] [Accepted: 08/03/2018] [Indexed: 12/14/2022]
Abstract
The hepatitis C caused by the hepatitis C virus (HCV) is an acute and/or chronic liver disease ranging in severity from a mild brief ailment to a serious lifelong illness that affects up to 3% of the world population and imposes significant and increasing social, economic, and humanistic burden. Over the past decade, its treatment was revolutionized by the development and introduction into clinical practice of the direct acting antiviral (DAA) agents targeting the non-structural viral proteins NS3/4A, NS5A, and NS5B. However, the current treatment options still have important limitations, thus, the development of new classes of DAAs acting on different viral targets and having better pharmacological profile is highly desirable. The hepatitis C virus p7 viroporin is a relatively small hydrophobic oligomeric viral ion channel that plays a critical role during virus assembly and maturation, making it an attractive and validated target for the development of the cage compound-based inhibitors. Using the homology modeling, molecular dynamics, and molecular docking techniques, we have built a representative set of models of the hepatitis C virus p7 ion channels (Gt1a, Gt1b, Gt1b_L20F, Gt2a, and Gt2b), analyzed the inhibitor binding sites, and identified a number of potential broad-spectrum inhibitor structures targeting them. For one promising compound, the binding to these targets was additionally confirmed and the binding modes and probable mechanisms of action were clarified by the molecular dynamics simulations. A number of compounds were synthesized, and the tests of their antiviral activity (using the BVDV model) and cytotoxicity demonstrate their potential therapeutic usefulness and encourage further more detailed studies. The proposed approach is also suitable for the design of broad-spectrum ligands interacting with other multiple labile targets including various viroporins.
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Affiliation(s)
- Vadim A Shiryaev
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia.
| | - Eugene V Radchenko
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow, 119991, Russia
| | - Vladimir A Palyulin
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow, 119991, Russia
| | - Nikolay S Zefirov
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow, 119991, Russia
| | - Nikolay I Bormotov
- State Research Center of Virology and Biotechnology 'Vector', Koltsovo, Novosibirsk Region, 630559, Russia
| | - Olga A Serova
- State Research Center of Virology and Biotechnology 'Vector', Koltsovo, Novosibirsk Region, 630559, Russia
| | - Larisa N Shishkina
- State Research Center of Virology and Biotechnology 'Vector', Koltsovo, Novosibirsk Region, 630559, Russia
| | - Marat R Baimuratov
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Kseniya M Bormasheva
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Yulia A Gruzd
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Elena A Ivleva
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Marina V Leonova
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Anton V Lukashenko
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Dmitry V Osipov
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Vitaliy A Osyanin
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Alexander N Reznikov
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Vera A Shadrikova
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Anastasia E Sibiryakova
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Ilya M Tkachenko
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
| | - Yuri N Klimochkin
- Department of Organic Chemistry, Samara State Technical University, Molodogvardeyskaya 244, Samara, 443100, Russia
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Abstract
Viroporins are short polypeptides encoded by viruses. These small membrane proteins assemble into oligomers that can permeabilize cellular lipid bilayers, disrupting the physiology of the host to the advantage of the virus. Consequently, efforts during the last few decades have been focused towards the discovery of viroporin channel inhibitors, but in general these have not been successful to produce licensed drugs. Viroporins are also involved in viral pathogenesis by engaging in critical interactions with viral proteins, or disrupting normal host cellular pathways through coordinated interactions with host proteins. These protein-protein interactions (PPIs) may become alternative attractive drug targets for the development of antivirals. In this sense, while thus far most antiviral molecules have targeted viral proteins, focus is moving towards targeting host proteins that are essential for virus replication. In principle, this largely would overcome the problem of resistance, with the possibility of using repositioned existing drugs. The precise role of these PPIs, their strain- and host- specificities, and the structural determination of the complexes involved, are areas that will keep the fields of virology and structural biology occupied for years to come. In the present review, we provide an update of the efforts in the characterization of the main PPIs for most viroporins, as well as the role of viroporins in these PPIs interactions.
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Affiliation(s)
| | - David Bhella
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
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Scrima R, Piccoli C, Moradpour D, Capitanio N. Targeting Endoplasmic Reticulum and/or Mitochondrial Ca 2+ Fluxes as Therapeutic Strategy for HCV Infection. Front Chem 2018; 6:73. [PMID: 29619366 PMCID: PMC5871704 DOI: 10.3389/fchem.2018.00073] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 03/06/2018] [Indexed: 01/16/2023] Open
Abstract
Chronic hepatitis C is characterized by metabolic disorders and by a microenvironment in the liver dominated by oxidative stress, inflammation and regeneration processes that can in the long term lead to liver cirrhosis and hepatocellular carcinoma. Several lines of evidence suggest that mitochondrial dysfunctions play a central role in these processes. However, how these dysfunctions are induced by the virus and whether they play a role in disease progression and neoplastic transformation remains to be determined. Most in vitro studies performed so far have shown that several of the hepatitis C virus (HCV) proteins also localize to mitochondria, but the consequences of these interactions on mitochondrial functions remain contradictory and need to be confirmed in the context of productively replicating virus and physiologically relevant in vitro and in vivo model systems. In the past decade we have been proposing a temporal sequence of events in the HCV-infected cell whereby the primary alteration is localized at the mitochondria-associated ER membranes and causes release of Ca2+ from the ER, followed by uptake into mitochondria. This ensues successive mitochondrial dysfunction leading to the generation of reactive oxygen and nitrogen species and a progressive metabolic adaptive response consisting in decreased oxidative phosphorylation and enhanced aerobic glycolysis and lipogenesis. Here we resume the major results provided by our group in the context of HCV-mediated alterations of the cellular inter-compartmental calcium flux homeostasis and present new evidence suggesting targeting of ER and/or mitochondrial calcium transporters as a novel therapeutic strategy.
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Affiliation(s)
- Rosella Scrima
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Claudia Piccoli
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Darius Moradpour
- Service of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland
| | - Nazzareno Capitanio
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
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40
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Morozov VA, Lagaye S. Hepatitis C virus: Morphogenesis, infection and therapy. World J Hepatol 2018; 10:186-212. [PMID: 29527256 PMCID: PMC5838439 DOI: 10.4254/wjh.v10.i2.186] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/11/2018] [Accepted: 02/07/2018] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a major cause of liver diseases including liver cirrhosis and hepatocellular carcinoma. Approximately 3% of the world population is infected with HCV. Thus, HCV infection is considered a public healthy challenge. It is worth mentioning, that the HCV prevalence is dependent on the countries with infection rates around 20% in high endemic countries. The review summarizes recent data on HCV molecular biology, the physiopathology of infection (immune-mediated liver damage, liver fibrosis and lipid metabolism), virus diagnostic and treatment. In addition, currently available in vitro, ex vivo and animal models to study the virus life cycle, virus pathogenesis and therapy are described. Understanding of both host and viral factors may in the future lead to creation of new approaches in generation of an efficient therapeutic vaccine.
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Affiliation(s)
- Vladimir Alexei Morozov
- Center for HIV and Retrovirology, Department of Infectious Diseases, Robert Koch Institute, Berlin 13353, Germany
| | - Sylvie Lagaye
- Department of Immunology, Institut Pasteur, INSERM U1223, Paris 75015, France
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41
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Boukadida C, Fritz M, Blumen B, Fogeron ML, Penin F, Martin A. NS2 proteases from hepatitis C virus and related hepaciviruses share composite active sites and previously unrecognized intrinsic proteolytic activities. PLoS Pathog 2018; 14:e1006863. [PMID: 29415072 PMCID: PMC5819835 DOI: 10.1371/journal.ppat.1006863] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 02/20/2018] [Accepted: 01/08/2018] [Indexed: 12/17/2022] Open
Abstract
Over the recent years, several homologues with varying degrees of genetic relatedness to hepatitis C virus (HCV) have been identified in a wide range of mammalian species. HCV infectious life cycle relies on a first critical proteolytic event of its single polyprotein, which is carried out by nonstructural protein 2 (NS2) and allows replicase assembly and genome replication. In this study, we characterized and evaluated the conservation of the proteolytic mode of action and regulatory mechanisms of NS2 across HCV and animal hepaciviruses. We first demonstrated that NS2 from equine, bat, rodent, New and Old World primate hepaciviruses also are cysteine proteases. Using tagged viral protein precursors and catalytic triad mutants, NS2 of equine NPHV and simian GBV-B, which are the most closely and distantly related viruses to HCV, respectively, were shown to function, like HCV NS2 as dimeric proteases with two composite active sites. Consistent with the reported essential role for NS3 N-terminal domain (NS3N) as HCV NS2 protease cofactor via NS3N key hydrophobic surface patch, we showed by gain/loss of function mutagenesis studies that some heterologous hepacivirus NS3N may act as cofactors for HCV NS2 provided that HCV-like hydrophobic residues are conserved. Unprecedently, however, we also observed efficient intrinsic proteolytic activity of NS2 protease in the absence of NS3 moiety in the context of C-terminal tag fusions via flexible linkers both in transiently transfected cells for all hepaciviruses studied and in the context of HCV dicistronic full-length genomes. These findings suggest that NS3N acts as a regulatory rather than essential cofactor for hepacivirus NS2 protease. Overall, unique features of NS2 including enzymatic function as dimers with two composite active sites and additional NS3-independent proteolytic activity are conserved across hepaciviruses regardless of their genetic distances, highlighting their functional significance in hepacivirus life cycle. Despite remarkable progress in the development of therapeutic options, more than 70 million individuals are chronically infected by hepatitis C virus (HCV) worldwide and major challenges in basic and translational research remain. Phylogenetically-related HCV homologues have recently been identified in the wild in several mammalian species, whose host restriction and potential for zoonosis remain largely unknown. We comparatively characterized the functions and properties of nonstructural proteins 2 (NS2) from several animal hepaciviruses and HCV. We demonstrated that NS2 from animal hepaciviruses, like HCV NS2, are cysteine proteases, which function as dimers with two composite active sites to ensure a key proteolytic event of the single viral polyprotein at the NS2/NS3 junction. In addition to the activation of HCV NS2 protease by NS3 N-terminal domain, our data revealed a novel NS3-independent substrate specificity and efficient intrinsic proteolytic activity of NS2. The conservation of its properties and peculiar mode of action among distantly related hepaciviruses supports an important regulatory role for NS2 protein in the life cycle of these viruses. It also strengthens the value of animal, notably rodent hepaciviruses for the development of surrogate, immunocompetent models of HCV infection to address HCV-associated pathogenesis and vaccine strategies.
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Affiliation(s)
- Célia Boukadida
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Paris, France
- CNRS UMR 3569, Paris, France
- Université Paris Diderot–Sorbonne Paris Cité, Paris, France
| | - Matthieu Fritz
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Paris, France
- CNRS UMR 3569, Paris, France
- Université Paris Diderot–Sorbonne Paris Cité, Paris, France
| | - Brigitte Blumen
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Paris, France
- CNRS UMR 3569, Paris, France
- Université Paris Diderot–Sorbonne Paris Cité, Paris, France
| | - Marie-Laure Fogeron
- Institut de Biologie et Chimie des Protéines, Molecular Microbiology and Structural Biochemistry, Labex Ecofect, UMR 5086 CNRS, Université de Lyon, Lyon, France
| | - François Penin
- Institut de Biologie et Chimie des Protéines, Molecular Microbiology and Structural Biochemistry, Labex Ecofect, UMR 5086 CNRS, Université de Lyon, Lyon, France
| | - Annette Martin
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Paris, France
- CNRS UMR 3569, Paris, France
- Université Paris Diderot–Sorbonne Paris Cité, Paris, France
- * E-mail:
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42
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Dahl SL, Kalita MM, Fischer WB. Interaction of antivirals with a heptameric bundle model of the p7 protein of hepatitis C virus. Chem Biol Drug Des 2018; 91:942-950. [DOI: 10.1111/cbdd.13162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 12/01/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Sophie L. Dahl
- Institute of Pharmacy and Molecular Biotechnology; Heidelberg University; Heidelberg Germany
| | - Monoj Mon Kalita
- Institute of Biophotonics and Biophotonics and Molecular Imaging Research Center (BMIRC); School of Biomedical Science and Engineering; National Yang-Ming University; Taipei Taiwan
| | - Wolfgang B. Fischer
- Institute of Biophotonics and Biophotonics and Molecular Imaging Research Center (BMIRC); School of Biomedical Science and Engineering; National Yang-Ming University; Taipei Taiwan
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43
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Denolly S, Mialon C, Bourlet T, Amirache F, Penin F, Lindenbach B, Boson B, Cosset FL. The amino-terminus of the hepatitis C virus (HCV) p7 viroporin and its cleavage from glycoprotein E2-p7 precursor determine specific infectivity and secretion levels of HCV particle types. PLoS Pathog 2017; 13:e1006774. [PMID: 29253880 PMCID: PMC5749900 DOI: 10.1371/journal.ppat.1006774] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 01/02/2018] [Accepted: 11/27/2017] [Indexed: 12/18/2022] Open
Abstract
Viroporins are small transmembrane proteins with ion channel activities modulating properties of intracellular membranes that have diverse proviral functions. Hepatitis C virus (HCV) encodes a viroporin, p7, acting during assembly, envelopment and secretion of viral particles (VP). HCV p7 is released from the viral polyprotein through cleavage at E2-p7 and p7-NS2 junctions by signal peptidase, but also exists as an E2p7 precursor, of poorly defined properties. Here, we found that ectopic p7 expression in HCVcc-infected cells reduced secretion of particle-associated E2 glycoproteins. Using biochemical assays, we show that p7 dose-dependently slows down the ER-to-Golgi traffic, leading to intracellular retention of E2, which suggested that timely E2p7 cleavage and p7 liberation are critical events to control E2 levels. By studying HCV mutants with accelerated E2p7 processing, we demonstrate that E2p7 cleavage controls E2 intracellular expression and secretion levels of nucleocapsid-free subviral particles and infectious virions. In addition, our imaging data reveal that, following p7 liberation, the amino-terminus of p7 is exposed towards the cytosol and coordinates the encounter between NS5A and NS2-based assembly sites loaded with E1E2 glycoproteins, which subsequently leads to nucleocapsid envelopment. We identify punctual mutants at p7 membrane interface that, by abrogating NS2/NS5A interaction, are defective for transmission of infectivity owing to decreased secretion of core and RNA and to increased secretion of non/partially-enveloped particles. Altogether, our results indicate that the retarded E2p7 precursor cleavage is essential to regulate the intracellular and secreted levels of E2 through p7-mediated modulation of the cell secretory pathway and to unmask critical novel assembly functions located at p7 amino-terminus.
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Affiliation(s)
- Solène Denolly
- CIRI–International Center for Infectiology Research, Team EVIR, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Chloé Mialon
- CIRI–International Center for Infectiology Research, Team EVIR, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Thomas Bourlet
- GIMAP, EA 3064, Faculté de Médecine, Université de Saint-Etienne, Univ Lyon, Saint Etienne, France
| | - Fouzia Amirache
- CIRI–International Center for Infectiology Research, Team EVIR, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - François Penin
- IBCP—Institut de Biologie et Chimie des Protéines, MMSB, UMR 5086, CNRS, Univ Lyon, Lyon, France
| | - Brett Lindenbach
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT, United States of America
| | - Bertrand Boson
- CIRI–International Center for Infectiology Research, Team EVIR, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - François-Loïc Cosset
- CIRI–International Center for Infectiology Research, Team EVIR, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, Lyon, France
- * E-mail:
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Ramsey J, Mukhopadhyay S. Disentangling the Frames, the State of Research on the Alphavirus 6K and TF Proteins. Viruses 2017; 9:v9080228. [PMID: 28820485 PMCID: PMC5580485 DOI: 10.3390/v9080228] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 08/03/2017] [Accepted: 08/16/2017] [Indexed: 01/04/2023] Open
Abstract
For 30 years it was thought the alphavirus 6K gene encoded a single 6 kDa protein. However, through a bioinformatics search 10 years ago, it was discovered that there is a frameshifting event and two proteins, 6K and transframe (TF), are translated from the 6K gene. Thus, many functions attributed to the 6K protein needed reevaluation to determine if they properly belong to 6K, TF, or both proteins. In this mini-review, we reevaluate the past research on 6K and put those results in context where there are two proteins, 6K and TF, instead of one. Additionally, we discuss the most cogent outstanding questions for 6K and TF research, including their collective importance in alphavirus budding and their potential importance in disease based on the latest virulence data.
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Affiliation(s)
- Jolene Ramsey
- Department of Biology at Indiana University, Bloomington, IN 47405, USA.
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45
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Patch-Clamp Study of Hepatitis C p7 Channels Reveals Genotype-Specific Sensitivity to Inhibitors. Biophys J 2017; 110:2419-2429. [PMID: 27276260 DOI: 10.1016/j.bpj.2016.04.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 04/14/2016] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C is a major worldwide disease and health hazard, affecting ∼3% of the world population. The p7 protein of hepatitis C virus (HCV) is an intracellular ion channel and pH regulator that is involved in the viral replication cycle. It is targeted by various classical ion channel blockers. Here, we generated p7 constructs corresponding to HCV genotypes 1a, 2a, 3a, and 4a for recombinant expression in HEK293 cells, and studied p7 channels using patch-clamp recording techniques. The pH50 values for recombinant p7 channels were between 6.0 and 6.5, as expected for proton-activated channels, and current-voltage dependence did not show any differences between genotypes. Inhibition of p7-mediated currents by amantadine, however, exhibited significant, genotype-specific variation. The IC50 values of p7-1a and p7-4a were 0.7 ± 0.1 nM and 3.2 ± 1.2 nM, whereas p7-2a and p7-3a had 50- to 1000-fold lower sensitivity, with IC50 values of 2402 ± 334 nM and 344 ± 64 nM, respectively. The IC50 values for rimantadine were low across all genotypes, ranging from 0.7 ± 0.1 nM, 1.6 ± 0.6 nM, and 3.0 ± 0.8 nM for p7-1a, p7-3a, and p7-4a, respectively, to 24 ± 4 nM for p7-2a. Results from patch-clamp recordings agreed well with cellular assays of p7 activity, namely, measurements of intracellular pH and hemadsorption assays, which confirmed the much reduced amantadine sensitivity of genotypes 2a and 3a. Thus, our results establish patch-clamp studies of recombinant viroporins as a valid analytical tool that can provide quantitative information about viroporin channel properties, complementing established techniques.
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46
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Wang J, Bhattacharyya J, Mastria E, Chilkoti A. A quantitative study of the intracellular fate of pH-responsive doxorubicin-polypeptide nanoparticles. J Control Release 2017; 260:100-110. [PMID: 28576641 DOI: 10.1016/j.jconrel.2017.05.032] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/13/2017] [Accepted: 05/26/2017] [Indexed: 11/27/2022]
Abstract
Nanoscale carriers with an acid-labile linker between the carrier and drug are commonly used for drug delivery. However, their efficacy is potentially limited by inefficient linker cleavage, and lysosomal entrapment of drugs. To address these critical issues, we developed a new imaging method that spatially overlays the location of a nanoparticle and the released drug from the nanoparticle, on a map of the local intracellular pH that delineates individual endosomes and lysosomes, and the therapeutic intracellular target of the drug-the nucleus. We used this method to quantitatively map the intracellular fate of micelles of a recombinant polypeptide conjugated with doxorubicin via an acid-labile hydrazone linker as a function of local pH and time within live cells. We found that hydrolysis of the acid-labile linker is incomplete because the pH range of 4-7 in the endosomes and lysosomes does not provide complete cleavage of the drug from the nanoparticle, but that once cleaved, the drug escapes the acidic endo-lysosomal compartment into the cytosol and traffics to its therapeutic destination-the nucleus. This study also demonstrated that unlike free drug, which enters the cytosol directly through the cell membrane and then traffics into the nucleus, the nanoparticle-loaded drug almost exclusively traffics into endosomes and lysosomes upon intracellular uptake, and only reaches the nucleus after acid-triggered drug release in the endo-lysosomes. This methodology provides a better and more quantitative understanding of the intracellular behavior of drug-loaded nanoparticles, and provides insights for the design of the next-generation of nanoscale drug delivery systems.
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Affiliation(s)
- Jing Wang
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Jayanta Bhattacharyya
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Eric Mastria
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States.
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47
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The p7 viroporin of the hepatitis C virus contributes to liver inflammation by stimulating production of Interleukin-1β. Biochim Biophys Acta Mol Basis Dis 2017; 1863:712-720. [DOI: 10.1016/j.bbadis.2016.12.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 12/08/2016] [Accepted: 12/12/2016] [Indexed: 12/12/2022]
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48
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Falcón V, Acosta-Rivero N, González S, Dueñas-Carrera S, Martinez-Donato G, Menéndez I, Garateix R, Silva JA, Acosta E, Kourı J. Ultrastructural and biochemical basis for hepatitis C virus morphogenesis. Virus Genes 2017; 53:151-164. [PMID: 28233195 DOI: 10.1007/s11262-017-1426-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 01/06/2017] [Indexed: 12/16/2022]
Abstract
Chronic infection with HCV is a leading cause of cirrhosis, hepatocellular carcinoma and liver failure. One of the least understood steps in the HCV life cycle is the morphogenesis of new viral particles. HCV infection alters the lipid metabolism and generates a variety of microenvironments in the cell cytoplasm that protect viral proteins and RNA promoting viral replication and assembly. Lipid droplets (LDs) have been proposed to link viral RNA synthesis and virion assembly by physically associating these viral processes. HCV assembly, envelopment, and maturation have been shown to take place at specialized detergent-resistant membranes in the ER, rich in cholesterol and sphingolipids, supporting the synthesis of luminal LDs-containing ApoE. HCV assembly involves a regulated allocation of viral and host factors to viral assembly sites. Then, virus budding takes place through encapsidation of the HCV genome and viral envelopment in the ER. Interaction of ApoE with envelope proteins supports the viral particle acquisition of lipids and maturation. HCV secretion has been suggested to entail the ion channel activity of viral p7, several components of the classical trafficking and autophagy pathways, ESCRT, and exosome-mediated export of viral RNA. Here, we review the most recent advances in virus morphogenesis and the interplay between viral and host factors required for the formation of HCV virions.
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Affiliation(s)
- Viviana Falcón
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba.
| | - Nelson Acosta-Rivero
- National Center for Scientific Research, P.O. Box 6414, 10600, Havana, Cuba. .,Centre for Protein Studies, Faculty of Biology, University of Havana, 10400, Havana, Cuba.
| | | | | | | | - Ivon Menéndez
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba
| | - Rocio Garateix
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba
| | - José A Silva
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba
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49
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Gerold G, Bruening J, Weigel B, Pietschmann T. Protein Interactions during the Flavivirus and Hepacivirus Life Cycle. Mol Cell Proteomics 2017; 16:S75-S91. [PMID: 28077444 DOI: 10.1074/mcp.r116.065649] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/11/2017] [Indexed: 12/28/2022] Open
Abstract
Protein-protein interactions govern biological functions in cells, in the extracellular milieu, and at the border between cells and extracellular space. Viruses are small intracellular parasites and thus rely on protein interactions to produce progeny inside host cells and to spread from cell to cell. Usage of host proteins by viruses can have severe consequences e.g. apoptosis, metabolic disequilibria, or altered cell proliferation and mobility. Understanding protein interactions during virus infection can thus educate us on viral infection and pathogenesis mechanisms. Moreover, it has led to important clinical translations, including the development of new therapeutic and vaccination strategies. Here, we will discuss protein interactions of members of the Flaviviridae family, which are small enveloped RNA viruses. Dengue virus, Zika virus and hepatitis C virus belong to the most prominent human pathogenic Flaviviridae With a genome of roughly ten kilobases encoding only ten viral proteins, Flaviviridae display intricate mechanisms to engage the host cell machinery for their purpose. In this review, we will highlight how dengue virus, hepatitis C virus, Japanese encephalitis virus, tick-borne encephalitis virus, West Nile virus, yellow fever virus, and Zika virus proteins engage host proteins and how this knowledge helps elucidate Flaviviridae infection. We will specifically address the protein composition of the virus particle as well as the protein interactions during virus entry, replication, particle assembly, and release from the host cell. Finally, we will give a perspective on future challenges in Flaviviridae interaction proteomics and why we believe these challenges should be met.
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Affiliation(s)
- Gisa Gerold
- From the Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Janina Bruening
- From the Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Bettina Weigel
- From the Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Thomas Pietschmann
- From the Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
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50
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Abstract
Eukaryotic cells have evolved a myriad of ion channels, transporters, and pumps to maintain and regulate transmembrane ion gradients. As intracellular parasites, viruses also have evolved ion channel proteins, called viroporins, which disrupt normal ionic homeostasis to promote viral replication and pathogenesis. The first viral ion channel (influenza M2 protein) was confirmed only 23 years ago, and since then studies on M2 and many other viroporins have shown they serve critical functions in virus entry, replication, morphogenesis, and immune evasion. As new candidate viroporins and viroporin-mediated functions are being discovered, we review the experimental criteria for viroporin identification and characterization to facilitate consistency within this field of research. Then we review recent studies on how the few Ca(2+)-conducting viroporins exploit host signaling pathways, including store-operated Ca(2+) entry, autophagy, and inflammasome activation. These viroporin-induced aberrant Ca(2+) signals cause pathophysiological changes resulting in diarrhea, vomiting, and proinflammatory diseases, making both the viroporin and host Ca(2+) signaling pathways potential therapeutic targets for antiviral drugs.
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Affiliation(s)
- Joseph M Hyser
- Alkek Center for Metagenomic and Microbiome Research.,Department of Molecular Virology and Microbiology, and
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, and.,Department of Medicine, Baylor College of Medicine, Houston, Texas 77030-3411;
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