Cargando…

A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly

Hepatitis C virus (HCV) assembly remains a poorly understood process. Lipid droplets (LDs) are thought to act as platforms for the assembly of viral components. The JFH1 HCV strain replicates and assembles in association with LD-associated membranes, around which viral core protein is predominantly...

Descripción completa

Detalles Bibliográficos
Autores principales: Boson, Bertrand, Granio, Ophélia, Bartenschlager, Ralf, Cosset, François-Loïc
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3141040/
https://www.ncbi.nlm.nih.gov/pubmed/21814513
http://dx.doi.org/10.1371/journal.ppat.1002144
_version_ 1782208618749231104
author Boson, Bertrand
Granio, Ophélia
Bartenschlager, Ralf
Cosset, François-Loïc
author_facet Boson, Bertrand
Granio, Ophélia
Bartenschlager, Ralf
Cosset, François-Loïc
author_sort Boson, Bertrand
collection PubMed
description Hepatitis C virus (HCV) assembly remains a poorly understood process. Lipid droplets (LDs) are thought to act as platforms for the assembly of viral components. The JFH1 HCV strain replicates and assembles in association with LD-associated membranes, around which viral core protein is predominantly detected. In contrast, despite its intrinsic capacity to localize to LDs when expressed individually, we found that the core protein of the high-titer Jc1 recombinant virus was hardly detected on LDs of cell culture-grown HCV (HCVcc)-infected cells, but was mainly localized at endoplasmic reticulum (ER) membranes where it colocalized with the HCV envelope glycoproteins. Furthermore, high-titer cell culture-adapted JFH1 virus, obtained after long-term culture in Huh7.5 cells, exhibited an ER-localized core in contrast to non-adapted JFH1 virus, strengthening the hypothesis that ER localization of core is required for efficient HCV assembly. Our results further indicate that p7 and NS2 are HCV strain-specific factors that govern the recruitment of core protein from LDs to ER assembly sites. Indeed, using expression constructs and HCVcc recombinant genomes, we found that p7 is sufficient to induce core localization at the ER, independently of its ion-channel activity. Importantly, the combined expression of JFH1 or Jc1 p7 and NS2 induced the same differential core subcellular localization detected in JFH1- vs. Jc1-infected cells. Finally, results obtained by expressing p7-NS2 chimeras between either virus type indicated that compatibilities between the p7 and the first NS2 trans-membrane domains is required to induce core-ER localization and assembly of extra- and intra-cellular infectious viral particles. In conclusion, we identified p7 and NS2 as key determinants governing the subcellular localization of HCV core to LDs vs. ER and required for initiation of the early steps of virus assembly.
format Online
Article
Text
id pubmed-3141040
institution National Center for Biotechnology Information
language English
publishDate 2011
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-31410402011-08-03 A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly Boson, Bertrand Granio, Ophélia Bartenschlager, Ralf Cosset, François-Loïc PLoS Pathog Research Article Hepatitis C virus (HCV) assembly remains a poorly understood process. Lipid droplets (LDs) are thought to act as platforms for the assembly of viral components. The JFH1 HCV strain replicates and assembles in association with LD-associated membranes, around which viral core protein is predominantly detected. In contrast, despite its intrinsic capacity to localize to LDs when expressed individually, we found that the core protein of the high-titer Jc1 recombinant virus was hardly detected on LDs of cell culture-grown HCV (HCVcc)-infected cells, but was mainly localized at endoplasmic reticulum (ER) membranes where it colocalized with the HCV envelope glycoproteins. Furthermore, high-titer cell culture-adapted JFH1 virus, obtained after long-term culture in Huh7.5 cells, exhibited an ER-localized core in contrast to non-adapted JFH1 virus, strengthening the hypothesis that ER localization of core is required for efficient HCV assembly. Our results further indicate that p7 and NS2 are HCV strain-specific factors that govern the recruitment of core protein from LDs to ER assembly sites. Indeed, using expression constructs and HCVcc recombinant genomes, we found that p7 is sufficient to induce core localization at the ER, independently of its ion-channel activity. Importantly, the combined expression of JFH1 or Jc1 p7 and NS2 induced the same differential core subcellular localization detected in JFH1- vs. Jc1-infected cells. Finally, results obtained by expressing p7-NS2 chimeras between either virus type indicated that compatibilities between the p7 and the first NS2 trans-membrane domains is required to induce core-ER localization and assembly of extra- and intra-cellular infectious viral particles. In conclusion, we identified p7 and NS2 as key determinants governing the subcellular localization of HCV core to LDs vs. ER and required for initiation of the early steps of virus assembly. Public Library of Science 2011-07-21 /pmc/articles/PMC3141040/ /pubmed/21814513 http://dx.doi.org/10.1371/journal.ppat.1002144 Text en Boson et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Boson, Bertrand
Granio, Ophélia
Bartenschlager, Ralf
Cosset, François-Loïc
A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly
title A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly
title_full A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly
title_fullStr A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly
title_full_unstemmed A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly
title_short A Concerted Action of Hepatitis C Virus P7 and Nonstructural Protein 2 Regulates Core Localization at the Endoplasmic Reticulum and Virus Assembly
title_sort concerted action of hepatitis c virus p7 and nonstructural protein 2 regulates core localization at the endoplasmic reticulum and virus assembly
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3141040/
https://www.ncbi.nlm.nih.gov/pubmed/21814513
http://dx.doi.org/10.1371/journal.ppat.1002144
work_keys_str_mv AT bosonbertrand aconcertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly
AT granioophelia aconcertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly
AT bartenschlagerralf aconcertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly
AT cossetfrancoisloic aconcertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly
AT bosonbertrand concertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly
AT granioophelia concertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly
AT bartenschlagerralf concertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly
AT cossetfrancoisloic concertedactionofhepatitiscvirusp7andnonstructuralprotein2regulatescorelocalizationattheendoplasmicreticulumandvirusassembly