title: Mobility of the hepatitis C virus NS4B protein on the endoplasmic reticulum membrane and membrane-associated foci.
abstract: The hepatitis C virus (HCV) non-structural protein NS4B induces morphological changes in the endoplasmic reticulum (ER) membrane that may have a direct role in viral RNA replication. A chimeric GFP-NS4B fusion protein located to the ER membrane and to foci that were attached to the ER. These membrane-associated foci (MAFs) could be related to the membrane alterations observed in cells that replicate HCV RNA. The relationship of MAFs to pre-existing cellular structures is not known. Indirect immunofluorescence analysis demonstrated that they did not contain a cellular marker for vesicles, which have been implicated in the replication of other viruses. From photobleaching studies to examine diffusion of NS4B, the GFP-tagged protein had reduced mobility on MAFs compared with on the ER membrane. This slower mobility suggested that NS4B is likely to form different interactions on MAFs and the ER.
authors.affiliation: MRC Virology Unit, Institute of Virology, Church Street, Glasgow G11 5JR, UK.
authors.forename: Sarah N
authors.initials: SN
authors.lastname: Gretton
authors.affiliation: MRC Virology Unit, Institute of Virology, Church Street, Glasgow G11 5JR, UK.
authors.forename: Annette I
authors.initials: AI
authors.lastname: Taylor
authors.affiliation: MRC Virology Unit, Institute of Virology, Church Street, Glasgow G11 5JR, UK.
authors.forename: John
authors.initials: J
authors.lastname: McLauchlan
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D006224:Cricetinae; D022162:Cytoplasmic Vesicles / Q000737:chemistry; D004721:Endoplasmic Reticulum / Q000737:chemistry / Q000821:virology*; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000032:analysis; D016174:Hepacivirus / Q000502:physiology*; D006801:Humans; D018613:Microscopy, Confocal; D012367:RNA, Viral / Q000032:analysis / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000032:analysis; D017361:Viral Nonstructural Proteins / Q000378:metabolism*; D014779:Virus Replication
chemical_list: C093542:NS4 protein, hepatitis C virus; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins; D017361:Viral Nonstructural Proteins; D049452:Green Fluorescent Proteins