title: An unrecognized function for COPII components in recruiting the viral replication protein BMV 1a to the perinuclear ER.
abstract: Positive-strand RNA viruses invariably assemble their viral replication complexes (VRCs) by remodeling host intracellular membranes. How viral replication proteins are targeted to specific organelle membranes to initiate VRC assembly remains elusive. Brome mosaic virus (BMV), whose replication can be recapitulated in Saccharomyces cerevisiae, assembles its VRCs by invaginating the outer perinuclear endoplasmic reticulum (ER) membrane. Remarkably, BMV replication protein 1a (BMV 1a) is the only viral protein required for such membrane remodeling. We show that ER-vesicle protein of 14 kD (Erv14), a cargo receptor of coat protein complex II (COPII), interacts with BMV 1a. Moreover, the perinuclear ER localization of BMV 1a is disrupted in cells lacking ERV14 or expressing dysfunctional COPII coat components (Sec13, Sec24 or Sec31). The requirement of Erv14 for the localization of BMV 1a is bypassed by addition of a Sec24-recognizable sorting signal to BMV 1a or by overexpressing Sec24, suggesting a coordinated effort by both Erv14 and Sec24 for the proper localization of BMV 1a. The COPII pathway is well known for being involved in protein secretion; our data suggest that a subset of COPII coat proteins have an unrecognized role in targeting proteins to the perinuclear ER membrane.
authors.affiliation: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Sciences, Rehovot 7610001, Israel.
authors.forename: Shai
authors.initials: S
authors.lastname: Fuchs
authors.affiliation: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Jiantao
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Wellford
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Sciences, Rehovot 7610001, Israel.
authors.forename: Maya
authors.initials: M
authors.lastname: Schuldiner
authors.affiliation: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA 24061, USA reachxw@vt.edu.
authors.forename: Xiaofeng
authors.identifier: 0000-0002-3850-3274
authors.initials: X
authors.lastname: Wang
mesh_terms: D017795:Bromovirus / Q000502:physiology / Q000648:ultrastructure; D022181:COP-Coated Vesicles / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D017353:Gene Deletion; D016679:Genome, Viral; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007425:Intracellular Membranes / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D011485:Protein Binding; D012367:RNA, Viral; D012441:Saccharomyces cerevisiae / Q000378:metabolism / Q000648:ultrastructure / Q000821:virology; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D014764:Viral Proteins / Q000378:metabolism*; D014779:Virus Replication / Q000502:physiology*
chemical_list: C493590:Erv14 protein, S cerevisiae; D008565:Membrane Proteins; D010940:Plant Proteins; D012367:RNA, Viral; D029701:Saccharomyces cerevisiae Proteins; D014764:Viral Proteins; D049452:Green Fluorescent Proteins
keywords: COPII; Erv14; Positive-strand RNA viruses; Protein perinuclear ER localization; Viral replication complexes; Viral replication protein targeting