title: The ArfGAP Glo3 is required for the generation of COPI vesicles.
abstract: The small GTPase Arf and coatomer (COPI) are required for the generation of retrograde transport vesicles. Arf activity is regulated by guanine exchange factors (ArfGEF) and GTPase-activating proteins (ArfGAPs). The ArfGAPs Gcs1 and Glo3 provide essential overlapping function for retrograde vesicular transport from the Golgi to the endoplasmic reticulum. We have identified Glo3 as a component of COPI vesicles. Furthermore, we find that a mutant version of the Glo3 protein exerts a negative effect on retrograde transport, even in the presence of the ArfGAP Gcs1. Finally, we present evidence supporting a role for ArfGAP protein in the generation of COPI retrograde transport vesicles.
authors.affiliation: Departments of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada B3H 1X5.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Lewis
authors.forename: Pak Phi
authors.initials: PP
authors.lastname: Poon
authors.forename: Richard A
authors.initials: RA
authors.lastname: Singer
authors.forename: Gerald C
authors.initials: GC
authors.lastname: Johnston
authors.forename: Anne
authors.initials: A
authors.lastname: Spang
mesh_terms: D020727:ADP-Ribosylation Factors / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001693:Biological Transport, Active; D022181:COP-Coated Vesicles / Q000378:metabolism*; D004271:DNA, Fungal / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D005800:Genes, Fungal; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008854:Microscopy, Electron; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D033921:Vesicular Transport Proteins
chemical_list: D004271:DNA, Fungal; D004268:DNA-Binding Proteins; C096914:EMP47 protein, S cerevisiae; C089147:GCS1 protein, S cerevisiae; D020690:GTPase-Activating Proteins; D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; D020727:ADP-Ribosylation Factors