title: Coordinated regulation of bidirectional COPI transport at the Golgi by CDC42.
abstract: The Golgi complex has a central role in the intracellular sorting of secretory proteins. Anterograde transport through the Golgi has been explained by the movement of Golgi cisternae, known as cisternal maturation. Because this explanation is now appreciated to be incomplete, interest has developed in understanding tubules that connect the Golgi cisternae. Here we show that the coat protein I (COPI) complex sorts anterograde cargoes into these tubules in human cells. Moreover, the small GTPase CDC42 regulates bidirectional Golgi transport by targeting the dual functions of COPI in cargo sorting and carrier formation. CDC42 also directly imparts membrane curvature to promote COPI tubule formation. Our findings further reveal that COPI tubular transport complements cisternal maturation in explaining how anterograde Golgi transport is achieved, and that bidirectional COPI transport is modulated by environmental cues through CDC42.
authors.affiliation: 1] Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA [2] Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Seung-Yeol
authors.initials: SY
authors.lastname: Park
authors.affiliation: 1] Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA [2] Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Jia-Shu
authors.initials: JS
authors.lastname: Yang
authors.affiliation: 1] Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA [2] Nephrology Division and Department of Medicine, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA.
authors.forename: Angela B
authors.initials: AB
authors.lastname: Schmider
authors.affiliation: 1] Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA [2] Nephrology Division and Department of Medicine, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA [3] Molecular Imaging Core, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA.
authors.forename: Roy J
authors.initials: RJ
authors.lastname: Soberman
authors.affiliation: 1] Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA [2] Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Victor W
authors.initials: VW
authors.lastname: Hsu
mesh_terms: D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D020755:Coat Protein Complex I / Q000378:metabolism*; D020756:Coatomer Protein / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism; D021381:Protein Transport; D011973:Receptors, LDL / Q000378:metabolism; D014759:Viral Envelope Proteins / Q000378:metabolism; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism*
chemical_list: D020755:Coat Protein Complex I; D020756:Coatomer Protein; C028391:G protein, vesicular stomatitis virus; D008562:Membrane Glycoproteins; D011973:Receptors, LDL; D014759:Viral Envelope Proteins; D020764:cdc42 GTP-Binding Protein