title: A GRASP55-rab2 effector complex linking Golgi structure to membrane traffic.
abstract: Membrane traffic between the endoplasmic reticulum (ER) and Golgi apparatus and through the Golgi apparatus is a highly regulated process controlled by members of the rab GTPase family. The GTP form of rab1 regulates ER to Golgi transport by interaction with the vesicle tethering factor p115 and the cis-Golgi matrix protein GM130, also part of a complex with GRASP65 important for the organization of cis-Golgi cisternae. Here, we find that a novel coiled-coil protein golgin-45 interacts with the medial-Golgi matrix protein GRASP55 and the GTP form of rab2 but not other Golgi rab proteins. Depletion of golgin-45 disrupts the Golgi apparatus and causes a block in secretory protein transport. These results demonstrate that GRASP55 and golgin-45 form a rab2 effector complex on medial-Golgi essential for normal protein transport and Golgi structure.
authors.affiliation: Department of Cell Biology, Max-Planck-Institute of Biochemistry, Martinsried D-82152, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Short
authors.forename: C
authors.initials: C
authors.lastname: Preisinger
authors.forename: R
authors.initials: R
authors.lastname: Körner
authors.forename: R
authors.initials: R
authors.lastname: Kopajtich
authors.forename: O
authors.initials: O
authors.lastname: Byron
authors.forename: F A
authors.initials: FA
authors.lastname: Barr
mesh_terms: D000818:Animals; D001324:Autoantigens; D006056:Golgi Apparatus / Q000737:chemistry / Q000201:enzymology* / Q000648:ultrastructure; D000077614:Golgi Matrix Proteins; D006367:HeLa Cells; D006801:Humans; D007668:Kidney / Q000166:cytology; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D021381:Protein Transport / Q000502:physiology*; D051381:Rats; D020798:Two-Hybrid System Techniques; D015003:Yeasts; D020693:rab2 GTP-Binding Protein / Q000032:analysis / Q000378:metabolism*
chemical_list: D001324:Autoantigens; C108705:GORASP1 protein, human; C122048:GORASP2 protein, human; D000077614:Golgi Matrix Proteins; C097741:Golgin subfamily A member 2; C491577:Gorasp1 protein, rat; D008565:Membrane Proteins; D020693:rab2 GTP-Binding Protein