title: Golgi cisternal unstacking stimulates COPI vesicle budding and protein transport.
abstract: The Golgi apparatus in mammalian cells is composed of flattened cisternae that are densely packed to form stacks. We have used the Golgi stacking protein GRASP65 as a tool to modify the stacking state of Golgi cisternae. We established an assay to measure protein transport to the cell surface in post-mitotic cells in which the Golgi was unstacked. Cells with an unstacked Golgi showed a higher transport rate compared to cells with stacked Golgi membranes. Vesicle budding from unstacked cisternae in vitro was significantly increased compared to stacked membranes. These results suggest that Golgi cisternal stacking can directly regulate vesicle formation and thus the rate of protein transport through the Golgi. The results further suggest that at the onset of mitosis, unstacking of cisternae allows extensive and rapid vesiculation of the Golgi in preparation for its subsequent partitioning.
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Yanzhuang
authors.initials: Y
authors.lastname: Wang
authors.forename: Jen-Hsuan
authors.initials: JH
authors.lastname: Wei
authors.forename: Blaine
authors.initials: B
authors.lastname: Bisel
authors.forename: Danming
authors.initials: D
authors.lastname: Tang
authors.forename: Joachim
authors.initials: J
authors.lastname: Seemann
mesh_terms: D022181:COP-Coated Vesicles / Q000378:metabolism*; D020755:Coat Protein Complex I; D006056:Golgi Apparatus / Q000378:metabolism / Q000648:ultrastructure*; D000077614:Golgi Matrix Proteins; D006801:Humans; D008565:Membrane Proteins; D008938:Mitosis; D021381:Protein Transport
chemical_list: D020755:Coat Protein Complex I; C108705:GORASP1 protein, human; D000077614:Golgi Matrix Proteins; D008565:Membrane Proteins