title: Live imaging of yeast Golgi cisternal maturation.
abstract: There is a debate over how protein trafficking is performed through the Golgi apparatus. In the secretory pathway, secretory proteins that are synthesized in the endoplasmic reticulum enter the early compartment of the Golgi apparatus called cis cisternae, undergo various modifications and processing, and then leave for the plasma membrane from the late (trans) cisternae. The cargo proteins must traverse the Golgi apparatus in the cis-to-trans direction. Two typical models propose either vesicular transport or cisternal progression and maturation for this process. The vesicular transport model predicts that Golgi cisternae are distinct stable compartments connected by vesicular traffic, whereas the cisternal maturation model predicts that cisternae are transient structures that form de novo, mature from cis to trans, and then dissipate. Technical progress in live-cell imaging has long been awaited to address this problem. Here we show, by the use of high-speed three-dimensional confocal microscopy, that yeast Golgi cisternae do change the distribution of resident membrane proteins from the cis nature to the trans over time, as proposed by the maturation model, in a very dynamic way.
authors.affiliation: Molecular Membrane Biology Laboratory, RIKEN Discovery Research Institute, Wako, Saitama 351-0198, Japan.
authors.forename: Kumi
authors.initials: K
authors.lastname: Matsuura-Tokita
authors.forename: Masaki
authors.initials: M
authors.lastname: Takeuchi
authors.forename: Akira
authors.initials: A
authors.lastname: Ichihara
authors.forename: Kenta
authors.initials: K
authors.lastname: Mikuriya
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nakano
mesh_terms: D022181:COP-Coated Vesicles / Q000378:metabolism; D020756:Coatomer Protein / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism / Q000502:physiology*; D007425:Intracellular Membranes / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D009154:Mutation; D050766:Qb-SNARE Proteins / Q000378:metabolism; D050600:SNARE Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D033921:Vesicular Transport Proteins
chemical_list: D020756:Coatomer Protein; D005656:Fungal Proteins; C490973:GOS1 protein, S cerevisiae; D008565:Membrane Proteins; D050766:Qb-SNARE Proteins; C089137:RER1 protein, S cerevisiae; D050600:SNARE Proteins; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins