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PubMed · 8252615

Stepwise assembly of functionally active transport vesicles.

J Ostermann·L Orci·K Tani·M Amherdt·M Ravazzola·Z Elazar·J E Rothman
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Abstract

Budding of COP-coated vesicles (the likely carriers of newly synthesized proteins from the endoplasmic reticulum through the Golgi stack) from Golgi cisternae requires ADP-ribosylation factor (ARF), coatomer proteins from the cytosol, GTP, and fatty acyl-coenzyme A (CoA). The assembly of coated buds on the membranes requires coatomer, ARF, and GTP. When palmitoyl-CoA is added, membrane fission occurs at the coated bud, releasing coated vesicles. We show that COP-coated vesicles can be generated stepwise in vitro and isolated in a functionally active form, demonstrating that the minimal set of cytosolic components required for their formation as well as principal steps in their assembly have been identified.

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ADP-Ribosylation FactorsAcyl Coenzyme AAnimalsBiological Transport, ActiveCHO CellsCell CompartmentationCoatomer ProteinCricetinaeGTP-Binding ProteinsGolgi ApparatusGuanosine TriphosphateIn Vitro TechniquesIntracellular MembranesMembrane GlycoproteinsMembrane ProteinsMicrotubule-Associated ProteinsMorphogenesisOrganellesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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J Ostermann, L Orci, K Tani, M Amherdt, M Ravazzola, Z Elazar, J E Rothman. 1993-12-03. Stepwise assembly of functionally active transport vesicles.. https://doi.org/10.1016/0092-8674(93)90545-2

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