Formation of secretory vesicles in permeabilized cells: a salt extract from yeast membranes promotes budding of nascent secretory vesicles from the trans-Golgi network of endocrine cells.
The mechanism of secretory-vesicle formation from the trans-Golgi network (TGN) of endocrine cells is poorly understood. To identify cytosolic activities that facilitate the formation and fission of nascent secretory vesicles, we treated permeabilized pituitary GH3 cells with high salt to remove endogenous budding factors. Using this cell preparation, secretory-vesicle budding from the TGN required addition of exogenous cytosol and energy. Mammalian cytosols (GH3 cells and bovine brain) promoted post-TGN vesicle formation. Most significantly, a salt extract of membranes from the yeast Saccharomyces cerevisiae, a cell lacking a regulated secretory pathway, stimulated secretory vesicle budding in the absence of mammalian cytosolic factors. These results demonstrate that the factors which promote secretory-vesicle release from the TGN are conserved between yeast and mammalian cells.
Ling
W L
WL
Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, New York, USA.
Shields
D
D
D000818:Animals; D001921:Brain / Q000502:physiology; D002417:Cattle; D002460:Cell Line; D002462:Cell Membrane; D002463:Cell Membrane Permeability; D003594:Cytoplasmic Granules / Q000187:drug effects / Q000502:physiology*; D003600:Cytosol / Q000502:physiology; D006056:Golgi Apparatus / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008322:Mammals; D010902:Pituitary Gland; D010911:Pituitary Neoplasms; D011498:Protein Precursors / Q000096:biosynthesis; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis; D012441:Saccharomyces cerevisiae; D013004:Somatostatin / Q000096:biosynthesis; D014020:Tissue Extracts / Q000494:pharmacology; D014162:Transfection
D011498:Protein Precursors; D011994:Recombinant Proteins; D014020:Tissue Extracts; D013004:Somatostatin