Title: | Immuno-isolation of Sec7p-coated transport vesicles from the yeast secretory pathway |
Author(s): | Franzusoff A; Lauze E; Howell KE; |
Address: | "Department of Cellular and Structural Biology, University of Colorado Medical School, Denver 80262" |
ISSN/ISBN: | 0028-0836 (Print) 0028-0836 (Linking) |
Abstract: | "The transport of proteins destined for post-endoplasmic reticulum locations in the secretory pathway is mediated by small vesicular carriers. Transport vesicles have been generated in cell-free assays from the yeast Saccharomyces cerevisiae, and mammalian systems. Yeast genes encoding cytosolic components that participate in vesicular traffic were first identified from the collection of conditional-lethal sec-(secretory) mutants. Mutations in the yeast SEC7 gene disrupt protein transport in the secretory pathway at the nonpermissive temperature. The SEC7 gene product is a phosphoprotein of relative molecular mass 230,000 that functions from the cytoplasmic aspect of intracellular membranes. We report that in a yeast cell-free transport assay, the introduction of antibodies to Sec7 protein (Sec7p) results in the accumulation of transport vesicles. These vesicles are retrieved with Sec7p-specific antibodies by immuno-isolation for biochemical and electron microscopic characterization. Sec7p on the surface of the accumulated transport vesicles, in combination with previous genetic and biochemical studies, implicate Sec7p as part of a (non-clathrin) vesicle coat. This Sec7p-containing coat structure is proposed to be essential for vesicle budding at multiple stages in the yeast secretory pathway" |
Keywords: | Biological Transport Cell Fractionation Endoplasmic Reticulum/chemistry Fungal Proteins/*analysis/immunology/metabolism Golgi Apparatus/chemistry *Guanine Nucleotide Exchange Factors Immunosorbent Techniques Magnetics Mating Factor Organelles/chemistry/me; |
Notes: | "MedlineFranzusoff, A Lauze, E Howell, K E eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. England 1992/01/09 Nature. 1992 Jan 9; 355(6356):173-5. doi: 10.1038/355173a0" |