Cargando…

Characteristics of endoplasmic reticulum-derived transport vesicles

We have isolated vesicles that mediate protein transport from the ER to Golgi membranes in perforated yeast. These vesicles, which form de novo during in vitro incubations, carry lumenal and membrane proteins that include core-glycosylated pro-alpha-factor, Bet1, Sec22, and Bos1, but not ER-resident...

Descripción completa

Detalles Bibliográficos
Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1994
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2120166/
https://www.ncbi.nlm.nih.gov/pubmed/8063853
_version_ 1782141431720181760
collection PubMed
description We have isolated vesicles that mediate protein transport from the ER to Golgi membranes in perforated yeast. These vesicles, which form de novo during in vitro incubations, carry lumenal and membrane proteins that include core-glycosylated pro-alpha-factor, Bet1, Sec22, and Bos1, but not ER-resident Kar2 or Sec61 proteins. Thus, lumenal and membrane proteins in the ER are sorted prior to transport vesicle scission. Inhibition of Ypt1p-function, which prevents newly formed vesicles from docking to cis-Golgi membranes, was used to block transport. Vesicles that accumulate are competent for fusion with cis-Golgi membranes, but not with ER membranes, and thus are functionally committed to vectorial transport. A 900-fold enrichment was developed using differential centrifugation and a series of velocity and equilibrium density gradients. Electron microscopic analysis shows a uniform population of 60 nm vesicles that lack peripheral protein coats. Quantitative Western blot analysis indicates that protein markers of cytosol and cellular membranes are depleted throughout the purification, whereas the synaptobrevin-like Bet1, Sec22, and Bos1 proteins are highly enriched. Uncoated ER-derived transport vesicles (ERV) contain twelve major proteins that associate tightly with the membrane. The ERV proteins may represent abundant cargo and additional targeting molecules.
format Text
id pubmed-2120166
institution National Center for Biotechnology Information
language English
publishDate 1994
publisher The Rockefeller University Press
record_format MEDLINE/PubMed
spelling pubmed-21201662008-05-01 Characteristics of endoplasmic reticulum-derived transport vesicles J Cell Biol Articles We have isolated vesicles that mediate protein transport from the ER to Golgi membranes in perforated yeast. These vesicles, which form de novo during in vitro incubations, carry lumenal and membrane proteins that include core-glycosylated pro-alpha-factor, Bet1, Sec22, and Bos1, but not ER-resident Kar2 or Sec61 proteins. Thus, lumenal and membrane proteins in the ER are sorted prior to transport vesicle scission. Inhibition of Ypt1p-function, which prevents newly formed vesicles from docking to cis-Golgi membranes, was used to block transport. Vesicles that accumulate are competent for fusion with cis-Golgi membranes, but not with ER membranes, and thus are functionally committed to vectorial transport. A 900-fold enrichment was developed using differential centrifugation and a series of velocity and equilibrium density gradients. Electron microscopic analysis shows a uniform population of 60 nm vesicles that lack peripheral protein coats. Quantitative Western blot analysis indicates that protein markers of cytosol and cellular membranes are depleted throughout the purification, whereas the synaptobrevin-like Bet1, Sec22, and Bos1 proteins are highly enriched. Uncoated ER-derived transport vesicles (ERV) contain twelve major proteins that associate tightly with the membrane. The ERV proteins may represent abundant cargo and additional targeting molecules. The Rockefeller University Press 1994-09-01 /pmc/articles/PMC2120166/ /pubmed/8063853 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).
spellingShingle Articles
Characteristics of endoplasmic reticulum-derived transport vesicles
title Characteristics of endoplasmic reticulum-derived transport vesicles
title_full Characteristics of endoplasmic reticulum-derived transport vesicles
title_fullStr Characteristics of endoplasmic reticulum-derived transport vesicles
title_full_unstemmed Characteristics of endoplasmic reticulum-derived transport vesicles
title_short Characteristics of endoplasmic reticulum-derived transport vesicles
title_sort characteristics of endoplasmic reticulum-derived transport vesicles
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2120166/
https://www.ncbi.nlm.nih.gov/pubmed/8063853