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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...
Formato: | Texto |
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Lenguaje: | English |
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The Rockefeller University Press
1994
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2120166/ https://www.ncbi.nlm.nih.gov/pubmed/8063853 |
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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 |