Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response.
The protein folding capacity of the endoplasmic reticulum (ER) is regulated by the unfolded protein response (UPR). The UPR senses unfolded proteins in the ER lumen and transmits that information to the cell nucleus, where it drives a transcriptional program that is tailored to re-establish homeosta...
Main Authors: | , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Public Library of Science (PLoS)
2006-11-01
|
Series: | PLoS Biology |
Online Access: | http://europepmc.org/articles/PMC1661684?pdf=render |
id |
doaj-3a241f79ed05421e93655c65f62bc30a |
---|---|
record_format |
Article |
spelling |
doaj-3a241f79ed05421e93655c65f62bc30a2021-07-02T08:04:48ZengPublic Library of Science (PLoS)PLoS Biology1544-91731545-78852006-11-01412e42310.1371/journal.pbio.0040423Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response.Sebastián BernalesKent L McDonaldPeter WalterThe protein folding capacity of the endoplasmic reticulum (ER) is regulated by the unfolded protein response (UPR). The UPR senses unfolded proteins in the ER lumen and transmits that information to the cell nucleus, where it drives a transcriptional program that is tailored to re-establish homeostasis. Using thin section electron microscopy, we found that yeast cells expand their ER volume at least 5-fold under UPR-inducing conditions. Surprisingly, we discovered that ER proliferation is accompanied by the formation of autophagosome-like structures that are densely and selectively packed with membrane stacks derived from the UPR-expanded ER. In analogy to pexophagy and mitophagy, which are autophagic processes that selectively sequester and degrade peroxisomes and mitochondria, the ER-specific autophagic process described utilizes several autophagy genes: they are induced by the UPR and are essential for the survival of cells subjected to severe ER stress. Intriguingly, cell survival does not require vacuolar proteases, indicating that ER sequestration into autophagosome-like structures, rather than their degradation, is the important step. Selective ER sequestration may help cells to maintain a new steady-state level of ER abundance even in the face of continuously accumulating unfolded proteins.http://europepmc.org/articles/PMC1661684?pdf=render |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Sebastián Bernales Kent L McDonald Peter Walter |
spellingShingle |
Sebastián Bernales Kent L McDonald Peter Walter Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response. PLoS Biology |
author_facet |
Sebastián Bernales Kent L McDonald Peter Walter |
author_sort |
Sebastián Bernales |
title |
Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response. |
title_short |
Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response. |
title_full |
Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response. |
title_fullStr |
Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response. |
title_full_unstemmed |
Autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response. |
title_sort |
autophagy counterbalances endoplasmic reticulum expansion during the unfolded protein response. |
publisher |
Public Library of Science (PLoS) |
series |
PLoS Biology |
issn |
1544-9173 1545-7885 |
publishDate |
2006-11-01 |
description |
The protein folding capacity of the endoplasmic reticulum (ER) is regulated by the unfolded protein response (UPR). The UPR senses unfolded proteins in the ER lumen and transmits that information to the cell nucleus, where it drives a transcriptional program that is tailored to re-establish homeostasis. Using thin section electron microscopy, we found that yeast cells expand their ER volume at least 5-fold under UPR-inducing conditions. Surprisingly, we discovered that ER proliferation is accompanied by the formation of autophagosome-like structures that are densely and selectively packed with membrane stacks derived from the UPR-expanded ER. In analogy to pexophagy and mitophagy, which are autophagic processes that selectively sequester and degrade peroxisomes and mitochondria, the ER-specific autophagic process described utilizes several autophagy genes: they are induced by the UPR and are essential for the survival of cells subjected to severe ER stress. Intriguingly, cell survival does not require vacuolar proteases, indicating that ER sequestration into autophagosome-like structures, rather than their degradation, is the important step. Selective ER sequestration may help cells to maintain a new steady-state level of ER abundance even in the face of continuously accumulating unfolded proteins. |
url |
http://europepmc.org/articles/PMC1661684?pdf=render |
work_keys_str_mv |
AT sebastianbernales autophagycounterbalancesendoplasmicreticulumexpansionduringtheunfoldedproteinresponse AT kentlmcdonald autophagycounterbalancesendoplasmicreticulumexpansionduringtheunfoldedproteinresponse AT peterwalter autophagycounterbalancesendoplasmicreticulumexpansionduringtheunfoldedproteinresponse |
_version_ |
1721335091293061120 |