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Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation
The endoplasmic reticulum (ER) mediates the folding, maturation, and deployment of the secretory proteome. Proteins that fail to achieve their native conformation are retained in the ER and targeted for clearance by ER-associated degradation (ERAD), a sophisticated process that mediates the ubiquiti...
Autores principales: | , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
The American Society for Cell Biology
2017
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5231896/ https://www.ncbi.nlm.nih.gov/pubmed/27881664 http://dx.doi.org/10.1091/mbc.E16-07-0483 |
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author | To, Milton Peterson, Clark W. H. Roberts, Melissa A. Counihan, Jessica L. Wu, Tiffany T. Forster, Mercedes S. Nomura, Daniel K. Olzmann, James A. |
author_facet | To, Milton Peterson, Clark W. H. Roberts, Melissa A. Counihan, Jessica L. Wu, Tiffany T. Forster, Mercedes S. Nomura, Daniel K. Olzmann, James A. |
author_sort | To, Milton |
collection | PubMed |
description | The endoplasmic reticulum (ER) mediates the folding, maturation, and deployment of the secretory proteome. Proteins that fail to achieve their native conformation are retained in the ER and targeted for clearance by ER-associated degradation (ERAD), a sophisticated process that mediates the ubiquitin-dependent delivery of substrates to the 26S proteasome for proteolysis. Recent findings indicate that inhibition of long-chain acyl-CoA synthetases with triacsin C, a fatty acid analogue, impairs lipid droplet (LD) biogenesis and ERAD, suggesting a role for LDs in ERAD. However, whether LDs are involved in the ERAD process remains an outstanding question. Using chemical and genetic approaches to disrupt diacylglycerol acyltransferase (DGAT)–dependent LD biogenesis, we provide evidence that LDs are dispensable for ERAD in mammalian cells. Instead, our results suggest that triacsin C causes global alterations in the cellular lipid landscape that disrupt ER proteostasis by interfering with the glycan trimming and dislocation steps of ERAD. Prolonged triacsin C treatment activates both the IRE1 and PERK branches of the unfolded protein response and ultimately leads to IRE1-dependent cell death. These findings identify an intimate relationship between fatty acid metabolism and ER proteostasis that influences cell viability. |
format | Online Article Text |
id | pubmed-5231896 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | The American Society for Cell Biology |
record_format | MEDLINE/PubMed |
spelling | pubmed-52318962017-03-30 Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation To, Milton Peterson, Clark W. H. Roberts, Melissa A. Counihan, Jessica L. Wu, Tiffany T. Forster, Mercedes S. Nomura, Daniel K. Olzmann, James A. Mol Biol Cell Articles The endoplasmic reticulum (ER) mediates the folding, maturation, and deployment of the secretory proteome. Proteins that fail to achieve their native conformation are retained in the ER and targeted for clearance by ER-associated degradation (ERAD), a sophisticated process that mediates the ubiquitin-dependent delivery of substrates to the 26S proteasome for proteolysis. Recent findings indicate that inhibition of long-chain acyl-CoA synthetases with triacsin C, a fatty acid analogue, impairs lipid droplet (LD) biogenesis and ERAD, suggesting a role for LDs in ERAD. However, whether LDs are involved in the ERAD process remains an outstanding question. Using chemical and genetic approaches to disrupt diacylglycerol acyltransferase (DGAT)–dependent LD biogenesis, we provide evidence that LDs are dispensable for ERAD in mammalian cells. Instead, our results suggest that triacsin C causes global alterations in the cellular lipid landscape that disrupt ER proteostasis by interfering with the glycan trimming and dislocation steps of ERAD. Prolonged triacsin C treatment activates both the IRE1 and PERK branches of the unfolded protein response and ultimately leads to IRE1-dependent cell death. These findings identify an intimate relationship between fatty acid metabolism and ER proteostasis that influences cell viability. The American Society for Cell Biology 2017-01-15 /pmc/articles/PMC5231896/ /pubmed/27881664 http://dx.doi.org/10.1091/mbc.E16-07-0483 Text en © 2017 To, Peterson, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). “ASCB®,” “The American Society for Cell Biology®,” and “Molecular Biology of the Cell®” are registered trademarks of The American Society for Cell Biology. |
spellingShingle | Articles To, Milton Peterson, Clark W. H. Roberts, Melissa A. Counihan, Jessica L. Wu, Tiffany T. Forster, Mercedes S. Nomura, Daniel K. Olzmann, James A. Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation |
title | Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation |
title_full | Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation |
title_fullStr | Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation |
title_full_unstemmed | Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation |
title_short | Lipid disequilibrium disrupts ER proteostasis by impairing ERAD substrate glycan trimming and dislocation |
title_sort | lipid disequilibrium disrupts er proteostasis by impairing erad substrate glycan trimming and dislocation |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5231896/ https://www.ncbi.nlm.nih.gov/pubmed/27881664 http://dx.doi.org/10.1091/mbc.E16-07-0483 |
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