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Updated: Aug 12, 2026
10:32
Mitochondria-associated ER Membranes (MAMs) and Glycosphingolipid Enriched Microdomains (GEMs): Isolation from Mouse Brain
Published on: March 4, 2013
Membrane biogenesis and the unfolded protein response
David Ron1, Randolph Y Hampton
1Skirball Institute of Biomolecular Medicine, School of Medicine, New York University, New York, NY 10016, USA. ron@saturn.med.nyu.edu
The Journal of Cell Biology
|October 14, 2004
Summary
The endoplasmic reticulum (ER) controls phospholipid synthesis through a signaling pathway that responds to unfolded protein levels. This finding links protein processing capacity with membrane demand in the ER.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The endoplasmic reticulum (ER) is crucial for protein synthesis and lipid production.
- The ER synthesizes lipids for the endomembrane system.
- A link between protein processing and membrane synthesis in the ER was previously suggested by yeast genetics.
Purpose of the Study:
- To investigate the role of ER unfolded protein response signaling in phospholipid biosynthesis.
- To provide direct evidence for the integration of ER membrane demand with protein processing capacity.
Main Methods:
- The study implicates a signaling pathway involved in the unfolded protein response.
- Genetic analysis in yeast provided initial suggestions.
Main Results:
- A signaling pathway responding to ER unfolded protein load directly influences phospholipid biosynthesis.
- New data support the integration of ER membrane demand with protein processing capacity.
Conclusions:
- The endoplasmic reticulum actively regulates its own membrane synthesis based on protein folding status.
- This regulation suggests mechanistic links between protein homeostasis and lipid metabolism within the ER.
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01:37The Unfolded Protein Response
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