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Quantitative Analysis of the Cellular Lipidome of Saccharomyces Cerevisiae Using Liquid Chromatography Coupled with Tandem Mass Spectrometry
Published on: March 8, 2020
Sphingolipids regulate the yeast high-osmolarity glycerol response pathway
Mirai Tanigawa1, Akio Kihara, Minoru Terashima
1Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo, Japan.
Molecular and Cellular Biology
|May 16, 2012
Summary
Inhibition of sphingolipid synthesis activates the yeast high-osmolarity glycerol (HOG) pathway. This reveals sphingolipid regulation of osmosensing machinery in yeast cell membranes.
Area of Science:
- Cellular biology
- Molecular biology
- Biochemistry
Background:
- The yeast high-osmolarity glycerol (HOG) pathway regulates cellular response to osmotic stress.
- Two branches, Sln1 and Sho1, mediate osmosensing, but sensing mechanisms are unclear.
Purpose of the Study:
- To elucidate the mechanism of hyperosmotic stress sensing by the yeast HOG pathway.
- To investigate the role of sphingolipids and sterols in HOG pathway activation.
Main Methods:
- Inhibition of de novo sphingolipid and ergosterol biosynthesis pathways.
- Analysis of HOG pathway activation via Sln1 and Sho1 branches.
- Biochemical fractionation to isolate detergent-resistant membranes (DRMs).
- Assessing protein complex dissociation and association with DRMs.
Main Results:
- Inhibition of sphingolipid synthesis activates the HOG pathway through both Sln1 and Sho1 branches.
- Ergosterol biosynthesis inhibition also triggers HOG pathway activation.
- Sphingolipids and sterols form membrane rafts, influencing Sln1 and Sho1 localization.
- Sphingolipid depletion and osmotic stress induce similar changes in Sln1 and Sho1 association with DRMs.
Conclusions:
- Sphingolipids play a critical role in regulating the osmosensing machinery of the yeast HOG pathway.
- Membrane raft integrity is essential for proper HOG pathway osmosensing.
- Findings reveal a novel mechanism of osmotic stress response regulation in yeast.
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