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10:52
Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation
Published on: January 6, 2016
Putting the pH into phosphatidic acid signaling.
John J H Shin1, Christopher J R Loewen
1Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, Canada, V6T 1Z3.
BMC Biology
|December 6, 2011
Summary
Phosphatidic acid (PA) acts as a novel pH biosensor, detecting cellular pH changes to regulate signaling pathways. This pH-sensing ability, due to its headgroup, suggests widespread lipid-based pH detection in biology.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Signaling
Background:
- Phosphatidic acid (PA) is a key lipid involved in cellular signaling and metabolism.
- The precise mechanisms by which PA regulates these processes are under continuous investigation.
Purpose of the Study:
- To explore the novel function of phosphatidic acid (PA) as a pH biosensor.
- To investigate how PA couples pH changes to intracellular signaling.
Main Methods:
- The study focuses on the biophysical and biochemical properties of the PA headgroup.
- Investigated the role of the phosphomonoester moiety in pH sensing.
Main Results:
- New evidence reveals PA functions as an unprecedented pH biosensor.
- PA's phosphomonoester headgroup is responsible for sensing pH.
- This mechanism links cellular pH fluctuations to signaling pathways.
Conclusions:
- Lipid-based pH sensing is a newly identified biological mechanism.
- The pH-sensing property of PA has significant implications for understanding cell signaling.
- Other signaling lipids with phosphomonoester headgroups may also function as pH sensors, indicating a potentially widespread phenomenon.
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