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Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes
Published on: October 15, 2016
Sphingosine-1-phosphate: an enigmatic signalling lipid
Sarah Spiegel1, Sheldon Milstien
1Department of Biochemistry, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, Virginia 23298-0614, USA. sspiegel@vcu..edu
Nature Reviews. Molecular Cell Biology
|May 3, 2003
Summary
Sphingosine-1-phosphate (S1P), a vital metabolite, regulates key cellular processes across species. Its receptors control crucial functions like blood vessel formation and immune responses in higher organisms.
Area of Science:
- Biochemistry and Molecular Biology
- Cellular Signaling
- Physiology
Background:
- Sphingolipid metabolism yields bioactive molecules like sphingosine-1-phosphate (S1P).
- S1P exhibits conserved functions across diverse organisms, including yeast, plants, and mammals.
- In higher eukaryotes, S1P acts as a ligand for a family of five G-protein-coupled receptors (S1PRs).
Purpose of the Study:
- To elucidate the functional significance of sphingosine-1-phosphate (S1P) signaling.
- To highlight the roles of S1P receptors (S1PRs) in higher eukaryotes.
- To understand S1P's involvement in critical physiological processes.
Main Methods:
- Comparative analysis of S1P functions across species.
- Investigation of S1P receptor expression and coupling.
- Functional assays to determine S1P-mediated cellular responses.
Main Results:
- Sphingosine-1-phosphate (S1P) demonstrates evolutionarily conserved biological activities.
- S1P receptors are differentially expressed and signal through various G proteins.
- S1P signaling regulates angiogenesis, vascular maturation, cardiac development, immunity, and cell migration.
Conclusions:
- Sphingosine-1-phosphate (S1P) is a crucial signaling molecule with diverse physiological roles.
- S1P receptors are key mediators of complex biological processes in higher eukaryotes.
- S1P signaling pathways are essential for development, vascular homeostasis, and immune function.
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