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Sphingosine-1-phosphate: signaling inside and out
1Department of Biochemistry, Georgetown University Medical Center, 353 Basic Science Building, 3900 Reservoir Road NW, Washington, DC 20007, USA. spiegel@bc.georgetown.edu
FEBS Letters
|July 6, 2000
Summary
Sphingosine-1-phosphate (SPP) acts as an intracellular messenger for cell survival and calcium signaling. It also functions as an extracellular ligand for G-protein-coupled receptors, mediating dual signaling actions.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Pharmacology
Background:
- Sphingosine-1-phosphate (SPP) is recognized as an intracellular second messenger.
- The balance between ceramide and SPP metabolites influences cell survival and death pathways.
- SPP is implicated in regulating calcium mobilization, cell growth, and survival.
Purpose of the Study:
- To elucidate the dual signaling roles of sphingosine-1-phosphate (SPP).
- To highlight SPP's function as both an intracellular messenger and an extracellular ligand.
Main Methods:
- Literature review of existing evidence on SPP signaling.
- Analysis of SPP's role in intracellular pathways.
- Investigation of SPP's interaction with G-protein-coupled receptors.
Main Results:
- SPP regulates intracellular processes including calcium mobilization, cell growth, and survival.
- The balance of sphingolipid metabolites (ceramide and SPP) dictates cell fate.
- SPP is identified as the ligand for the EDG-1 family of G-protein-coupled receptors (EDG-1, -3, -5, -6, -8).
Conclusions:
- Sphingosine-1-phosphate (SPP) exhibits novel dual signaling capabilities, acting both inside and outside the cell.
- SPP's dual action as an intracellular messenger and extracellular mediator is crucial for cellular regulation.
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