Sphingosine-1-phosphate is a potent proliferative, survival, and morphogenetic factor, acting
as an extracellular ligand for the EDG family of G-protein-coupled receptors and possibly
intracellularly through as yet, unidentified targets. It is produced within most, if not all cells by
phosphorylation of sphingosine, and is an abundant serum lipid that is released from
activated platelets. Sphingosine and sphingosine-1-phosphate are in dynamic equilibrium
with each other due to the activities of sphingosine kinase and sphingosine-1-phosphate …