Sphingosine
Sphingosine is an 18-carbon amino alcohol with an unsaturated hydrocarbon chain, which forms a primary part of sphingolipids, a class of cell membrane lipids that include sphingomyelin, an important phospholipid.
Functions
Sphingosine can be phosphorylated in vivo via two kinases, sphingosine kinase type 1 and sphingosine kinase type 2. This leads to the formation of sphingosine-1-phosphate, a potent signaling lipid.Sphingolipid metabolites, such as ceramides, sphingosine and sphingosine-1-phosphate, are lipid signaling molecules involved in diverse cellular processes.
Biosynthesis
Sphingosine is synthesized from palmitoyl CoA and serine in a condensation required to yield sphinganine.[Image:Sphingosine synthesis corrected.png|800px|Sphingosine synthesis]
Dehydrosphingosine is then reduced by NADPH to sphinganine, acylated to dihydroceramide, and finally oxidized by FAD to ceramide. Sphingosine is then solely formed via degradation of sphingolipid in the lysosome.