D-erythro-Sphingosine

D-erythro-Sphingosine is the natural isomer of sphingosine and acts as a potent inhibitor of protein kinase C (IC₅₀=1-3 μM), but does not inhibit protein kinase A or myosin light chain kinase, and activates casein kinase II. This compound has been shown to inhibit calmodulin-dependent enzymes, phosphatidate phosphohydrolase, ATPase, phosphocholine cytidylyltransferase (CTP), and phorbol dibutyrate binding in vitro in human platelets. D-erythro-Sphingosine is active in intact cells and has been identified as an endogenous constituent in HL-60 cells, neutrophils, rat liver, rat brain and mouse tissues.
Other activities of D-erythro-sphingosine include inhibition of phosphatidate phosphohydrolase, Na⁺,K⁺-ATPase, CTP:phosphocholine cytidylyltransferase, calmodulin-dependent enzymes, binding of factor VII to tissue factor, binding of thyrotropin releasing hormone to its receptor and activation of EGF receptor kinase, phospholipase D and casein kinase II.