Scientific Background: | S1P belongs to a family of G protein-coupled receptors whose ligands are lysophospholipids. There are 8 known members of the lysophospholipid receptor (EDG) family and they are implicated in mediating growth related effects such as induction of cellular proliferation, alterations in differentiation and survival and suppression of apoptosis. They also evoke cellular effector functions that are dependent on cytoskeletal responses such as contraction, secretion, adhesion and chemotaxis. The ligand for S1P is sphingosine-1-phosphate. Lysophospholipid receptors are developmentally regulated and differ in tissue distribution. They couple to multiple types of G proteins to signal through ras and MAP kinase, rho, phospholipase C and several protein tyrosine kinases. S1P is expressed in cardiovascular, leukocyte containing and other tissues. |