Endothelial cell differentation gene-3 (EDG3) belongs to a family of G-protein couple receptors whose ligands are lysophospholipids. The ligand for EDG3 is sphingosine-1-phosphate. There are 8 known members of the EDG receptor family. They have been implicated in mediating growth related effects such as induction of cellular proliferation, alterations in differentiation and survival suppression of apoptosis. They also evoke cellular effector functions that are dependent on cytoskeletal responses such as contraction, secretion, adhesion and chemotaxis. EDG receptors are developmentally regulated and differ in tissue distribution. The couple to multiple types of G proteins to signal through ras and MAP kinase, rho, phospholipase C and several protein tyrosine kinases. EDG3 is expressed in cardiovascular, leukocyte-containing and other tissues.