EDG-4 belongs to a family of G-protein coupled receptors whose ligands are lysophospholipids. The ligand for EDG-4 is lysophospholipid. There are 6 known members of the EDG receptor family and they are implicated in mediating growthrelated 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. EDG 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. EDG4 is expressed in testes, ovarian tumor and leukocyte containing tissues.