Oligodendrocyte myelin glycoprotein (OMgp) is a glycosylphosphatidylinositol-anchored protein expressed by neurons and oligodendrocytes in the central nervous system (CNS). It plays a role in inhibiting neurite outgrowth and growth cone collapse through its interaction with the Nogo receptor, NgR. This function is mediated by its leucine-rich repeat domain, which is highly conserved in mammals. OMgp is also implicated in the formation and maintenance of myelin sheaths, and its expression and localization suggest involvement in brain development and regeneration after injury.