Ephrin-A5 is a glycosylphosphatidylinositol (GPI)-anchored protein of the ephrin-A subclass of ephrin ligands that binds to the EphA subclass of Eph receptors. Ephrin-A5 has also been shown to bind to the EphB2 receptor. It is crucial for migration, repulsion and adhesion during neuronal, vascular and epithelial development. Ephrin-A5 binds promiscuously Eph receptors residing on adjacent cells, leading to contact-dependent bidirectional signaling into neighboring cells. The signaling pathway downstream of the receptor is referred to as forward signaling while the signaling pathway downstream of the ephrin ligand is referred to as reverse signaling.