Ephrins and EPH-related receptors comprise the largest subfamily of receptor protein-tyrosine kinases. The Eph Receptors characteristically have a single kinase domain and an extracellular region containing a Cys-rich domain and 2 fibronectin type III repeats. Based upon their structures and sequence relationships, ephrins are divided into the ephrin-A (EFNA) class, which are attached to the membrane by a glycosylphosphatidylinositol linkage, and the ephrin-B (EFNB) class, which are transmembrane proteins. Class A ephrins are linked to the membrane by a GPI linkage and bind primarily to EphA receptors, Class B ephrins contain a membrane-spanning region and bind primarily to EphB receptors. Both ephrins and Eph receptors are largely expressed throughout the ectoderm, mesoderm, and endoderm of vertebrate embryos. EFNB3 is a member of the ephrin gene family.EFNB3 is significant in brain development as well as in its maintenance. Furthermore, since levels of EFNB3 expression were particularly high in several forebrain subregions compared to other brain subregions, it may play a key role in forebrain function Synonyms: Ephrin-B3, EPH-related receptor tyrosine kinase ligand 8, LERK-8, EPH-related receptor transmembrane ligand ELK-L3, EFNB3, EPLG8, LERK8, EFL6