EPH receptor A5 is a protein belongs to the ephrin receptor subfamily of the protein-tyrosine kinase family. EPH and EPH-related receptors have been implicated in mediating developmental events, particularly in the nervous system. Receptors in the EPH subfamily typically have a single kinase domain and an extracellular region containing a Cys-rich domain and 2 fibronectin type III repeats. The ephrin receptors are divided into 2 groups based on the similarity of their extracellular domain sequences and their affinities for binding ephrin-A and ephrin-B ligands.Almost exclusively expressed in the nervous system.Unlike most other receptor PTKs, HEK7 has a restricted pattern of expression; Fox et al. (1995) observed 6-kb and 9-kb mRNAs in human brain and weak expression of the 9-kb mRNA in placenta.