Cell migration is influenced by chemodirectants including a large family of receptor tyrosine kinases collectively referred to as Ephs. Ephs are divided into two classes based on their extracellular structure and ligand specificity. Eph receptors that bind preferentially to ephrin-A ligands are referred to as EphA. All Eph receptors contain an extracellular region consisting of a globular domain, a cysteine-rich domain, and two fibronectin type III domains. This is followed by the transmembrane region and cytoplasmic region. The cytoplasmic region contains a juxtamembrane motif with two tyrosine residues, a kinase domain, and a conserved sterile alpha motif (SAM) in the carboxy tail with one conserved tyrosine residue.