The EphA1 protein is a receptor tyrosine kinase that promiscuously binds to ephrin-A ligands on neighboring cells, initiating contact-dependent bidirectional signaling. The forward signal originates from the receptor and the reverse signal originates from the ephrin ligand. EphA1 Protein, Human (HEK293, His) is the recombinant human-derived EphA1 protein, expressed by HEK293 , with C-6*His labeled tag.