– Mouse Ephrin-B1 is a single-pass type I membrane protein which belongs to the ephrin family. It contains an ephrin RBD (ephrin receptor-binding) domain, and expressed in heart, placenta, lung, liver, skeletal muscle, kidney and pancreas. Ephrin-B1 is cell surface transmembrane ligand for Eph receptors, a family of receptor tyrosine kinases which are crucial for migration, repulsion and adhesion during neuronal, vascular and epithelial development. It binds promiscuously Eph receptors residing on adjacent cells, leading to contact-dependent bidirectional signaling into neighboring cells. It may play a role in cell adhesion and function in the development or maintenance of the nervous system.