Ephrin-B1 (EFNB1) is also known as EFL-3, ELK ligand, EPH-related receptor tyrosine kinase ligand 2 (LERK-2), which belongs to the ephrin family. EFNB1 contains one ephrin RBD (ephrin receptor-binding) domain. EFNB1 binds to the receptor tyrosine kinases EPHB1 and EPHA1. EFNB1 binds to, and induce the collapse of, commissural axons/growth cones in vitro. EFNB1 may play a role in constraining the orientation of longitudinally projecting axons. EFNB1 interacts with GRIP1 and GRIP2.