Component of Schwann cell signaling pathway(s) that controls axon segregation and myelin formation. Can bind to ADAM11, ADAM22 and ADAM23. Brain. Expressed in the entire developing peripheral nerves. Strongly expressed in the trigeminal nerve and ganglion and particularly abundant in the boundary cap cells - a transient population of cells that contributes to the Schwann cell population of the dorsal root nerve. Expressed at 14 dpc. Defects in Lgi4 are the cause of the claw paw (clp) phenotype. Mice are characterized by limb posture abnormalities and peripheral hypomyelination, with no sign of dysmyelination in the CNS.