Plays a role in myelin formation. Localized mainly in the Schmidt-Lanterman incisures and paranodes of noncompact peripheral nerve myelin. Found in the peripheral nervous system (PNS) Schwann cells (at protein level). Expressed in the PNS, primarily limited to Schwann cells. Expressed in sciatic nerve and placenta at 15.5 dpc. Up-regulated in Schwann cells by EGR2 during nerve development and after nerve injury. Glycosylated.