Mediates homophilic cell-cell adhesion (By similarity). Minor component of the myelin sheath. May be involved in completion and/or maintenance of the myelin sheath and in cell-cell communication. (Microbial infection) Acts as a receptor for rubella virus. Homodimer (By similarity). May form heterodimers between the different isoforms (By similarity). (Microbial infection) Interacts with rubella virus E2 glycoprotein. Additional isoforms seem to exist. Found exclusively in the CNS, where it is localized on the surface of myelin and oligodendrocyte cytoplasmic membranes. The disease is caused by variants affecting the gene represented in this entry. Not functionally active. May be expressed at low level in the adult. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the immunoglobulin superfamily. BTN/MOG family. Do not confuse myelin-oligodendrocyte glycoprotein (MOG) with oligodendrocyte-myelin glycoprotein (OMG). Myelin oligodendrocyte glycoprotein entry