MYELIN OLIGODENDROCYTE-SPECIFIC PROTEIN - A NOVEL SURFACE-MEMBRANE PROTEIN THAT ASSOCIATES WITH MICROTUBULES

Only a few proteins are known to be exclusively expressed in central nervous system (CNS) myelin. A novel surface membrane protein expressed only in CNS myelin and oligodendrocytes of higher vertebrates has been identified by a monoclonal antibody. This CNS myelin/oligodendrocyte-specific protein, MOSP, has a molecular weight of 48 kDa and a pI of approximately 6.7. In the presence of the monoclonal antibody, MOSP remains on the surface of cultured oligodendrocytes but becomes associated with cytoplasmic microtubules. Our results suggest that MOSP plays an important role in membrane/cytoskeleton interactions during the formation and maintenance of CNS myelin. MOSP also may play a critical role in the pathogenesis of diseases of CNS myelin.