MYELIN PROTEIN ZERO AND MEMBRANE ADHESION

Protein zero (P-0) is a member of the immunoglobulin gene superfamily (IgCAM) that is expressed at high levels in myelinated vertebrates in central (fish and amphibia) and peripheral (all species) myelin, This glycoprotein is the major adhesive component of peripheral myelin, whe re it mediates self-adhesion of the Schwann cell plasma membrane. Alth ough the expression of P-0 is naturally limited to Schwann cells, the molecular mechanisms of P-0-mediated adhesion can be considered genera l and ''obligatory'' because, when expressed in a variety of cell line s, P-0 induces strong intercellular adhesion. Modeling studies, X-ray crystallographic analysis, and experimental site-directed mutagenesis have provided excellent working models for understanding how P-0 media tes adhesion at the atomic level. These models remain to be experiment ally tested. However, in humans, certain mutations in P-0 produce dysm yelinating disease, possibly due to disruptions in the predicted P-0 l attice. J. Neurosci, Res. 54:137-146, 1998. (C) 1998 Wiley-Liss, Inc.