Abstract
To study the membrane anchoring of the 120 kDa component of the neural cell adhesion molecule N-CAM, the smallest form lacking a transmembrane domain, cultured mouse neural cells were treated with phosphatidylinositol-specific phospholipase C from
Staphylococcus aureus. When live cultures of astrocytes and neurons are treated with phosphatidylinositol-specific phospholipase C, N-CAM
120 is released into the supernatant. Under these conditions N-CAM
140 and N-CAM
180 are not released. Phospholipase C from
Bacillus cereus or
Clostridium perfringens does not release N-CAM
120. The embryonic form of N-CAM on astrocytes migrating as a broad band between 120 and 180 kDa is also partially released by phosphatidylinositol-specific phospholipase C as a band migrating between 120 and 160 kDa. These observations suggest novel mechanisms in regulation of N-CAM
120 expression on the cell surface and in modulation of N-CAM-mediated cell adhesion.