A comparative study of the polypeptides of mammalian peripheral nerve myelin

Polypeptide components of peripheral nerve myelin prepared from sciatic nerves of mouse, rat, rabbit, cat, guinea pig, monkey, dog and chicken were analyzed using a 20% polyacrylamide slab-gel electrophoresis system. Using this technique, we have demonstrated that there are at least two polypeptides present in the region of P1 protein (mol. wt. 18,000 and 16,000), and two closely moving components in the region of P2 protein (mol. wt. 13,500). A polypeptide (mol. wt. 10,500) is present in significant amounts only in mouse sciatic nerve myelin. Staining with periodic acid-Schiff reagent shows that in addition to P0 protein (mol. wt. 28,000), the major glycoprotein of peripheral nerve myelin, there are several minor glycoprotein components in both the high and low molecular weight regions.