LOCATING THE MAJOR GLYCOPROTEIN (PO PROTEIN) IN THE X-RAY PROFILE OF FROG SCIATIC-NERVE MYELIN

Some detailed X-ray profiles have been developed for frog [Rana pipiens] sciatic-nerve myelin in the past 8 yr; 1 of these is interpreted. Much of the myelin protein is located in the extracellular half of the membrane. On the basis of a chemical analysis and other recently published data indicating the sidedness of some myelin proteins, the major glycoprotein (Po protein) is probably inserted into the extracellular half of the myelin bilayer and it extends into the extracellular space. This interpretation is consistent with known physical properties of the Po protein. Other myelin proteins have not been located. Electron densities and average hydrophobicities of some myelin proteins were calculated, and electron densities and scattering powers of some myelin lipids.