| Abstrakt: |
Molecular genetic evidence indicates that there should be three different (Na++ K+)-stimulated ATPase (Na,K-ATPase) α subunit isozymes in the brain where previously only two (“α” and “α(+)”) were resolved as proteins. To detect and identify α1, α2, and α3 isozymes, polypeptides made by cell-free translation (Schneider, J.W., Mercer, R.W., Gilmore-Hebert, M., Utset, M.F., Lai, C., Greene, A., and Benz, E.J., Jr. (1988) Proc. Natl. Acad. Sci. U.S.A.85, 284–288) were analyzed by gel electrophoresis and proteolytic fingerprinting. Synthetic α1 comigrated with tissue α1, while α2 and α3 comigrated with the leading and trailing edges, respectively, of tissue “α(+).” Proteolytic fingerprints of newborn rat brain Na,K-ATPase labeled in vivowith L-[35S]methionine indicated the presence of α1 and α3, and a low level of α2. |
