Extracts of subcellular fractions isolated from rat brain homogenates were obtained by treatment of the lyophilized preparations with 0.1 N HCl. When the extracts were analyzed by polyacrylamide gel electrophoresis, the only ones found to contain significant amounts of highly basic proteins were those of myelin and nuclei. The electrophoretic patterns of highly basic proteins from nuclei resemb...

Myelin Basic Protein, one of the major membrane protein component of the central nervous system, was used to probe the molecular mechanism of cellular activation by phytohaemagglutinin. Pre-treatment of human lymphocytes with myelin basic protein results in a lower rising of cytosolic concentration of free calcium after stimulation with phytohaemagglutinin. This effect is dependent on myelin ba...

Fractions containing myelin of varying degrees of compaction were prepared from human white matter. Protein kinase activity in these fractions was measured by using both endogenous and exogenous myelin basic protein (MBP) as substrates. In both cases, less compact myelin fractions possessed higher levels of protein kinase activity than the compact myelin fraction. In addition, the specific acti...

A relatively simple preparation of guinea pig brain myelin, free of gross contamination by other cellular elements has been described. Electron microscopic evidence of the predominance of membranous (lamellar) forms was used as the criterion of purity of this fraction. The slight mitochondrial contamination of the myelin fraction was confirmed by its low succinic dehydrogenase activity. Quantit...

Organ-specific highly basic protein derived from guinea pig central nervous system myelin was found to be electrophoretically heterogeneous. It did not appear to be heterogeneous with respect to molecular size. The electrophoretic technique used to demonstrate this heterogeneity was capable of resolving mixtures of closely related basic proteins whether they were present in crude extracts or in...