Abstract Brain slices were prepared from 17‐day old rats, and incubated with [ 3 H]glycine or [ 3 H]‐leucine to label proteins. Myelin was isolated from the slices, and the proteins were separated by discontinuous gel electrophoresis in buffers containing sodium dodecyl sulfate. Radioactive basic and Wolfgram proteins appeared in myelin at similar initial rates, and their entry was nearly linear between 15 and 120 min with no detectable lag. Radioactive proteolipid protein appeared in myelin at one‐fourth the rate of the basic and Wolfgram proteins between 0 and 30 min, then entered at a rate comparable to the other proteins between 45 and 120 min. When cycloheximide (0.2 mM) or puromycin (1.0 mM) was added, appearance of newly labeled basic and Wolfgram proteins in myelin stopped while proteolipid protein continued to appear in myelin at a normal rate for at least 30 min. Chase experiments with unlabeled glycine had similar effects. These results indicate the existence of a previously synthesized precursor pool of proteolipid protein with a 30‐min interval between synthesis of proteolipid protein and its appearance in myelin. Incorporation of [ 3 H]fucose into glycoprotein of the myelin sheath was studied, as was inhibition of incorporation of radioactivity by the use of either cycloheximide, or dilution with unlabeled fucose. The results indicated fucosylation of a sizable pool of presynthesized protein and a delay of 30 min between fucosylation of these polypeptides and their subsequent appearance in myelin as glycoproteins.
Asia and the Nation-State Most conference participants believe that, over the next twenty years, the fulcrum of world politics will continue to shift from Europe and its peripheries to the Asia-Pacific region. The period of European dominance produced innumerable wars as various countries challenged each other for power, resources, and sovereignty. With the formation of the European Union and the dissolution of the Warsaw Pact, great power rivalry in particular and the nation-state in general are fading somewhat in importance.
