THE DISTRIBUTION OF MYELIN BASIC-PROTEIN MESSENGER-RNAS WITHIN MYELINATING OLIGODENDROCYTES

The nervous system contains oligodendrocytes with processes that are g reatly extended in space. It is now clear that there are numerous comp lex, poorly understood mechanisms by which polypeptides are synthesize d and delivered to their sites of function in these cells. One mechani sm is by the active positioning of mRNAs encoding certain proteins to restricted intracellular subdomains. Perhaps the best studied example of this in the vertebrate CNS is the translocation of myelin basic pro tein mRNAs to the forming myelin sheath, where the newly synthesized p olypeptides, which avidly associate with membranes, can be directly in corporated into the myelin membrane. Evidence for this conclusion is p resented here in the context of related work on the general phenomenon of mRNA translocation that is under analysis in other systems.