Source: Stanford University Medical Center
Date: March 10, 2010
Summary:
About four out of every 10 cells in the brain are so-called oligodendrocytes. These cells produce the all-important myelin that coats nerve tracts, ensuring fast, energy-efficient transmission of nerve impulses. Mixed among them are proliferating but not particularly proficient precursor cells that are destined to become oligodendrocytes when needed but, for now, remain suspended in an immature, relatively undifferentiated state somewhere between stem cell and adult oligodendrocyte.
Stanford University School of Medicine scientists have now identified a molecular master switch that catalyzes these cells' transition to mature, myelin-making mavens. The results may have implications for medical treatment, as defects in this maturation process have been observed in both multiple sclerosis and the most common kind of brain cancers in adults, known as gliomas.
In a study to be published March 10 in Neuron, the investigators found that a molecule known as miR-219 is found at high levels only in oligodendrocytes, and that it is both necessary and sufficient to induce their relatively undifferentiated precursors to become functioning adult cells.
