NOTCH RECEPTOR ACTIVATION INHIBITS OLIGODENDROCYTE DIFFERENTIATION

In this study, we show that oligodendrocyte differentiation is powerfu lly inhibited by activation of the Notch pathway. Oligodendrocytes and their precursors in the developing rat optic nerve express Notch1 rec eptors and, at the same time, retinal ganglion cells express Jagged1, a ligand of the Notch1 receptor, along their axons. Jagged1 expression is developmentally regulated, decreasing with a time course that para llels myelination in the optic nerve. These results suggest that the t iming of oligodendrocyte differentiation and myelination is controlled by the Notch pathway and raise the; question of whether localization of myelination is controlled by this pathway.