Figure 2.

Transcription factors, growth factors, signaling pathways, and markers of cell identity associated with different stages of oligodendrocyte precursor cell (OPC) maintenance and differentiation. OPC proliferation and self-renewal depend on PDGFα–PDGFRα signaling, high Wnt tone, and PKC activation. Insulin, T₃, and cortisol disinhibit differentiation of OPCs into mature oligodendrocytes (OLs), likely through counteracting PKC activation. OPCs can be induced to differentiate into Type 2 astrocytes by BMPs and IFNγ. Although some evidence suggests that OPCs express proneural transcription factors such as Sox2 and Pax6, and neuronal precursor markers such as doublecortin (DCX), it is unknown whether OPCs give rise to appreciable numbers of neurons in vivo.