Abstract: Oligodendrocytes and their cell-intrinsic gene regulatory network: Oligodendrocytes (OLs) are the myelinating glial cells of the vertebrate central nervous system. They are responsible for insulating neuronal axons with a lipid-rich myelin sheath, which enables the saltatory conduction of action potentials. During development, oligodendrocyte progenitor cells (OPCs) emerge from neural stem cells in the ventricular zone. They then proliferate, increase their number, and migrate to their final destination where they encounter unmyelinated neuronal axons and differentiate in a stepwise fashion into myelinating oligodendrocytes (mOLs) under the influence of environmental stimuli.