NG2-glia, also called Oligodendrocyte Precursor Cells (OPCs), account for approximately
5%-10% of the cells in the developing and adult brain and constitute the fifth major cell
population in the central nervous system. NG2-glia express receptors and ion channels involved in
rapid modulation of neuronal activities and signaling with neuronal synapses, which have functional
significance in both physiological and pathological states. NG2-glia participate in quick signaling
with peripheral neurons via direct synaptic touches in the developing and mature central nervous
system. These distinctive glia perform the unique function of proliferating and differentiating into
oligodendrocytes in the early developing brain, which is critical for axon myelin formation. In response
to injury, NG2-glia can proliferate, migrate to the lesions, and differentiate into oligodendrocytes
to form new myelin sheaths, which wrap around damaged axons and result in functional recovery.
The capacity of NG2-glia to regulate their behavior and dynamics in response to neuronal
activity and disease indicate their critical role in myelin preservation and remodeling in the physiological
state and in repair in the pathological state. In this review, we provide a detailed summary of
the characteristics of NG2-glia, including their heterogeneity, the regulators of their proliferation,
and the modulators of their differentiation into oligodendrocytes.
