Table 1.

Ontogenetic astrocyte progenitor pools

	Radial glia	Postnatal glial progenitor cells	Glial restricted precursors
Origin	Neuroepithelial cells [1]	• Radial glia [11, 12]	Neuroepithelial cells skipping the radial glia stage [13, 14]
		• Dlx2 (distal-less homeobox 2) [3]
		• Local glial progenitors [1]
Location	Ventricular zone [1]	• Subventricular zone	• Embryonic spinal cord [8]	• Optic nerve [8]
		• Dorso-lateral subventricular zone
		• Marginal zone [1, 11, 12]
Characteristics	Multipotential cells [11, 12]	• Multipotential cells	Tripotential cells [8]	• Bipotential cells O-2A, O-2A/OPC [8, 15]
		• Bipotential cells [3]
Roles	• Progenitors for neurons and glial cells	• Intermediate progenitors for astrocytes and oligodendrocytes [3]	• Promote neuroprotection	• Tumor genesis (oligoastrocytomas, multiform glioblastomas) [15]
	• Guidance of neuronal migration [11, 12]		• Reduction of glial scar
			• Formation and axonal growth [8]
Type of resulting astrocytes	• Star shaped specialised cortical astrocytes	• Cortical astrocytes	• Self-renewal	• Astrocytes type 2 and oligodendrocytes (in vitro)
		• White matter astrocytes	• Astrocytes types 1, 2 and
	• Bergmann glia in the cerebellum [3, 16]	• Oligodendrocytes [3]	• Oligodendrocytes [8]	• Oligodendrocytes (in vivo) [8, 15]