Sox2-Dependent Regulation of Neural Stem Cells and CNS Development

Abstract The essential role of SOX2 in embryogenesis was first demonstrated by the Sox2 gene knockout in mouse, leading to early embryonic lethality by loss of the epiblast, the founder tissue of the embryo proper. However, later in development, SOX2 expression is also a conserved marker of the developing central nervous system (CNS), and therein of neural stem cells (NSC), the self-renewing precursors of neurons, astrocytes, and oligodendrocytes. Genetic manipulation of Sox2 in mouse and other animal systems revealed an essential role for SOX2 in the development of multiple CNS regions and in the maintenance of NSC. Some differentiated neural cell types also require SOX2. Brain defects in mouse mutants mirror defects found in patients heterozygous for SOX2 mutations. Multiple transcriptional regulators, including cell cycle-control genes, act on SOX2 neural expression; in turn, SOX2 target genes have begun to be identified that have important roles in its biological function.