Neural progenitors proliferation is inhibited by EphB3 in the developing subventricular zone.

The subventricular zone (SVZ) of the mammalian forebrain is a major source of multipotent stem cells during development, and contributes to neurogenesis throughout the lifespan of the organism. Several studies described molecules regulating adult neurogenesis, however, few of them have examined neurogenesis in the early postnatal period. Adult neurogenesis is regulated in part by ephrinB3 and its receptors, so we examined the role of EphB3 on neural stem/progenitor cell (NSPC) proliferation in early postnatal development in the SVZ. To examine NSPC proliferation, we used BrdU incorporation in both cultured NSPCs and neonatal gene-targeted knockout mice, as well as Ki67 immunostaining in EphB3(-/-) mice. We observed a significant increase in proliferation in cultured NSPCs derived from EphB3(-/-) mice and in the SVZ of EphB3(-/-) mice. These studies support an anti-proliferative role for EphB3 in regulating NSPC numbers in the developing SVZ.