Radial Glia, the Keystone of the Development of the Hippocampal Dentate Gyrus

The morphogenesis of the dentate gyrus (DG) of the hippocampus primarily occurs postnatally, and the DG is one of the few regions of continuous neurogenesis in the adult brain. Radial glial cells (RGCs), which contribute to DG development by participating in key steps of morphogenesis, are maintained in the subgranular zone (SGZ), where they play pivotal roles in adult hippocampal neurogenesis. It is clear that a series of molecules control the development of RGCs, thereby regulating the morphogenesis of the DG and neurogenesis in the adult hippocampus. In this review, we provide an updated framework regarding the molecular mechanisms involved in the development of RGCs during DG morphogenesis and discuss the key steps that regulate DG formation.