Cycling or not cycling: cell cycle regulatory molecules and adult neurogenesis

Abstract

The adult brain most probably reaches its highest degree of plasticity with the lifelong generation and integration of new neurons in the hippocampus and olfactory system. Neural precursor cells (NPCs) residing both in the subgranular zone of the dentate gyrus and in the subventricular zone of the lateral ventricles continuously generate neurons that populate the dentate gyrus and the olfactory bulb, respectively. The regulation of NPC proliferation in the adult brain has been widely investigated in the past few years. Yet, the intrinsic cell cycle machinery underlying NPC proliferation remains largely unexplored. In this review, we discuss the cell cycle components that are involved in the regulation of NPC proliferation in both neurogenic areas of the adult brain.

Fig. 1

Cell cycle regulation in the adult SGZ and SVZ compared to the classical model of the cell cycle. The dashed line on Cdk2 in the SGZ cell cycle indicates its dispensability to the process. Variations of cell cycle and cell cycle phase durations may represent a key aspect of the regulation of NPC proliferation in the adult brain, as it does during embryonic brain development