Neural stem and progenitor cells have a central role in the development and evolution of the mammalian neocortex. In this review, we first provide a set of criteria to classify the various types of cortical stem and progenitor cells. We then discuss the issue of cell polarity, as well as specific subcellular features of these cells that are relevant for their modes of division and daughter cell fate. In addition, cortical stem and progenitor cell behavior is placed into a tissue context, with consideration of extracellular signals and cell-cell interactions. Finally, the differences across species regarding cortical stem and progenitor cells are dissected to gain insight into key developmental and evolutionary mechanisms underlying neocortex expansion.
Keywords: INM; apical and basal processes; asymmetric cell division; cell biology; cell cycle; cell fate determination; cell polarity; cilium; interkinetic nuclear migration; neocortex evolution; neural progenitors; neural stem cells; neuroepithelial cells; radial glia.