Role of Intermediate Progenitor Cells in Cerebral Cortex Development

• Published in: Developmental neuroscience Vol. 30; no. 1-3; pp. 24 - 32
• Main Authors: Pontious, Adria, Kowalczyk, Tom, Englund, Chris, Hevner, Robert F.
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland S. Karger AG 01.01.2008
• Subjects: Animals; Cell Differentiation - physiology; Cerebral Cortex - cytology; Cerebral Cortex - embryology; Cerebral Cortex - physiology; Gene Expression Regulation, Developmental - genetics; Humans; Mice; Mini Review; Nerve Growth Factors - genetics; Nervous System Malformations - genetics; Nervous System Malformations - metabolism; Nervous System Malformations - physiopathology; Neural Pathways - embryology; Neural Pathways - physiology; Neurons - cytology; Neurons - physiology; Signal Transduction - genetics; Stem Cells - cytology; Stem Cells - physiology; Radial glia; Eomes transcription factor; Short neural precursors; Tbr2 gene; Basal progenitor cells; Pax6 gene
• ISBN: 9783805584654; 3805584652
• ISSN: 0378-5866; 1421-9859
• DOI: 10.1159/000109848

Intermediate progenitor cells (IPCs) are a type of neurogenic transient amplifying cells in the developing cerebral cortex. IPCs divide symmetrically at basal (abventricular) positions in the neuroepithelium to produce pairs of new neurons or, in amplifying divisions, pairs of new IPCs. In contrast, radial unit progenitors (neuroepithelial cells and radial glia) divide at the apical (ventricular) surface and produce only single neurons or single IPCs by asymmetric division, or self-amplify by symmetric division. Histologically, IPCs are most prominent during the middle and late stages of neurogenesis, when they accumulate in the subventricular zone, a progenitor compartment linked to the genesis of upper neocortical layers (II–IV). Nevertheless, IPCs are present throughout cortical neurogenesis and produce neurons for all layers. In mice, changes in the abundance of IPCs caused by mutations of Pax6, Ngn2, Id4 and other genes are associated with parallel changes in cortical thickness but not surface area. In gyrencephalic brains, IPCs may play broader roles in determining not only laminar thickness, but also cortical surface area and gyral patterns. We propose that regulation of IPC genesis and amplification across developmental stages and regional subdivisions modulates laminar neurogenesis and contributes to the cytoarchitectonic differentiation of cortical areas.