Apical abscission, a novel cell biological mechanism regulating neurogenesis

Abstract

Withdrawal of differentiating neurons from the ventricle of the neural tube is a highly regulated process that is critical for the formation of normal tissue architecture and neural circuitry. We have recently reported a novel cell-biological event that mediates this process and involves local abscission of the apical cell-compartment as cells become neurons. Apical abscission takes place as adherens junctions are lost, depends on actinomyosin contractility, results in loss of apical cell polarity as well as dis-assembly of the primary cilium, and allows cell cycle exit. The molecular mechanisms mediating the series of steps underlying apical abscission are complex and inter-linked and open up many new questions. In this commentary we discuss how these mechanisms may operate and the functions of apical abscission during neurogenesis, in disease, and in other cell biological processes that involve withdrawal of cells from epithelia.