Chapter 6 - Functions of Gap Junctions in the Developing Neocortex

Abstract

Gap junctions allow the direct communication between two cells via cytoplasmic connections. They are involved in every major step of neocortical development. During embryogenesis, connexins play a role in cell cycle regulation and in cell fate determination. Furthermore, they are necessary for radial migration of postmitotic cells into the neocortex. Within the subplate, neurons are interconnected via gap junctions. The synchronized activity of these neuronal clusters may be important for the development of cortical columns. During the postnatal period, gap junctions have been found in both pyramidal cells and GABAergic interneurons. These neuronal clusters emerge before the period of circuit formation and are involved in experience-dependent synaptogenesis and synaptic plasticity. In the past decade, knowledge about the functions of gap junctions in the development of the neocortex has increased. However, for a comprehensive understanding of these functions, additional physiological information from more refined genetic mouse models is needed.