BIOLOGY OF NEUROBLAST MIGRATION IN THE DEVELOPING CEREBRAL CORTEX

In-depth knowledge of normal migration behavior of neuroblasts during neocortical development is critical for better understanding of pathophysiology of neuroblast migratory disorders. Two distinct neuronal populations of the neocortex, that is, non-GABAergic projection neurons and GABAergic inhibitory interneurons, are generated from two distinct progenitor populations in the developing forebrain. Projection neurons are generated from neuronal progenitor cells surrounding the lateral ventricles of the telencephalon: interneurons are generated in the medial ganglionic eminences of the developing forebrain. It was long believed that all of newly born projection neurons migrate towards the pial surface guided by scaffold structure known as radial glia. However, recent researches revealed variable migration patterns of projection neurons including translocation, locomotion, and multipolar migration. Additionally, modes of tangential migration of interneurons from the ganglionic eminence have been thoroughly investigated. In this talk, I will summarize recent knowledge regarding the biological mechanisms of normal migration patterns, dysregulation of which may lead to neuroblast migratory disorders.