Title: Adhesion and Endocytosis in Neuronal Migration
Jennifer Shieh Graduate Student Stanford University
The dynamic dance of the nomadic neuron begins at birth.
Act I: Interkinetic Nuclear Migration In the cerebral cortex, neural progenitors divide to give birth to more cells at the surface of the ventricle (the fluid-filled hole in the middle of your brain).
Act II: Indecision The newborn cortical neuron migrates out to the surface of the brain, attracted and repelled by various guidance cues. These neurons pass through a multipolar stage where they may be deciding what direction to go or where to project their axon.
Act III: Directed Radial Migration The physical movement of a neuron is much like the old PE rope-climbing exercises. A hand-over-hand extension of the leading process that must stick to a radial glial guide, followed by the thickening of part of the cytoplasm in front of the nucleus, and finally the forward movement of the cell body. For the cell body to move forward, adhesions must be weak. Endocytosis, the internalization of bits of membrane, might help weaken those adhesions, allowing the cell to let go and the cell body to move forward.
Act IV: Finding Your Fate Once the neuron reaches its final destination, it can fulfill its fate and take its place as a fully functioning member of the brain.