No Pasaran! Role of the axon initial segment in the regulation of protein transport and the maintenance of axonal identity

- The axon initial segment (AIS) has a key role in the maintenance of neuronal polarity.
- The AIS is a large assembly of membrane proteins bound to an ankyrin G based scaffold.
- The AIS forms a surface diffusion barrier and an intracellular traffic filter.
- The cytoskeleton arrangement suggests molecular mechanisms for the barrier and filter.