Cytoskeletal control of axon domain assembly and function.

•Neuronal polarity and polarized trafficking depends on microtubule specializations.•The axonal cytoskeleton consists of periodic rings of actin, spectrins, and ankyrins.•Nodal ion channels are clustered by a hierarchy of ankyrin/spectrin complexes.•The membrane boundary flanking nodes is the βII spectrin-dependent cytoskeleton.