Stops and starts in microtubules.
D000818:Animals; D001369:Axons / Q000648:ultrastructure; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000648:ultrastructure; D002478:Cells, Cultured; D005347:Fibroblasts / Q000648:ultrastructure; D008870:Microtubules / Q000648:ultrastructure*; D009474:Neurons / Q000648:ultrastructure