Injuries severing the axon from the cell body can cause permanent nerve damage. Peripheral nervous system neurons can recover by regenerating their axons, but central nervous system neurons cannot. Understanding the mechanism behind peripheral axon regeneration is important. Our projects investigate the roles of microtubules and the endoplasmic reticulum in axon regeneration. Here we identify the proteins involved in microtubule polarity reorganization, and calcium signaling and lipid synthesis by the endoplasmic reticulum during axon regeneration.