Regulates mitochondrial transport during axon regeneration. Increases the proportion of motile mitochondria by recruiting stationary mitochondria into the motile pool. Enhances mitochondria movement and neurite growth in both adult axons and embryonic neurons. Promotes neuronal survival and axon regeneration after nerve injury. May link mitochondria to the Trak1-kinesin motor complex via its interaction with MIRO1. Interacts with MIRO1. Expressed at high levels ovary, heart, testis, prostate, brain, spleen and colon. Expressed at very low levels in liver and thymus. Not expressed in peripheral blood leukocytes. Not or reduced expressed in lung, prostate, colon, pancreas and ovarian carcinomas. Belongs to the eutherian X-chromosome-specific Armcx family.