Involved in both glial cell differentiation and axonal network formation during neurogenesis. Promotes astrocyte differentiation and transforms cerebellar astrocytes into radial glia. Also induces axonal extension in small and intermediate neurons of sensory ganglia by activating nearby satellite glia. Monomer. Highly expressed in brain. Expressed in undifferentiated neural progenitors and in astrocyte lineage, particulary in Bergmann glia, a subtype of radial glia, and a few discrete neuronal populations residing in the superior colliculus, the ocular motor nucleus, the raphe and pontine nuclei, and in various thalamic nuclei. Weakly expressed in heart, kidney, skeletal muscle, spleen, testis, gut and lung. By all-trans retinoic acid (ATRA). Was called meteorin because it can transform glial cells into cells with an elongated trail. Belongs to the meteorin family.