Zones and Stripes

The cerebellar cortex is built around different classes of Purkinje cell, which form an array of transverse zones, each of which is further divided into parasagittal stripes. There are >200 stripes, which are reproducible between individuals and the pattern is conserved across birds and mammals. Other features of cerebellar organization, including the topography of afferent projections and cerebellar interneurons, are built around the Purkinje cell framework. Zone and stripe architecture is established early in cerebellar development. Purkinje cells are born between E10 and E13 (in mouse) in the subventricular zone of the fourth ventricle. Purkinje cell subtype specification likely happens at this time. Postmitotic Purkinje cells migrate into the cerebellar anlage and form a stereotypes array of clusters (E14–E18). Clusters are the forebears of the stripes and are the targets of the ingrowing afferent projections. Reelin signaling at around birth triggers the rostrocaudal dispersal of the clusters into the adult stripes.