Compartmentation in mammalian cerebellum: Zebrin II and P-path antibodies define three classes of sagittally organized bands of Purkinje cells.

The respective roles of genetic and epigenetic factors in generation of pattern formation in the vertebrate nervous system are still poorly elucidated. The mammalian cerebellum is subdivided in parasagittal modules defined by anatomical, physiological, and biochemical criteria. Immunostaining of adult mouse cerebellum with two monoclonal antibodies, P-path, which recognizes 9-O-acetylated glycolipids, and Zebrin II, which recognizes a 36-kDa protein, reveals three classes of sagittally organized bands of Purkinje cells: two complementary groups distinctly immunoreactive to one antibody but not the other and a third group that contains double-labeled cells. No Purkinje cells could be detected that were unreactive to either antibody. The specific and reproducible topography of these three classes of Purkinje cells may be related to the compartmentation of the cerebellum into developmental genetic modules.