SOX3 is not expressed in the cells committed to cerebellar Purkinje neuron lineage. Sagittal sections of the 14.5 dpc (A), 16.5 dpc (B), 18.5 dpc (C), and P21 (D) cerebella. Cii Higher magnification of 18.5 dpc wildtype cerebellum showing that SOX3+ cells (green) are interpersed with Calbindin+ Purkinje cell (red). (D) Higher magnification reveals the close anatomical association between the SOX3+ cells (arrows) and PCs in P21 cerebellum. BG bergmann glial cells; Scale bar 100 µm.