Fig. 7. Inverted cortex in CxCdk5KO mice. (A) Bin distributions of BrdU-positive cells shown as mean percentage of three mice for control (Cont.) and CxCdk5KO mice (CxCdk5KO) at indicated time points. The cortical mantle was divided into ten equally spaced bins, and the percentage of BrdU-positive cells in each bin is shown. Birth-dating BrdU labelling from E12.5 to E16.5 revealed a typical inside-out pattern of generation of the laminar structure in the cerebral cortex of control mice at P10. This pattern was inverted, resulting in an outside-in pattern in the motor cortex (a) and somatosensory cortex (b) of CxCdk5KO mice. (B) In situ hybridisation study with layer markers Cux2, Er81 and Foxp2 at P10. In the control, Cux2-positive, Er81-positive and Foxp2-positive neurons accumulated in layer II/III, layer V and layer VI, respectively. This pattern was inverted in the CxCdk5KO cortex. Scale bar: 100 µm.