Fig. 7. Anteroposterior differences in the cortical lamination of the E18.5 Sey mutant. Transverse sections through the wild type (A-C) and Sey (D-F) frontal and the wild type (G-I) and Sey (J-L) occipital cortex. The dashed line on C,F,I and L demarcates the upper boundary of deep layers. Note the absence of granular cells of upper layers above the dashed line in F. Arrowheads in E and F mark the lateral limit of Svet1 expression. Svet1 cells are reduced in number but not completely missing in the SVZ of the mutant occipital cortex. Arrowheads in K mark the altered SVZ region. Note the presence of upper layer cells above the dashed line on L.