Fig. 4.

Igsf21, Pde10a and Btbd3 expression in the Cx of a Fgf8^null/neo mouse in perinatal stages (E17.5). In situ mRNA hybridization in transversal brain sections of Igsf21, Pde10a and Btbd3 genes in control (a–i) and in Fgf8^null/neo (a′–i′) mice. Images are adjacent sections, ordered from rostral to caudal, obtained from the same animal to match the different areas accurately (j–l′). Color-coded overlays of hybridizations for Igsf21 (red), Pde10a (green) and Btbd3 (blue) genes in E17.5 transversal sections of control (j–l) and Fgf8^null/neo (j′–l′) embryos, from rostral to caudal (j to l and j′ to l′, respectively). Arrowheads indicate the clear subplate cell layer (SP) in the wild type (a) that appears disorganized in the Fgf8^null/neo mouse. The overlap of the three genes confirms the complementary expression pattern in this region in the control, but not Fgf8^null/neo mice, where the anterior nuclear complex is not apparent and there is a reduction of ventral-lateral nuclei, which are invaded by the dorso-lin ateral marker gene. The boundary between dorsal and ventral nuclei is disrupted by bidirectional cellular dispersion across its domain. l″ is a caudal transversal section from an Fgf8^null/neo mutant mouse, immunostained against caspase 3, where VPM/L is clearly affected. Scale bar: 200 µm