Fig. 4

Apoptosis of Akirin2 knockout cortical progenitors and neurons. a Sections from mid-E10 and E11 (a) control and knockout cortex were stained for the mitotic marker phospho-histone H3 (PH3; green), apoptotic cell marker CC3 (red), and DAPI (blue). At mid-E10, controls and knockouts exhibit a similar number of PH3+ profiles at the ventricular surface (c); a significantly higher number of CC3+ dying cells are observed close to the emerging preplate (a, d). The cell death progresses between E10 and E11 (b), with no apoptotic cells apparent at early E10; CC3+ cells appear at mid-E10, and their number increases at late E10 and peaks at E11. At E11, Akirin2 knockouts exhibit significantly fewer PH3-positive mitotic cells (a, c), CC3 staining is greatly increased (d, e), and the tissue is already thinner (a). Further analysis of the CC3+ cells indicates that a greater percentage of cell death occurs in cells close to the pial surface at the developing preplate (PP) compared with cells closer to the apical venticular surface (VZ; e). *p < 0.05,****p < 0.0001. LV, lateral ventricle. Scale bar: 200 μm