Figure 4

Apoptosis in the cerebral cortex is increased in mutant embryos at embryonic day (E)13.5. (A, B) A few apoptotic cells were detected by TUNEL staining in the control. (B) A higher magnification of the boxed area in (A) with white arrow indicating TUNEL⁺ cell (green staining). (C, D) Examples of the mutant showing increased apoptosis in the cerebral cortex (E) Quantification of apoptotic nuclei in sections of control and mutant cerebral cortex shows a large increase in apoptosis in the mutant. Student's t-test p-values are indicated above bars. Error bars are standard error of the mean. All sections are coronal and dorsal is up. Scale bars: (A, C) 400 μm; (B) 50 μm; (D) 200 μm.