Figure 3. Dgcr8 ablation leads to increased generation of Tbr1⁺ neurons.

• A–F’
  Immunofluorescence microscopy of coronal cryosections through the dorsal telencephalon of E13.5 WT (A, A’, D, D’), Dgcr8 cHET (B, B’, E, E’), and Dgcr8 cKO (C, C’, F, F’) littermate mouse embryos, subjected to two BrdU administrations from E12.5. Double immunostaining for BrdU (A–F, cyan) and Tbr1 (A’–C’, green), or triple immunostaining for BrdU, Tbr2 (D’–F’, magenta), and Tuj1 (D’–F’, green). Arrowheads and arrows indicate categories of counted cells as shown in Appendix Fig S3. Asterisks indicate the ventricular lumen. Solid and dashed lines indicate cortex boundaries. Cortical plate (CP); subventricular zone (SVZ); ventricular zone (VZ). Scale bars: 50 μm.
• G
  BrdU injection scheme (up) and quantification (down) of the proportions of Tbr1⁺ neurons (BrdU⁺/Tbr1⁺, green bars), Tbr2⁺ basal progenitors (BrdU⁺/Tbr2⁺, pink bars), and apical progenitors (BrdU⁺/Tbr1⁻/Tbr2⁻, cyan bars) generated in 24 h in similar sections as shown in (A–F’). Apoptotic nuclei are excluded from all the quantifications. Bars are mean ± SEM of three embryos per condition (18 counted fields per condition). One‐way ANOVA, *P < 0.05; ****P < 0.0001.