Figure 3.

EdU birthdating demonstrated a CPN migratory defect in Mllt11 cKO mutants. A, B, EdU birthdating of UL CPNs by injection at E14 showed altered distribution in Mllt11 cKOs at E18.5, reflecting an apical shift in expression correlating with the decreased cortical thickness. B, Apical shift in migrating CPNs in cKOs relative to controls following an EdU pulse at E16 (B). C, Proliferating cells labeled with a short pulse of EdU at E14 showed no significant differences in numbers or distribution between controls and cKOs. D, No significant difference in numbers of nuclei labeled by a short pulse of EdU at E18 populating most bins in cKOs versus controls, but a greater proportion of cells were retained in the cKO VZ region. E, F, Pial sections at E14.5 (E) and E18.5 (F) showed comparable levels of expression of CR markers P73 and Reelin in L1 of cKOs versus controls. Line charts represent percentage of positive cells per 100 × 100 μm bin as a proportion of total EdU+ cells. Total co-labeled cells are shown as bar graphs. Student's t test with Welch's correction, (A, C, E) N = 4, (B, D, F) N = 3. Data presented as mean ± SD n.s., not significant; *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, ****p ≤ 0.0001. Scale bar: 50 μm (A–F). VZ, ventricular zone. CPN, cortical projection neuron. See Extended Data Figure 3-1.