D Detection of the corrected total cell fluorescence (CTCF) of the β-Gal reporter in Nestin-, Tbr2-, DCX- and Calbindin-positive cells in BATGAL mice corroborate stage specific activity pattern of canonical Wnt signaling during lineage progression [Nestin vs. Tbr2 p <0.0001, Tbr2 vs. DCX p=0.0029, DCX vs. Calbindin p<0.0001] (Nestin: n= 236 cells, Tbr2: n= 134 cells, DCX: n= 200 cells, Calbindin: n= 300 cells). 