Fig. 2. Zeb2 regulates the multipolar stage.

(A to I) Zeb2 regulates onset of radial migration and restricts tangential movement of multipolar cells. (A) E14.5 Zeb2^fl/fl animals were in utero electroporated with a flox-mCherry-Stop-flox-GFP reporter and limiting amounts of Cre. Cre recombination excises Zeb2 and enables GFP expression (KO). Unrecombined cells express mCherry (WT). Brain slices were imaged for 51 hours, 1 day after IUE. (B) Distribution of radial migration onset. N = 37 mCherry⁺ and 34 GFP⁺ cells. (C) Clips from a time-lapse movie showing migration of WT and KO cells. Asterisks mark the soma. Migration onset (D) and speed (E) of neurons undergoing migration. N = 46 mCherry⁺ and 41 GFP⁺ cells. Mann-Whitney and unpaired t test. (F) Traces of individual neurons undergoing migration. (G) Movement of multipolar cells in the SVZ (0 to 20 hours). Scale bar, 5 μm. A red dot marks the start and a green triangle marks the end position. Tangential spread (H) and speed (I) of neurons in the SVZ. N = 15 WT and KO cells. Unpaired t test. (J and K) Zeb2 regulates multipolar morphology. (J) Zeb2^fl/fl and Zeb2^fl/fl Nex^Cre animals were in utero electroporated at E15.5 with GFP and their morphology in the SVZ was analyzed 36 hours later. Scale bar, 50 μm. (K) Number of primary neurites per cell. N = 20 Zeb2^fl/fl and Zeb2^fl/fl Nex^Cre cells. Unpaired t test.