Fig. 3. Ablation of the KDM2B-CxxC impedes the migration of intermediate progenitors and production of granule cells.

a EdU was administrated at E15.5 and double labeling of PROX1 and EdU was performed on P2 coronal sections. Dashed lines indicate DG and FDJ. b, c Quantification of PROX1+ (b) and PROX1+EdU+ (c) cells in the FDJ and DG. d Quantification of total PROX1+EdU+ cells in hippocampi. e Quantification of EdU+ cells in the DG. f The 3ry matrix was divided into 10 ventral- -to-dorsal bins spanning the lower to upper blade domain. g The percentage of PROX1+ cells in each bin is represented. h Quantification of the percentage of PROX1+ granule neurons positioned in the lower blade (bins 1–5), versus the upper blade (bins 6–10) in P2 control and Kdm2b^Emx1-ΔCxxC DGs. i Double immunofluorescence of TBR2 (green) and GFAP (red) on P0 wild-type and Kdm2b^Emx1-ΔCxxC hippocampi. Boxed regions of FDJ and DG were enlarged on the right. j, k The schematic of P0 wild-type and Kdm2b^Emx1-ΔCxxC hippocampi. l, m Distribution of TBR2+ cells along the three matrices, where dashed lines demarcate regions designated as the 1ry, 2ry, and 3ry matrix (l). n = 6 for control brains and n = 4 for Kdm2b^Emx1-ΔCxxC brains. n Quantification of the area of fimbria. o Quantification of GFAP immunofluorescence (pixel area) in the 2ry and fimbria. Cartoons in (f), (j) and (l) are adapted from Caramello et al.³⁶. n = 5 for control brains and n = 4 for Kdm2b^Emx1-ΔCxxC brains (a–h). n = 3 for control brains and n = 3 for Kdm2b^Emx1-ΔCxxC brains (n–o). Data are represented as means ± SEM. Statistical significance was determined using an unpaired two-tailed Student’s t-test (d, e, m left, n), or using two-way ANOVA followed by Sidak’s multiple comparisons test (b, c, g, h, m right, o). *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001. Scale bars, 500 μm (a), 100 μm (i). DG dentate gyrus, DMS dentate migratory stream, FDJ fimbriodentate junction, HF hippocampal fissure, 1ry primary matrix, 2ry secondary matrix, 3ry tertiary matrix.