Nkx2-1-Cre-mediated deletion of Donson induces apoptosis in the mGE.

(A-L) Images and graphs represent Nkx2.1-cKO mice (cKO) and control (ctrl) littermates at E12.5 (a.-i.) and E14.5 (j.-l.). Mice carried a Rosa26^CAG-LSL-tdT allele. (A,B) Confocal images demonstrate native tdT and immunostaining for CC3 in the mGE and mPO of ctrl and cKO mice. The inset in (b.) shows apoptotic cells in the VZ at high magnification. (C,D) Dual immunofluorescences demonstrate tdT and Gsh2 in the subpallium at E12.5. Note that tdT⁺ cells are missing in the subpallial mantle zone of the cKO (arrows). (E,F), Immunostaining for Olig2 in the mGE at E12.5. (G) Micrographs demonstrate Ascl1 in the E12.5 mGE and mPO after in situ hybridization with a ³⁵S-labeled probe (dark signals). (H,I) Scatter plots show quantifications of Ascl1 expression in the VZ of the mGE (h.) and the number of Lhx6⁺ cells in the mantle zone lateral to the lGE (i.); see arrow in (c.) for the evaluated region. Circles and triangles represent individual mice, horizontal lines represent the median. Measurements and statistics are summarized in S1E Table. (J) Confocal images demonstrate two sectional planes of the mGE at E14.5. The mGE is identified by strong tdT signal in the VZ and SVZ. (K) Confocal images show double immunofluorescences for tdT and Olig2 in the mGE at E14.5. (L) Epifluorescence image demonstrates CC3 in the mGE/ mPO area of an E14.5 cKO. Abbreviations: lGE and mGE, medial and lateral ganglionic eminence; mPO, medial preoptic area; MaZ, subpallial mantle zone; SVZ, subventricular zone; VZ, ventricular zone. Scale bars: 200 μm (a. and c.), 100 μm (e.), 200 μm (g.), 180 μm (j.), 150 μm (k.), 60 (l.) μm.