Figure 2.

Genetic targeting of Glra2 impairs brain development. (a–f), newborn Glra2 KO mice have a smaller brain size, with reduced thickness of the cerebral cortex. Microphotography of brains from two distinct wild types (WT1, WT2) and two distinct Glra2 KO (KO1, KO2) newborn littermates at P0 (a). Half coronal brain sections of wild-type (b), WT) or Glra2 knockout (c), Glra2 KO) newborn littermates. Histograms representing measurements obtained on brain sections from newborn WT or Glra2-KO mice (see (b, c) for representative sections) showing brain dimensions (d), thickness of the cerebral cortex at different dorso-lateral levels (e) and striatum areas (f). Values are expressed as mean±S.E.M., n=10 and 18 brain sections taken from three and five brains per genotype; *P<0.05, ***P<0.001, t-test. (g-i) Immunolabelings showing cortical GFP-expressing interneurons (green) on brain sections from newborn WT or Glra2 KO littermates (g); nuclei are stained with Hoechst, red. Histogram of the average number of interneurons per field (h); mean±S.E.M., n=6 and 7 brain sections taken from three brains per genotype; ***P<0.001, t-test.). (i), number of VZ and SVZ cycling cells that express Ki67 (mean±S.E.M., n=11 and 14 brain sections taken from 3 brains per genotype; * P<0.05, t-test). Scale bar, 5 mm (a), 1,000 μm (c). D, dorsal; D-L, dorso-lateral; L, lateral; D-V, dorso-ventral; M-L, medio-lateral