Figure 1.

Expression of functional GlyRs during embryonic cortical development. (a, b) Immunolabelings performed on a brain section from WT or Glra2 KO (a, left and right, respectively) E13 embryos showing GlyR α2-subunit immunostaining in the cortical wall (GlyRα2, red; arrows point strong signal in cells bordering the lateral ventricle and asterisks show non-specific staining in a. The expression pattern of GlyRα2 changes during development (b); nuclei are stained in blue with Dapi). (c, d) Apical and basal progenitors express GlyR α2-subunit (GlyRα2 in blue or white, Tbr2 in red and GFP in green). Arrows point either an apical or a basal progenitor on single confocal plane (c). Expression of GFP (green) in cycling APs and BPs 24 h after retroviral infection in cultured slices (see scheme on the left, (d). (e–g) Whole-cell patch-clamp analyses performed on cycling APs and or BPs in acute E13 brain slices. Representative traces of glycine-elicited currents obtained in APs after bath application of successive increasing glycine concentrations (e). Concentration-response curve obtained in BPs from successive bath application of increasing glycine concentrations (f). Representative traces of strychnine (STR) inhibition of glycine-elicited currents obtained in a BP (g). (h) Intracellular Ca²⁺ oscillations recorded in the cortical wall of brain slices loaded with Fluo4 AM (green). Representative traces of Ca²⁺ oscillations in representative cells (1–4, circled in yellow in the corresponding picture) induced by glycine application, as indicated. Scale bar, 65 μm (a), 100 μm (b), 25 μm (c), 50 μm (h). CP, cortical plate; IZ, intermediate zone; MZ, marginal zone; SVZ, subventricular zone; VZ, ventricular zone