Fig. 5

Telencephalic progenitors give rise to gad67- and/or TH-positive neurons in the OB and in the anterior subpallium and medial pallium. Localization of GABA-ergic neurons, revealed by gad67 (A–C, F, I) (ISH, blue or black) expression and compared with the expression of TH (D–I) (immunodetection, green) and/or the localization of BrdU-positive cells after 4 weeks of tracing (B, C, E, H) (red). Panels B and D–F are focussed on the OB, panels C and G–I on the subpallium and medial pallium, white arrows to the midline. All views are cross-sections, anterior up, panels B–I are confocal photomicrographs. In the OB, newborn neurons in the IL largely express gad67 (B, red arrows to examples of double-positive cells, one example is magnified in inset). Most TH-positive neurons in the GL (D) are gad67-positive (F, green arrows to examples of double-positive cells) and a subset of these neurons are newborn (E). In the subpallium and medial pallium, gad67 expression is organized in three bilateral columns (numbered 1–3 in A, C, I), which largely contain newborn neurons (C red arrows to examples of double-positive cells, one example is magnified in inset). Some newborn neurons also express TH (H), but these are mostly not GABAergic (I, green arrow to the restricted subpopulation of gad67/TH double-positive cells).