Figure 1. Faithful expression of GAD67-GFP in cortical GABAergic neurons. A–P, Immunostaining of GAD67+ brain sections with GABA antibody at the stages indicated. GAD67-GFP signals (A, D, G, J, M) were colocalized with those of GABA (B, E, H, K, N, single images; C, F, I, L, O, merged images). More than 93% of GAD67-GFP cells are immunopositive for GABA at the stages examined (P, n = 4, SEM as indicated). Q–U, Similar migratory patterns of GABAergic neurons in heterozygous GAD67-GFP and wild-type cortex. Sections of E14.5 (Q, R) and E17.5 embryonic brains (S, T) of wild-type (Q, S) and GAD67-GFP het (R, T) mice are stained with anti-GABA antibody. Overall, migratory patterns appear to be the same in both brains at both stages. GABA+ cells in each section have also been counted in the somatosensory cortex (U), and no significant differences in the numbers of GABA+ cells are found between genotypes. Scale bars: (in A) A–O, 50 μm; (in Q) Q–T, 0.5 mm.