Figure 1.

Elimination of GABA transmission from ErbB4⁺ interneurons during postnatal development. A, Genetic strategy for postnatal ablation of Vgat in ErbB4⁺ interneurons. Erbb4^CreER and Erbb4^CreER;Vgat^fl/fl mice were crossed with LSL-tdTomato (Ai9) mice to visualize ErbB4⁺ neurons. B, Tam administration and experimental timeline. C, Reduced VGAT in the brain tissues of Tam-treated Erbb4^CreER;Vgat^fl/fl mice compared with vehicle-treated controls at P35. D, Quantitative data of C (n = 3 mice per group, PFC: p = 0.04; Ctx: p = 0.003; HPF: p = 0.03). E, Comparable growth rate of vehicle- and Tam-treated Erbb4^CreER;Vgat^fl/fl mice. F, Kaplan–Meier survival curves of control and ErbB4-Vgat^−/− mice (n = 21 and 22 mice, respectively). G, VGAT reduction in ErbB4-Vgat^−/− mice. H, Quantitative data of G. I, J, Representative coronal sections were immunolabeled with antibody against VGAT. Higher magnification of dotted areas is shown in images on the right (ErbB4, red; VGAT, green). Closed arrowheads indicate VGAT punctae colocalized with ErbB4⁺ boutons; open arrowheads indicate VGAT punctae not colocalized with ErbB4⁺ boutons. K, Decreased number of VGAT punctae associated with ErbB4⁺ boutons in ErbB4-Vgat^−/− mice. Control, n = 46 ROIs, 9 sections, 3 mice; ErbB4-Vgat^−/−, n = 35 ROIs, 9 sections, 4 mice. L, Decreased VGAT intensity in ErbB4⁺, but not ErbB4⁻ (ErbB4-negative), boutons in ErbB4-Vgat^−/− mice. VGAT-ErbB4⁺: control, n = 36 ROIs, 9 sections, 3 mice; ErbB4-Vgat^−/−, n = 20 ROIs, 9 sections, 4 mice. VGAT-ErbB4-: control, n = 14 ROIs, 9 sections, 3 mice; ErbB4-Vgat^−/−, n = 19 ROIs, 9 sections, 4 mice. PFC, Prefrontal cortex; Ctx, cortex; HPF, hippocampal formation. Error bars indicate SEM. n.s., Not significant. *p < 0.05; **p < 0.01; ***p < 0.001.