Fig. 4: PV cells show prematurely rich perisomatic innervation in Tg(Nkx2.1-Cre);Tsc1^flox/flox and Tg(Nkx2.1-Cre);Tsc1^flox/+ mice at EP18.

a1 A PV cell (green) amongst NeuN immunostained neurons (in blue) in cortical organotypic culture from a Tsc1^Ctrl mouse at EP18. a2 PV cell from Tsc1^Ctrl slice shows characteristic branching and multiple boutons (arrowheads) on the postsynaptic somata (a3). PV cells from Tg(Nkx2.1-Cre);Tsc1^flox/+ mice (b1–b3) and Tg(Nkx2.1-Cre);Tsc1^flox/flox mice (c1–c3) show increased bouton density (d) (one-way ANOVA, **p = 0.0039; Holm–Sidak’s multiple comparisons: Tsc1^Ctrl vs Tg(Nkx2.1-Cre);Tsc1^flox/+ **p = 0.0023; Tsc1^Ctrl vs Tg(Nkx2.1-Cre);Tsc1^flox/flox *p = 0.0242). Number of mice: Tsc1^Ctrl n = 7, Tg(Nkx2.1-Cre);Tsc1^flox/+ n = 7, Tg(Nkx2.1-Cre); Tsc1^flox/flox n = 6. e Local branching (one-way ANOVA *p = 0.0113 (Radius 8), **p = 0.0096 (Radius 9); Holm–Sidak’s multiple comparisons: (Radius 8) Tsc1^Ctrl vs Tg(Nkx2.1-Cre); Tsc1^flox/+ *p = 0,0155; Tsc1^Ctrl vs Tg(Nkx2.1-Cre); Tsc1^flox/flox *p = 0.0425, Tg(Nkx2.1-Cre); Tsc1^flox/+ vs Tg(Nkx2.1-Cre); Tsc1^flox/flox p = 0.8062; (Radius 9) Tsc1^Ctrl vs Tg(Nkx2.1-Cre); Tsc1^flox/+ *p = 0.0317; Tsc1^Ctrl vs Tg(Nkx2.1-Cre); Tsc1^flox/flox *p = 0.0148, Tg(Nkx2.1-Cre); Tsc1^flox/+ vs Tg(Nkx2.1-Cre); Tsc1^flox/flox p = 0.9738). Number of mice: Tsc1^Ctrl n = 7, Tg(Nkx2.1-Cre);Tsc1^flox/+ n = 5, Tg(Nkx2.1-Cre); Tsc1^flox/flox n = 6. f Percentage of innervation (one-way ANOVA, *p = 0.0254; Holm–Sidak’s multiple comparisons: Tsc1^Ctrl vs Tg(Nkx2.1-Cre); Tsc1^flox/+ p = 0,0823; Tsc1^Ctrl vs Tg(Nkx2.1-Cre); Tsc1^flox/flox *p = 0.0168). Number of PV cells: Tsc1^Ctrl n = 8, Tg(Nkx2.1-Cre); Tsc1^flox/+ n = 6, Tg(Nkx2.1-Cre); Tsc1^flox/flox n = 7. Scale bars: a1–c1, 20 µm; a2–c2, 10 µm, a3–c3, 3 µm. Data represent mean ± SEM. Source data are provided as a Source Data file.