Fig. 5

Increasing HDAC1 rebalances histone acetylation and rescues proliferation and differentiation deficits of FMRP-deficient NPCs. a A schematic model showing that enhancing HDAC1 activities through either pharmacological or genetic reduction of MDM2 rebalances histone acetylation and rescues proliferation and differentiation of Fmr1 KO NPCs. b, c Western blot analyses of HDAC1 and FMRP protein levels in 6-mo NPCs treated with Nutlin-3 (n = 3). GAPDH was used as a loading control. d–f Western blot analyses of total and acetylated histone H3 (d, e) and histone H4 (d, f) in NPCs treated with Nutlin-3 (n = 3). Total histone H3 and total histone H4 were used as loading controls for acetylated H3 and H4, respectively. g, h Nutlin-3 treatment rescued the cell proliferation phenotype of Fmr1 KO NPCs as measured by BrdU incorporation (g, red; scale bar, 20 µm) followed by quantitative analysis (h, n = 3). i, j Nutlin-3 treatment rescued neuronal differentiation phenotypes of Fmr1 KO NPCs as assessed by Tuj1⁺ staining (i, red; scale bar, 20 µm) followed by quantitative analysis (j, n = 3). k, l Acute knockdown of MDM2 rescued the cell proliferation phenotype of Fmr1 KO NPCs as assessed by incorporation of the thymidine analog, BrdU (l, red, BrdU; green, GFP, scale bar, 20 µm) and quantitative analysis (l, n = 3). m, n Acute knockdown of EP300 rescued neuronal differentiation phenotypes of Fmr1 KO NPCs as assessed by a neuronal marker Tuj1⁺ (m, red, Tuj1; green, GFP, scale bar, 20 µm) followed by quantitative analysis (n, n = 3). *P < 0.05, **P < 0.01, ***P < 0.001, n.s.: no significant difference. Two-way ANOVA was used for all data analyses. Data are presented as mean ± s.e.m.