Fig. 6.

Increasing Mecp2 levels leads to improvement in Tcf4^+/− pyramidal cell morphology.

Mice were treated as described in Fig. 5. (A–C) Representative images of dendrites from pyramidal cells from p120 Tcf4^+/+, Tcf4^+/− and Tcf4^+/−scAAV9.P546.MeCP2-injected mice. When compared to the WT group, both treated and untreated Tcf4^+/− samples showed significant reductions in dendritic length (upper panel, A to C, Scale bar: 50 ​μm), the number of the dendritic spines, and overall spine density (boxes in the lower panel, A’ to C’; Scale bar: 5 ​μm) compared to control. These observations were consistent for both basal and apical dendrites. Quantification of dendritic length (D–F), number of dendritic spines (G–I), and overall spine density (J–L) was performed using Neurolucida (MBF Bioscience, VT). Importantly, treatment with AAV9.MECP2 significantly improved total dendrite length, spine counts and spine density overall and in both basal and apical dendrites. Statistical analysis was performed using One-way ANOVA with Tukey post-hoc analysis comparing the mean of each data set to the combined average of the controls (dotted line). ∗p ​< ​0.05, ∗∗p ​< ​0.01, ∗∗∗p ​< ​0.001, ∗∗∗∗p ​< ​0.0001.