Fig. 3: Ddx3x regulates the formation and development of dendritic spines.
From: Sex-specific perturbations of neuronal development caused by mutations in the autism risk gene DDX3X
A Experimental design. Cortical neurons are isolated from Ddx3x+/+, Ddx3x+/flox, Ddx3xflox/flox, Ddx3x+/y, or Ddx3xflox/y E15 embryos. At DIV9, neurons are transfected with the construct carrying mCherry and CRE, resulting in sparsely labeled Ddx3x+/+ (black), Ddx3x+/- (purple), Ddx3x-/- (pink), Ddx3x+/y (gray), or Ddx3x-/y (yellow) neurons. Analyses are performed at DIV14. Created in BioRender103. B Ddx3x dosage influences dendritic spine density. Confocal images of 10 μm dendritic segments 50 μm distant from the soma, showing mCherry-expressing dendritic shafts and spines. Scale bar, 1 μm. C Ddx3x loss in female (but not male) neurons alters spine density. The plot shows the number of dendritic spines in 10 μm. D Dendritic density varies as a function of the distance from the soma. The plot shows the number of dendritic spines in 10 μm as a function of distance from soma (values on the X axis represent the upper boundary of the segment, e.g., 50 μm marks the 40-50 μm segment). E Ddx3x haploinsufficiency alters the balance of spine subtypes. The plot shows the proportion of dendritic spines across the six spine subtypes, defined as indicated in the Methods section (n spines above each bar). F, G Ddx3x haploinsufficiency results in increased spine neck length, as shown by the average spine neck length (F) and the empirical cumulative distribution function of the spine neck length measures (G). H, I Ddx3x haploinsufficiency results in increased spine head width, as in F, G but for the spine head width. Statistics: Panel C, one-way ANOVA, followed by Student’s t test with Benjamini-Hochberg correction; Panel D, repeated measure ANOVA, followed by Tukey test with Benjamini-Hochberg correction at 60-70 μm segments. Panel E, Chi-square test. Panels F and H, Kruskal-Wallis test, followed by Wilcoxon test with Benjamini-Hochberg correction. Panel G and I, Kolmogorov–Smirnov test. In all panels, data were collected blind to genotype and sex; n is shown in legend as number of neurons (and number of embryos); mean ± SEM; outliers shown as ⊗; *P-value < 0.05, **P-value < 0.01, ***P-value < 0.001. Source data are provided as a Source Data file.
