Figure 1
From: Chondroitin Sulfate Is Required for Onset and Offset of Critical Period Plasticity in Visual Cortex
T1 deletion inhibits CS biosynthesis. (A,B) Expression of T1 mRNA in mouse V1 (A) during postnatal development (B, mean and SEM; critical period (CP, P28–P30) versus adulthood (AD, >P60), p = 0.02, ANOVA). Dark-rearing (DR) enhances the expression (p = 0.007, ANOVA), and genetic T1 deletion (KO) removes it completely (p = 0.0002, ANOVA). II/III, VI, and V indicate the cortical layers; Wm, white matter. The scale bar represents 200 μm. (C) Reduction of the total CS amount in the adult V1 of T1 KO mice (mean ± SEM [pmol/mg]; WT 2134.4 ± 123.2 versus KO 1169.5 ± 52.9, four mice, p = 0.002, t-test). (D–I) Decreased expression of aggrecan in V1 of T1 KO mice. WFA labeling or aggrecan immunoreaction in the binocular zone was decreased in adult T1 KO (E,G) compared to WT mice (D,F). Quantitative analysis of the number of WFA-labeled cells (H, 600 × 350 μm area; WT 34.4 ± 2.4, KO 24.3 ± 1.2 for P28–30; WT 41.3 ± 1.3, KO 35.3 ± 1.3 for >P60; 3–4 mice, P28–P30 versus >P60, p < 0.0001 for WT, p < 0.05 for KO, ANOVA), and WFA-labeled or aggrecan immunofluorescence intensity in the adult V1 (I, WFA; three mice, p = 0.0008, t-test, aggrecan; three mice, p = 0.016, t-test). (J) Expression of CSPGs in the adult V1. Western blotting analyses verified reduction of aggrecan in T1 KO mice (six mice, p = 0.005, t-test) and no significant difference in the protein quantity of other CSPGs between genotypes (six mice, p > 0.05, t-test). The full-length blots are shown in a Supplementary Information.
