Fig 6. Specific lack of Dp427 dystrophin isoform in Dmd^mdx rats central nervous system, but no modification of Dp140 and Dp71 levels.

WT controls (black dots, n = 4) and Dmd^mdx animals (grey dots, n = 4) were sacrificed and samples from brain areas (P: prefrontal cortex, A: amygdala, D: dorsal hippocampus, V: ventral hippocampus, C: cerebellum), spinal cord (SC), total brain (TB) with no specific targeted area and biceps femoris muscle from a WT rat (M), were harvested. Western-blot of total proteins was incubated with either monoclonal antibodies NCL-DYS2 and 30 μg protein loading for Dp71 and Dp140) or Manex1011C and 80 μg protein loading for Dp427 (A). Quantification on western-blot of dystrophin isoforms in each central nervous system region (n = 4 per genotype) were normalized to GAPDH levels, and then to dystrophin Dp427 control muscle levels (B, C). This revealed identical levels of 71 kDa (A, B) and 140 kDa (A, C) dystrophin isoforms in all studied central nervous system areas from WT and Dmd^mdx animals. Only Dp140 cerebellar levels were significantly higher compared to amygdalar levels in WT rats. Dp427 isoform was not detected in Dmd^mdx animals (A, D), and had variable levels in WT rats, with higher levels in cerebellum and spinal cord. Total WT brain extracts were used as positive controls for Dp71 and Dp140 detections, and biceps femoris muscle from a WT rat was used as positive control for Dp427 detection. Staining with an anti-GAPDH polyclonal antibody validated equal protein loadings. Data are expressed as mean ± SEM. In Fig 6C, *p < 0.05 vs. A. In Fig 6D, ****p < 0.0001 vs. SC, ^$ $ $p < 0.001 vs P, A, D and V and **p<0.01 vs. A and D.