Fig. 1

Oligodendrocytes express dystrophin glycoprotein complex (DGC) components and multiple dystrophin isoforms. a Immunocytochemistry on rat oligodendrocytes following 3 days of differentiation to detect selected DGC components (α-dystroglycan, β-dystroglycan, dystrophin, and utrophin), b western blot analysis dystrophin protein in skeletal muscle lysates (mdx/+ and mdx) and wildtype astrocyte lysates, c OPCs were cultured either in proliferation (prolif) or differentiation medium, then analyzed at days 1, 3 and 5 by western blot to detect dystrophin proteins. The positions of molecular weight standards are indicated. p115 immunoblots were used as loading controls. Three distinct dystrophin isoforms were detected: Dp427, Dp140, and Dp71, d the percentage of each dystrophin isoform, relative to the total dystrophin expressed at each time point, was calculated for oligodendrocytes at days 3 and 5, e schematic of oligodendrocyte maturation indicating at which maturation state particular dystrophin isoforms are upregulated, f the relative levels of dystrophin isoforms in OPCs (prolif) or oligodendrocytes at days 1, 3, and 5 in differentiating-promoting medium, g oligodendrocytes differentiated for 5 days (mature stage) were lysed and subjected to subcellular fractionation, followed by western blot analysis to detect dystrophin isoform proteins within the total cell, cytoplasmic, and nuclear fractions (soluble and insoluble). Dp427 and Dp140 were found in the cytoplasmic fraction, Dp140 was found in the soluble nuclear fraction, and Dp71 was found in the insoluble nuclear fraction. Cellular fractionation efficacy was verified with blotting for p115, which recognizes a vesicle docking protein that is cytoplasmic, and blotting for Lamin B1, a nuclear envelope protein, h confocal images of mature oligodendrocytes following dystrophin immunocytochemistry (green) reveal that dystrophin is distributed in the oligodendrocyte cell body, cell processes, and nucleus, i schematic depicting different pools of oligodendrocyte dystrophins