Fig. 4

TRIM32 mutant myoblasts show impaired differentiation. a-c When primary myoblasts from family A patients (n = 2), family B patients (n = 2), healthy controls (n = 6) and disease controls (2 LGMD2B, X-EDMD) (n = 3) reached confluence, proliferation medium was replaced with differentiation medium and the myoblasts started to fuse into myotubes, which were analyzed after 4 days of differentiation. a Immunofluorescence showing double staining of primary myoblasts, desmin (red) and myogenin (green). Nuclei were counterstained with Topro 3 (blue). b The expression of myogenin and c the fusion index were reduced in TRIM32^V591M and TRIM32^{N217S/F568del} myoblasts compared with controls. Data from 10 to 32 independent fields were analyzed per condition. Mean ± SEM; Kruskal-Wallis with Dunn’s multiple comparisons test. Scale bar, 50 μm. d Western blot analysis of biceps muscle lysates derived from family A patients, family C patient and healthy controls. Myosin heavy chain and myogenin antibodies show reduced expression in TRIM32^V591M and TRIM32^C39LfsX17 muscles compared with controls. An anti-GAPDH blot is included as a loading control