Fig. 6.

Microtubule depolymerization does not affect the localization of FILIP1 at Z-discs and in sarcomeric lesions. a–a''''', b–b''''' Immunolocalization of FLNc and total tubulin (beta-tub) in C2C12 myotubes treated with (a–a''''') DMSO or (b–b''''') 4 μg/ml nocodazole (NZ). NZ treatment for 2 h induced complete depolymerization of the microtubule network, which was rescued within 2 h after washout of NZ, after the EPS treatment. c–c''''''' Representative images of C2C12 myotubes treated with EPS and DMSO or NZ and stained for FLNc, FILIP1 and total tubulin (beta-tub). The localization of FILIP1 at the Z-discs (indicated by arrowheads) and in sarcomeric lesions (indicated by arrows) is not affected by the treatment with NZ. d–d''''' Representative images of C2C12 myotubes pre-incubated for 2 h with DMSO (d) or NZ (d'), subsequently treated with twitch EPS for 1 h to induce sarcomeric lesions (d''–d'''), and rescued by a 2 h incubation with medium without DMSO or NZ (d''''–d'''''). Myotubes were stained for FLNc. The arrows indicate EPS-induced lesions. Note that treatment with NZ seems to reduce the number of lesions induced by EPS. e Histogram showing the number of sarcomeric lesions (expressed as # of lesions/$\mu$m²) induced by the indicated different experimental conditions used in (d–d'''''). Twitch EPS significantly increased the number of lesions, but not in myotubes treated with NZ. Data are expressed as mean ± S.E.M. 9–18 cells were analysed for each experimental condition. Significance was assessed using the Kruskal–Wallis test and the post hoc Dunn's multiple comparisons test. **p < 0.01; ***p < 0.001