Fig. 5

Localization of sHSPs and HSP90 in myofibers of additional human myopathies and mouse models. (a) Sarcomeric I-band association of αB-crystallin (αBC), HSP27 and HSP90 in human HMERF-titinopathy (TTN), MFM-myotilinopathy (MYOT), IBMPFD due to mutations in VCP, and DMD, by indirect immunofluorescence (secondary antibodies: FITC-conjugated IgG or Cy3-conjugated IgG). In human MFM-desminopathy (DES) only HSP90 was I-band-associated, whereas the two sHSPs were found mainly in cytosolic aggregates. In sporadic inclusion body myositis (sIBM), the chaperones were detected in the cytosol and at the Z-disc (as in CTRL muscles). Note that in healthy CTRL myofibers (not shown here), the chaperones were always at the Z-disc and in the cytosol and usually did not show the doublet banding pattern typical for most myopathies. For additional immunostainings on these human samples, and counterstaining with anti-titin, see Additional file 1: Figure S4. (b) Sarcomeric I-band association of αB-crystallin, HSP27 and HSP90 in mouse models of MFM-filaminopathy (FLNC) and Duchenne muscular dystrophy (MDX), as well as normal CTRL muscles, by indirect immunofluorescence (secondary antibodies: FITC-conjugated IgG) and nanogold-labeling immuno-EM. CTRL and MDX myofibers were also immunostained against methyltransferase Smyd2 (co-chaperone of HSP90). For additional immunostainings on these mouse samples, and counterstaining with anti-titin, see Additional file 1: Figure S5. Bars, 5 μm (confocal images) and 1 μm (EM)