Figure 5

Figure 5

Transmission electron microscopy analysis of the skeletal muscle of the WT and sgcd^−/− adult zebrafish lines. Ultrathin sections from 1-year-old WT zebrafish (A–D) and age-matched sgcd^−/− zebrafish (E–L). Scale bar: um, µm. It is possible to observe that in some regions, the contractile tissue and mitochondria (M) of the mutant fish (panel (E,F)) were almost indistinguishable from the wild type (panels (A–D)). On the other hand, in most of the sections of sgcd^−/− (panels (G–L)), clear signs of myopathy were present such as myofibrillar fragmentation (white arrowheads), fiber damage (white arrows), out-of-frame sarcomeric array (panel (J)), hypercontracted fibers (red arrows), and dilated sarcoplasmic reticulum (SR). In these regions, mitochondria are degenerating (panels (H,K), red arrowheads).