Fig. 3.

Electron microscopic visualization of mitochondrial pathology in human and murine desminopathies. a Granulofilamentous material (gfm), subsarcolemmal accumulation of mitochondria (ma), and multiple enlarged mitochondria (arrowheads) in skeletal muscle tissue from a German patient harboring a heterozygous E245D/D214_E245del (c.735G>C) desmin mutation [14]. b Upper panel normal mitochondria regularly positioned adjacent to myofibrillar Z-discs in murine wild-type (WT) soleus muscle. Middle panel aged heterozygous (HET) R349P desmin knock-in mice occasionally displayed focal accumulation (ma) of normal and enlarged mitochondria. Lower panel homozygous (HOM) mice, the left image illustrates the depletion of mitochondria in a large sarcoplasmic area comprising normal myofibrils and myofibrillar remnants. The right image depicts focal mitochondrial accumulation (ma) and enlarged mitochondria (arrowheads) in the intermyofibrillar space