Figure 5
From: Three-dimensional ultrastructure of giant mitochondria in human non-alcoholic fatty liver disease
The 3-D structure of intramitochondrial crystalline inclusions (ICIs) and enlarged matrix granules revealed by transmission electron tomography. (A) High-magnification image (15,000× magnification) of longitudinal arrays of ICIs (arrowheads) and enlarged matrix granules (arrows) distributed throughout the mitochondrial matrix. (B) 3-D model view of the outer- (dark blue) and inner mitochondrial membranes (red), ICIs (light blue) and enlarged matrix granules (orange), corresponding to (A). (C) Higher-magnification model view of a bundle of ICIs corresponding to the yellow bounding box in (B). (D) High-magnification image (30,000× magnification) and corresponding model view (E) of a bundle of ICIs in transverse section. The individual rod-like filaments appear to be composed of globular subunits, measuring 8.65 ± 1.31 nm in diameter and are arranged in a rhomboid pattern with regular periodicities of 7.38 ± 1.61 nm. (F) Rotated model view relative to (E) indicating the rod-like inclusions are organised as individual filaments, and not lamellar sheets as may be perceived from 2-D TEM micrographs. (G) Schematic diagram revealing the internal ultrastructure of giant mitochondria. The left-hand side of the diagram reveals a 2-D image of common ultrastructural abnormalities within the matrix of giant mitochondria, such as ICIs enlarged matrix granules and disrupted cristae. The right-hand side of the diagram reveals characteristic features of giant mitochondria that may not be observed in their entirety in a single image, or a single magnification, including: mitochondrial DNA, ribosomes, matrix granules, the inner- and outer mitochondrial membranes and intervening intermembrane space, as well as ICIs in both longitudinal and transverse profile. Scale bars: (A & B) 200 nm; (C–F) = 50 nm.
