Axonal degeneration in paraplegin-deficient mice is associated with abnormal mitochondria and impairment of axonal transport
J. Clin. Invest. Fatima Ferreirinha, et al. 113:231 doi:10.1172/JCI20138 [Go to this article.]

Figure 5
Mitochondrial abnormalities in paraplegin-deficient mice. (a) The spinal cord has an overall normal structure in a 4.5-month-old Spg7–/– mouse, but high magnification analysis shows hypertrophic mitochondria (b), sometimes with swollen, disorganized cristae (arrow) (c). Several mitochondrial abnormalities are identifiable in the spinal cord at 8 months of age: swollen mitochondria with cristae still readily identifiable (asterisk), onion-like arrangement of mitochondrial cristae (arrows) (d), gigantic mitochondrion with abnormally organized membrane compartments and abnormal tubular content (e), closely associated mitochondria (f), and swollen mitochondria in which cristae are displaced at the periphery of the organelle (g). (h) Spinal axon of a 12-month-old Spg7–/– mouse containing degenerating mitochondria. (i) At 15 months of age, mitochondria are swollen and show degenerative features. There is a drastic reduction in the number of cristae, which are distended. The deposition of dense deposits can be observed. Mitochondrial bridges are also evident (arrow). (j) Transverse section of the optic nerve of 22-month-old paraplegin-deficient mouse showing one hypertrophic mitochondrion extending a finger-like protrusion (mitochondrial “bridge”; arrow) into a neighboring mitochondrion, which shows features of swelling and degeneration. Bar represents 5 μm in a, 0.8 μm in b, c, f, g, and j, and 1 μm in d, e, h, and i.