Fig. 3.

Axonal and neuronal degeneration and muscle pathology in lister mutant mice. (A and B) Toluidine blue staining of white matter of spinal cord from wild-type and lister/lister, respectively. Arrowhead indicates a degenerating axon. (C and D) TEM images of distal femoral nerve branches of wild-type and lister mutants, respectively. (E and F) H&E staining of hind-leg quadriceps skeletal muscles from wild-type and lister/lister animals, respectively. Arrow indicates a centrally nucleated muscle fiber. (G) Comparison of number of motor neurons >25 μm in diameter in lumbar spinal cord between +/+ (black bars, n = 5) and lister/lister (gray bars, n = 7) mice at symptom onset (P = 0.639) and terminal stage (P < 0.05). (H) Number of axons counted from cross sections of motor and sensory L5 roots in lister/lister and wild-type littermates at different stages (n = 3–5 each genotype per age group). +/+ versus lister/lister mice at symptom onset for motor root (P = 0.741) and sensory root (P = 0.135), at terminal stage for motor root (P < 0.05) and sensory root (P < 0.01). (I and J) Distribution of axon diameters from the entire motor and sensory roots of terminal-staged lister/lister (gray circles) versus +/+ (black circles).