Figure 4.

Four-month-old qv^3J mice have dramatic changes in axon shape and cytoskeletal organization. A, B, Transverse optic nerve sections from WT (A) and qv^3J (B) mice show that qv^3J mouse axons are highly convoluted and not cylindrical. C, D, Longitudinal and transverse (inset) cross sections show that, compared with WT mice (C), qv^3J mice have a dramatic increase in the density of cytoskeletal elements (D). Nodes of Ranvier are delineated by arrows. E, F, High magnification of optic nerve cross sections shows qv^3J mice (F, arrow) have an increased density of neurofilaments compared with WT mice (E). G, Immunoblotting for neurofilament proteins shows that, in contrast to NF-L and NF-H, the amount of NF-M is increased in qv^3J mutant mice. The same blots were probed for α-tubulin as a control for protein loading. Scale bars: A, B, 3 μm; C, D, 1 μm; inset, 0.5 μm; E, F, 0.25 μm.