Figure 7. Organization of the nodal region and cleft numbers in 4.1B mutants.

A. EMs of sciatic nerve fibers from wild type and 4.1B^−/− mice highlighting the longitudinal organization of the nodal regions are shown; scale bar, 4 μm. B. High power images through the optic nerve showing the organization of the paranodes demonstrate preservation of the close apposition of the paranodal loops and the presence of transverse bands in wild type (top) and 4.1B^−/− (bottom) optic nerves; scale bar, 200 nm. C. Quantitation of the numbers of Schmidt-Lanterman incisures as a function of internode length. 4.1B^−/− mutant nerves have approximately twice as many incisures per unit of length as do wt mice