Fig. 4. Mat1-deficient Schwann cells attain a mature myelinated phenotype. (A) Toluidine blue staining of osmicated, plastic embedded sciatic nerve cross sections (1 µm) from control and mutant animals at approximately 1 month (P37) and 2 months (P67) of age. (B) Delayed onset demyelination of Mat1-deficient myelinated Schwann cells. Histopathology of mutant animals at 3 months (P97) and 5 months (P157) of age. Arrowheads point to examples of remyelinating Schwann cell/axon units; arrows point to examples of denuded large diameter axons; and the asterisk points to myelin debris.