Supplementary Figure 3: H–PGDS^–/– are normally myelinated.

a) Representative immunofluorescence of two months old s–type, L–PGDS^–/– and H–PGDS^–/– sciatic nerve cross sections stained for H–PGDS (rhodamine). H–PDGS is expressed in wild–type and in L–PGDS^–/– in similar amounts. Sections were also stained for neurofilament (fluorescein) and nuclei (DAPI). Lack of signal in H–PGDS^–/– confirmed antibody specificity. N = 3 independent experiments. Bar: 50 μm. b–d) Morphological analyses of 1 month wild–type and H–PGDS^–/– sciatic nerves. b) Electron micrographs and c) g–ratio analyses confirmed normal myelination in H–PGDS^–/–. g–ratio as a function of axon diameter is similar in wild–type (red line) and H–PGDS^–/– (black line) (t–test analysis; P = 0.4261; t=0.7964, df=662). The graph represents the g–ratio obtained from more than 250 myelinated axons. d) Distribution of myelinated fibers is similar in H–PGDS^–/– and wild–type 1 month sciatic nerves. Fisher’s exact test; P = 0.4449 (total vs 1–2 μm), P = 0.5546 (total vs 2–3 μm), P = 0.2521 (total vs 3–4 μm), P = 0.1694 (total vs 4–5 μm), P = 1 (total vs 5–6 μm). Over 80 fibers for each genotype were counted. N = 3 mice per genotype. Bar: 2 μm. e–g) Morphological analyses of 6 month wild–type and H–PGDS^–/– sciatic nerves. e) Electron micrographs and f) g–ratio analyses confirmed normal myelination in H–PGDS^–/–. g–ratio as a function of axon diameter is similar in wild–type (red line) and H–PGDS^–/– (black line) (t–test analysis; P = 0.6071; t=0.5725, df=388). The graph represents the g–ratio obtained from more than 150 myelinated axons. g) Distribution of myelinated fibers is similar in H–PGDS^–/– and wild–type 6 month sciatic nerves. Fisher’s exact test; P = 0.2325 (total vs 1–2 μm), P = 0.8385 (total vs 2–3 μm), P = 0.811 (total vs 3–4 μm), P = 0.1056 (total vs 4–5 μm), P = 0.4431 (total vs 5–6 μm), P = 1 (total vs 6–7 μm), P = 0.2243 (total vs 7–8 μm), P = 1 (total vs >8 μm). Over 60 fibers for each genotype were counted. N = 3 mice per genotype. Bar: 2 μm.