The conditional NTE knock-out results in incomplete glial wrapping of Remak fibers. (A, C) Electron microscopic image from a Remak bundle in a TAM treated NTE(+/+);Cre+ mouse. (B, D) Remak bundle in a TAM-treated NTE(fl/fl);Cre+ mouse. The arrowheads point to areas where the glial sheath is missing, arrows point to electron dense, shrunken axons. (D) Quantification showing the percentage of axons in a Remak bundle that are not completely wrapped by glia. The horizontal line represents the medians, boxes denote the 25% and 75% quartiles, and whiskers express 10% and 90% quantiles. Twenty Remak bundles were analyzed per genotype, with two mice used for each experiment. Scale bar=500 nm. ***p < 0.0001 (Student’s t-test).