Sphingosine rescues the glial bulging phenotype.

<p>(A) Addition of sphingosine to diet rescues the <i>lace</i> phenotype. Arrowheads indicate glial swelling region. (B) Orthogonal projections showed that dietary addition of sphingosine rescues the enwrapment defect. (C) Quantification of average cross-section area after knockdown of <i>lace</i> in glia and upon sphingosine treatment is shown. All graphs represent mean values ± SD. One-way ANOVA followed by Tukey <i>post hoc</i> test was performed for statistical analysis. Scale 20 µm (D1–D3) TEM micrographs of L3 larval peripheral nerve cross-sections are shown. Wrapping glia is color-coded. Vacuoles (blue arrowhead) are present in the wrapping glia and there is loss of membrane extension resulting in lack of proper ensheathement in <i>repo-GAL4</i>/<i>lace</i> RNAi flies as compared to control <i>repo-GAL4/+</i> flies. (D3) Addition of 300 µM sphingosine to the diet (Matreya, USA) rescues the ensheathment defect. (E) Quantification of the number of unwrapped axons before and after sphingosine treatment in the in <i>lace</i> knocked down flies. (repo-GAL4/laceRNAi). One-way ANOVA followed by Tukey <i>post hoc</i> test was performed. All graphs represent mean values ±SD. *** p<0.001.