A Global In Vivo Drosophila RNAi Screen Identifies a Key Role of Ceramide Phosphoethanolamine for Glial Ensheathment of Axons
(A, B) Quantification of total glial cell number (mean±SD) upon lace knockdown in glia. Counting the number of glial nuclei in A8 peripheral nerve (n = 8) revealed no significant differences between control and lace RNAi larva. (C) Double immunolabeling of anti-β-galactosidase (red) and anti-repo (green) of lace5 (LacZ enhancer trap line) in L3 larval peripheral nerves. Colocalization shows that lace is expressed in glial cells, present in the peripheral abdominal nerves. (D) RT-PCR analysis showed that lace is expressed in the nervous system of both males and female flies. (E) Hypomorphic combination of lace mutant (lace2/lace5) showed axonal defasciculation and increase in the cross-section area of the nerve (arrows). HRP (red) and mCD8-GFP (green) were used to visualize the neuronal and glial morphology, respectively. (F) Quantification showed that the expression of UAS-lace by repo-GAL4 could rescue the mutant phenotype. Scale bar 20 µm. All graphs represent mean values ± SD. Unpaired t-test (two groups) and One-way ANOVA followed by Tukey post hoc test (for three groups) were performed for the statistical analysis. Scale 20 µm. ** p<0.01 *** p<0.001. ns not significant.