Fig. 10.

Ceramide associates with Arl13b, which is critical for complex formation with acetylated tubulin in motile cilia of ependymal cells. A, B: The PLA detecting Arl13b-acetylated tubulin complexes (red) and immunocytochemistry for Arl13b (blue) and acetylated tubulin (green) shows that reduction of ceramide levels with FB1 disrupts complex formation and ciliogenesis in primary cultured mouse ependymal cells (arrows). C: Ependymal cells were metabolically labeled with PAz and S-palmitoylation visualized by click chemistry–mediated addition of fluorophore (Cy5). The PLA was performed using antibodies against ceramide and Arl13b showing that S-palmitoylation (blue) is at least partially colocalized with ceramide-acetylated tubulin complexes (red, arrows). Ceramide immunolabeling is shown in green. FB1, fumonisin B1; PAz, palmitic azide; PLA, proximity ligation assay.