Cell-lineage specificity of primary cilia during epididymis post-natal development

Primary cilia are sensory organelles that orchestrate signaling pathways during organ development and homeostasis. By using a double Arl13b/mCherry-Cetn2/GFP transgenic mouse, we characterized the spatio-temporal localization of primary cilia in the epididymis, from birth to adulthood. We report here a constitutive localisation of primary cilia in myoid cells, and a dynamic profiling in epithelial cells throughout post-natal development. While primary cilia are present at the apical pole of undifferentiated epithelial cells from birth to puberty, they exclusively appear associated with cytokeratin 5-positive basal cells in adults. Exogenous labeling of primary cilia marker Arl13b and IFT88 confirmed the cell lineage specific localization of primary cilia in basal and myoid cells in human epididymides. From whole epididymis tissues and serum-free cultures of DC2 murine epididymal cell lines we determined that primary cilia from the epididymis are associated with the polycystic kidney disease-related proteins polycystin 1 and 2, and Gli3 Hedgehog signaling transcription factor. Thus, our findings unveil the existence of primary cilia sensory organelles, which have the potential to mediate mechano/chemo-signaling events in the epididymis.