Primary cilia in the basal cells of equine epididymis: a serendipitous finding.

The research article is about the unexpected discovery of primary cilia in the basal cells of the epididymal epithelium in equidae, including horses, donkeys, and mules, and suggests that this organelle might play a role in monitoring luminal factors and extracellular liquids, acting as a chemical receptor of the luminal environment.

Key Findings

• The researchers unexpectedly found primary cilia in the basal cells of the epididymal epithelium in all individuals of the equines studied, regardless of their age or the part of the duct they were in. This is a novel and surprising observation in epididymal epithelium research.
• The primary cilia emerged from the basal cell surface and insinuated into the intercellular spaces. Occasionally, solitary cilia also occurred at the luminal surface of the principal cells.

Structure of the Ciliary Apparatus

• The ciliary apparatus was structured with a basal body, which is typical and continuous with the finger-like ciliary shaft that extends from the cell surface. It also had an adjacent centriole that was oriented at right angles to the basal body.
• The defined structure of the cilium was found to be that of primary, non-motile cilia, with a 9+0 microtubular pattern that is commonly seen in many mammalian cells.
• The basal diplosome was randomly associated with other cellular organelles, including the Golgi complex, the endoplasmic reticulum, the microfilament network, the plasma membrane, vesicles, and pits.

Possible Roles of the Primary Cilia

• The researchers suggest that the primary cilia might have a functions related to monitoring luminal factors and extracellular liquids, therefore acting as a chemical receptor of the luminal environment.
• In this possible role, the primary cilia could be modulating the epididymal epithelial function by facilitating a cell-to-cell crosstalk that involves the entire epithelium.