Alterations in renal cilium length during transient complete ureteral obstruction in the mouse

The renal cilium is a non-motile sensory organelle that has been implicated in the control of epithelial phenotype in the kidney. The contribution of renal cilium defects to cystic kidney disease has been the subject of intense study. However, very little is known of the behaviour of this organelle during renal injury and repair. Here we investigate the distribution and dimensions of renal cilia in a mouse model of unilateral ureteral obstruction and reversal of ureteral obstruction. An approximate doubling in the length of renal cilia was observed throughout the nephron and collecting duct of the kidney after 10 days of unilateral ureteral obstruction. A normalization of cilium length was observed during the resolution of renal injury that occurs following the release of ureteral obstruction. Thus variations in the length of the renal cilium appear to be a previously unappreciated indicator of the status of renal injury and repair. Furthermore, increased cilium length following renal injury has implications for the specification of epithelial phenotype during repair of the renal tubule and duct.