Referenced in: none

Automatically associated channels: ClC4 , ClC5

Title: Disordered calcium crystal handling in antisense CLC-5-treated collecting duct cells.

Authors: John A Sayer, Georgina Carr, Simon H S Pearce, Timothy H J Goodship, Nicholas L Simmons

Journal, date & volume: Biochem. Biophys. Res. Commun., 2003 Jan 10 , 300, 305-10

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12504084

Abstract
Dent's disease, an X-linked tubulopathy secondary to defects in chloride channel CLC-5, is characterised by low molecular weight proteinuria, hypercalciuria, nephrocalcinosis, and renal stones. Mechanisms leading to nephrocalcinosis are unknown. Using a murine collecting duct cell line (mIMCD-3), we confirm endogenous expression of mCLC-5. During transfection of antisense CLC-5, we observe a reduction in CLC-5 protein expression that correlates with a reduction in the number of acidic endosomal compartments, as determined by quantitative analysis of confocal microscope images using LysoTracker Red. Using wheat germ agglutinin-lectin as an endocytic marker, an arrest of endocytosis is observed in antisense CLC-5 treated cells. Exposure of the cell surface to calcium oxalate crystals results in crystal agglomeration in a minority of sense CLC-5 transfectants (45%) and all antisense CLC-5 transfectants. We conclude that expression of CLC-5 in mIMCD-3 cells allows acidification of endosomes and endocytosis, and that disruption of CLC-5 expression causes abnormal crystal agglomeration.