Screen-based identification and validation of four new ion channels as regulators of renal ciliogenesis.

Abstract

To investigate the contribution of ion channels to ciliogenesis, we carried out a small interfering RNA (siRNA)-based reverse genetics screen of all ion channels in the mouse genome in murine inner medullary collecting duct kidney cells. This screen revealed four candidate ion channel genes: Kcnq1, Kcnj10, Kcnf1 and Clcn4. We show that these four ion channels localize to renal tubules, specifically to the base of primary cilia. We report that human KCNQ1 Long QT syndrome disease alleles regulate renal ciliogenesis; KCNQ1-p.R518X, -p.A178T and -p.K362R could not rescue ciliogenesis after Kcnq1-siRNA-mediated depletion in contrast to wild-type KCNQ1 and benign KCNQ1-p.R518Q, suggesting that the ion channel function of KCNQ1 regulates ciliogenesis. In contrast, we demonstrate that the ion channel function of KCNJ10 is independent of its effect on ciliogenesis. Our data suggest that these four ion channels regulate renal ciliogenesis through the periciliary diffusion barrier or the ciliary pocket, with potential implication as genetic contributors to ciliopathy pathophysiology. The new functional roles of a subset of ion channels provide new insights into the disease pathogenesis of channelopathies, which might suggest future therapeutic approaches.

• Authors: Gisela G Slaats, Gabrielle Wheway, Veronica Foletto, Katarzyna Szymanska, Bas W M van Balkom, Ive Logister, Krista Den Ouden, Mandy G Keijzer-Veen, Marc R Lilien, Nine V Knoers, Colin A Johnson, Rachel H Giles
• Journal: Journal of cell science (J Cell Sci) Vol. 128 Issue 24 Pg. 4550-9 (Dec 15 2015) ISSN: 1477-9137 [Electronic] England
• PMID: 26546361 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015. Published by The Company of Biologists Ltd.

Chemical References

• Potassium Channels
• RNA, Small Interfering

Topics

• Animals
• Cell Line
• Cilia (genetics, metabolism)
• Humans
• Kidney Tubules, Collecting (metabolism, pathology)
• Mice
• Potassium Channels (genetics, metabolism)
• RNA, Small Interfering (genetics, pharmacology)