title: 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.affiliation: Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Gisela G
authors.initials: GG
authors.lastname: Slaats
authors.affiliation: Section of Ophthalmology and Neuroscience, Leeds Institutes of Molecular Medicine, University of Leeds, Leeds LS9 7TF, UK.
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Wheway
authors.affiliation: Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Veronica
authors.initials: V
authors.lastname: Foletto
authors.affiliation: Section of Ophthalmology and Neuroscience, Leeds Institutes of Molecular Medicine, University of Leeds, Leeds LS9 7TF, UK.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Szymanska
authors.affiliation: Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Bas W M
authors.initials: BW
authors.lastname: van Balkom
authors.affiliation: Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Ive
authors.initials: I
authors.lastname: Logister
authors.affiliation: Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Krista
authors.initials: K
authors.lastname: Den Ouden
authors.affiliation: Department of Pediatric Nephrology, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Mandy G
authors.initials: MG
authors.lastname: Keijzer-Veen
authors.affiliation: Department of Pediatric Nephrology, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Marc R
authors.initials: MR
authors.lastname: Lilien
authors.affiliation: Department of Medical Genetics, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands.
authors.forename: Nine V
authors.initials: NV
authors.lastname: Knoers
authors.affiliation: Section of Ophthalmology and Neuroscience, Leeds Institutes of Molecular Medicine, University of Leeds, Leeds LS9 7TF, UK.
authors.forename: Colin A
authors.initials: CA
authors.lastname: Johnson
authors.affiliation: Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands r.giles@umcutrecht.nl.
authors.forename: Rachel H
authors.initials: RH
authors.lastname: Giles
mesh_terms: D000818:Animals; D002460:Cell Line; D002923:Cilia / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007685:Kidney Tubules, Collecting / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000494:pharmacology
chemical_list: D015221:Potassium Channels; D034741:RNA, Small Interfering
keywords: CLCN4; Cilia; KCNF1; KCNJ10; KCNQ1; Patient mutation; siRNA screen