Regulation of ClC-K/barttin by endocytosis influences distal convoluted tubule hyperplasia.

Autor: Mayayo-Vallverdú C; Genes, Disease and Therapy Program, Molecular Genetics Laboratory-IDIBELL, Genetics Section, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain., Gaitán-Peñas H; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain.; Centro de Investigación en red de enfermedades raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain., Armand-Ugon M; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain., Muhaisen A; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain., Prat E; Genes, Disease and Therapy Program, Molecular Genetics Laboratory-IDIBELL, Genetics Section, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain., Castellanos A; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain.; Centro de Investigación en red de enfermedades raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain., Elorza-Vidal X; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain.; Centro de Investigación en red de enfermedades raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain., de Heredia ML; Genes, Disease and Therapy Program, Molecular Genetics Laboratory-IDIBELL, Genetics Section, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.; Centro de Investigación en red de enfermedades raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain., Alonso-Gardón M; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain., Pérez-Rius C; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain., Vecino-Pérez M; Genes, Disease and Therapy Program, Molecular Genetics Laboratory-IDIBELL, Genetics Section, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain., Mallen A; Department of Nephrology, Hospital Universitart Bellvitge and Institut d'Investigació Biomèdica de Bellvitge-IDIBELL, L'Hospitalet de Llobregat, Spain., Errasti-Murugarren E; Genes, Disease and Therapy Program, Molecular Genetics Laboratory-IDIBELL, Genetics Section, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain., Hueso M; Department of Nephrology, Hospital Universitart Bellvitge and Institut d'Investigació Biomèdica de Bellvitge-IDIBELL, L'Hospitalet de Llobregat, Spain., Artuch R; Centro de Investigación en red de enfermedades raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.; Institut de Recerca Sant Joan de Déu, Barcelona, Spain., Nunes V; Genes, Disease and Therapy Program, Molecular Genetics Laboratory-IDIBELL, Genetics Section, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.; Centro de Investigación en red de enfermedades raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain., Estévez R; Physiology Unit, Department of Physiological Sciences, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Spain.; Genes, Disease and Therapy Program, Physiology and pathology of the functional relationship between glia and neurons-IDIBELL, L'Hospitalet de Llobregat, Spain.; Centro de Investigación en red de enfermedades raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.
Jazyk: angličtina
Zdroj: The Journal of physiology [J Physiol] 2024 Sep; Vol. 602 (17), pp. 4291-4307. Date of Electronic Publication: 2024 Aug 06.
DOI: 10.1113/JP286729
Abstrakt: ClC-K/barttin channels are involved in the transepithelial transport of chloride in the kidney and inner ear. Their physiological role is crucial in humans because mutations in CLCNKB or BSND, encoding ClC-Kb and barttin, cause Bartter's syndrome types III and IV, respectively. In vitro experiments have shown that an amino acid change in a proline-tyrosine motif in the C-terminus of barttin stimulates ClC-K currents. The molecular mechanism of this enhancement and whether this potentiation has any in vivo relevance remains unknown. We performed electrophysiological and biochemical experiments in Xenopus oocytes and kidney cells co-expressing ClC-K and barttin constructs. We demonstrated that barttin possesses a YxxØ motif and, when mutated, increases ClC-K plasma membrane stability, resulting in larger currents. To address the impact of mutating this motif in kidney physiology, we generated a knock-in mouse. Comparing wild-type (WT) and knock-in mice under a standard diet, we could not observe any difference in ClC-K and barttin protein levels or localization, either in urinary or plasma parameters. However, under a high-sodium low-potassium diet, known to induce hyperplasia of distal convoluted tubules, knock-in mice exhibit reduced hyperplasia compared to WT mice. In summary, our in vitro and in vivo studies demonstrate that the previously identified PY motif is indeed an endocytic YxxØ motif in which mutations cause a gain of function of the channel. KEY POINTS: It is revealed by mutagenesis and functional experiments that a previously identified proline-tyrosine motif regulating ClC-K plasma membrane levels is indeed an endocytic YxxØ motif. Biochemical characterization of mutants in the YxxØ motif in Xenopus oocytes and human embryonic kidney cells indicates that mutants showed increased plasma membrane levels as a result of an increased stability, resulting in higher function of ClC-K channels. Mutation of this motif does not affect barttin protein expression and subcellular localization in vivo. Knock-in mice with a mutation in this motif, under conditions of a high-sodium low-potassium diet, exhibit less hyperplasia in the distal convoluted tubule than wild-type animals, indicating a gain of function of the channel in vivo.
(© 2024 The Author(s). The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)
Databáze: MEDLINE
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