The G215R mutation in the Cl-/H+-antiporter ClC-7 found in ADO II osteopetrosis does not abolish function but causes a severe trafficking defect
- Background: ClC-7 is a ubiquitous transporter which is broadly expressed in mammalian tissues. It is implied in the pathogenesis of lysosomal storage disease and osteopetrosis. Because of its endosomal/lysosomal localization it is still poorly characterized. Methodology/Principal Findings: An electrophysiological characterization of rat ClC-7 using solid-supported membrane-based electrophysiology is presented. The measured currents show the characteristics of ClC-7 and confirm its function as a Cl−/H+-antiporter. We have used rat ClC-7 in CHO cells as a model system to investigate the functionality and cellular localization of the wt transporter and its variant G213R ClC-7 which is the analogue of human G215R ClC-7 responsible for autosomal dominant osteopetrosis type II. Our study shows that rat G213R ClC-7 is functional but has a localization defect in CHO cells which prevents it from being correctly targeted to the lysosomal membrane. The electrophysiological assay is tested as a tool for drug discovery. The assay is validated with a number of drug candidates. It is shown that ClC-7 is inhibited by DIDS, NPPB and NS5818 at micromolar concentrations. Conclusions/Significance: It is suggested that the scenario found in the CHO model system also applies to the human transporter and that mislocalization rather than impaired functionality of G215R ClC-7 is the primary cause of the related autosomal dominant osteopetrosis type II. Furthermore, the robust solid-supported membrane-based electrophysiological assay is proposed for rapid screening for potential ClC-7 inhibitors which are discussed for treatment of osteoporosis.
Author: | Patrick Schulz, Johannes Werner, Tobias Stauber, Kim Henriksen, Klaus FendlerORCiDGND |
---|---|
URN: | urn:nbn:de:hebis:30-114747 |
DOI: | https://doi.org/10.1371/journal.pone.0012585 |
ISSN: | 1932-6203 |
Parent Title (English): | PLoS One |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2010/09/07 |
Date of first Publication: | 2010/09/07 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2011/09/07 |
Volume: | 5 |
Issue: | (9): e12585 |
Note: | Copyright: © 2010 Schulz et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
Source: | PLoS ONE 5(9): e12585. doi: 10.1371/journal.pone.0012585 |
HeBIS-PPN: | 276280628 |
Institutes: | Biochemie, Chemie und Pharmazie / Biochemie und Chemie |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie |
Sammlungen: | Universitätspublikationen |
Sammlung Biologie / Sondersammelgebiets-Volltexte | |
Licence (German): | Creative Commons - Namensnennung 3.0 |