SLC6A14, an amino acid transporter, modifies the primary CF defect in fluid secretion
- University of Toronto, Canada
- Hospital for Sick Children, Canada
Abstract
The severity of intestinal disease associated with Cystic Fibrosis (CF) is variable in the patient population and this variability is partially conferred by the influence of modifier genes. Genome-wide association studies have identified SLC6A14, an electrogenic amino acid transporter, as a genetic modifier of CF-associated meconium ileus. The purpose of the current work was to determine the biological role of Slc6a14, by disrupting its expression in CF mice bearing the major mutation, F508del. We found that disruption of Slc6a14 worsened the intestinal fluid secretion defect characteristic of these mice. In vitro studies of mouse intestinal organoids revealed that exacerbation of the primary defect was associated with reduced arginine uptake across the apical membrane, with aberrant nitric oxide and cyclic GMP mediated regulation of the major CF-causing mutant protein. Together, these studies highlight the role of this apical transporter in modifying cellular nitric oxide levels, residual function of the major CF mutant and potentially, its promise as a therapeutic target.
Data availability
All of the data is presented in the submitted figures (in the article file) and supplementary file
Article and author information
Author details
Funding
Canadian Institutes of Health Research (CIHR MOP-97954,CIHR GPG-102171)
- Fan Lin
Cystic Fibrosis Canada (CFC-1)
- Christine Bear
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: SickKids Animal Approval: #1000037433
Copyright
© 2018, Ahmadi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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SLC6A14, an amino acid transporter, modifies the primary CF defect in fluid secretion
eLife 7:e37963.
https://doi.org/10.7554/eLife.37963
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