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Updated: Jun 1, 2026
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Functional Reconstitution and Channel Activity Measurements of Purified Wildtype and Mutant CFTR Protein
Published on: March 9, 2015
Segmental and subcellular distribution of CFTR in the kidney
François Jouret1, Pierre J Courtoy, Olivier Devuyst
1Division of Nephrology, Université Catholique de Louvain Medical School, B-1200, Brussels, Belgium.
Methods in Molecular Biology (Clifton, N.J.)
|May 20, 2011
Summary
The cystic fibrosis transmembrane conductance regulator (CFTR) is found in kidney endosomes, aiding in protein reabsorption. This protein
Area of Science:
- Cell Biology
- Renal Physiology
- Molecular Biology
Background:
- The cystic fibrosis transmembrane conductance regulator (CFTR) is primarily known for its role in ion transport across epithelial cells.
- CFTR is also found in intracellular vesicles, suggesting roles beyond the plasma membrane.
Purpose of the Study:
- To investigate the subcellular localization and function of CFTR in mouse kidney proximal tubule (PT) cells.
- To determine if CFTR participates in receptor-mediated endocytosis of low molecular weight (LMW) proteins in the kidney.
Main Methods:
- Immunostaining and subcellular fractionation of mouse kidneys.
- Co-localization studies with endosomal markers (megalin, cubilin, V-ATPase, ClC-5, Rab5a).
- Deglycosylation studies and immunoblotting to analyze CFTR glycosylation.
Main Results:
- CFTR is localized in endosomes of PT cells, co-distributing with megalin and cubilin.
- CFTR co-localizes with V-ATPase and early endosome markers, including ClC-5 and Rab5a.
- CFTR exhibits a distinct glycosylation pattern in the kidney compared to the lung.
Conclusions:
- CFTR's presence in PT endosomes supports its role in receptor-mediated endocytosis.
- CFTR may contribute to endosomal acidification, facilitating the uptake of filtered LMW proteins by PT cells.
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