First Author | Han X | Year | 2016 |
Journal | PLoS One | Volume | 11 |
Issue | 2 | Pages | e0147845 |
PubMed ID | 26839958 | Mgi Jnum | J:248880 |
Mgi Id | MGI:6093215 | Doi | 10.1371/journal.pone.0147845 |
Citation | Han X, et al. (2016) Conditional Deletion of Fgfr1 in the Proximal and Distal Tubule Identifies Distinct Roles in Phosphate and Calcium Transport. PLoS One 11(2):e0147845 |
abstractText | A postnatal role of fibroblast growth factor receptor-1 (FGFR1) in the kidney is suggested by its binding to alpha-Klotho to form an obligate receptor for the hormone fibroblast growth factor-23 (FGF-23). FGFR1 is expressed in both the proximal and distal renal tubular segments, but its tubular specific functions are unclear. In this study, we crossed Fgfr1flox/flox mice with either gamma-glutamyltransferase-Cre (gammaGT-Cre) or kidney specific-Cre (Ksp-Cre) mice to selectively create proximal tubule (PT) and distal tubule (DT) Fgfr1 conditional knockout mice (designated Fgfr1PT-cKO and Fgfr1DT-cKO, respectively). Fgfr1PT-cKO mice exhibited an increase in sodium-dependent phosphate co-transporter expression, hyperphosphatemia, and refractoriness to the phosphaturic actions of FGF-23, consistent with a direct role of FGFR1 in mediating the proximal tubular phosphate responses to FGF-23. In contrast, Fgfr1DT-cKO mice unexpectedly developed hypercalciuria, secondary elevations of parathyroid hormone (PTH), hypophosphatemia and enhanced urinary phosphate excretion. Fgfr1PT-cKO mice also developed a curly tail/spina bifida-like skeletal phenotype, whereas Fgfr1DT-cKO mice developed renal tubular micro-calcifications and reductions in cortical bone thickness. Thus, FGFR1 has dual functions to directly regulate proximal and distal tubule phosphate and calcium reabsorption, indicating a physiological role of FGFR1 signaling in both phosphate and calcium homeostasis. |