Characterization of FGF23-Dependent Egr-1 Cistrome in the Mouse Renal Proximal Tubule
| Autor: | Martin Y. H. Zhang, Anthony A. Portale, Farzana Perwad, Valentin David, Yan Jiao, Weikuan Gu, Aline Martin |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Fibroblast growth factor 23
medicine.medical_specialty Hypophosphatemia MAP Kinase Signaling System lcsh:Medicine Mice Transgenic Sodium-Phosphate Cotransporter Proteins Type IIc Biology Fibroblast growth factor urologic and male genital diseases Sodium-Phosphate Cotransporter Proteins Type IIa Phosphates Kidney Tubules Proximal Mice Internal medicine Gene expression medicine Animals Vitamin D lcsh:Science Early Growth Response Protein 1 Regulation of gene expression Kidney Multidisciplinary lcsh:R body regions Fibroblast Growth Factors stomatognathic diseases Fibroblast Growth Factor-23 medicine.anatomical_structure Endocrinology Cistrome Gene Expression Regulation lcsh:Q Signal transduction Homeostasis hormones hormone substitutes and hormone antagonists Research Article |
| Zdroj: | PLoS ONE PLoS ONE, Vol 10, Iss 11, p e0142924 (2015) |
| ISSN: | 1932-6203 |
| Popis: | Fibroblast growth factor 23 (FGF23) is a potent regulator of phosphate (Pi) and vitamin D homeostasis. The transcription factor, early growth response 1 (egr-1), is a biomarker for FGF23-induced activation of the ERK1/2 signaling pathway. We have shown that ERK1/2 signaling blockade suppresses renal egr-1 gene expression and prevents FGF23-induced hypophosphatemia and 1,25-dihydroxyvitamin D (1,25(OH)2D) suppression in mice. To test whether egr-1 itself mediates these renal actions of FGF23, we administered FGF23 to egr-1 -/- and wild-type (WT) mice. In WT mice, FGF23 induced hypophosphatemia and suppressed expression of the renal Na/Pi cotransporters, Npt2a and Npt2c. In FGF23-treated egr-1 -/- mice, hypophosphatemic response was greatly blunted and Na/Pi cotransporter expression was not suppressed. In contrast, FGF23 induced equivalent suppression of serum 1,25(OH)2D concentrations by suppressing renal cyp27b1 and stimulating cyp24a1 mRNA expression in both groups of mice. Thus, downstream of receptor binding and ERK1/2 signaling, we can distinguish the effector pathway that mediates FGF23-dependent inhibition of Pi transport from the pathway that mediates inhibition of 1,25(OH)2D synthesis in the kidney. Furthermore, we demonstrate that the hypophosphatemic effect of FGF23 is significantly blunted in Hyp/egr-1 -/- mice; specifically, serum Pi concentrations and renal Npt2a and Npt2c mRNA expression are significantly higher in Hyp/egr-1 -/- mice than in Hyp mice. We then characterized the egr-1 cistrome in the kidney using ChIP-sequencing and demonstrate recruitment of egr-1 to regulatory DNA elements in proximity to several genes involved in Pi transport. Thus, our data demonstrate that the effect of FGF23 on Pi homeostasis is mediated, at least in part, by activation of egr-1. |
| Databáze: | OpenAIRE |
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