Figure 11. Post-transcriptional regulation of PTH mRNA stability by calcium, phosphorus, and chronic renal failure. Pre-pro-PTH gene expression is modulated via changes in protein-PTH mRNA interactions at the 3′-UTR region which determine PTH mRNA stability. Low calcium diet increases stability, whereas low phosphate diet decreases stability of PTH mRNA. The PTH mRNA 3’-untranslated region-binding protein was subsequently identified as AUF1.