The activity of the highly inducible mouse phenylalanine hydroxylase gene promoter is dependent upon a tissue-specific, hormone-inducible enhancer.

Expression of the phenylalanine hydroxylase gene in livers and kidneys of rodents is activated at birth and is induced by glucocorticoids and cyclic AMP in the liver. Regulatory elements in a 10-kb fragment upstream of the mouse gene have been characterized. The promoter lacks TAATA and CCAAT consensus sequences and shows only extremely weak activity in transitory expression assays with phenylalanine hydroxylase-producing hepatoma cells. No key elements for regulation of promoter activity are localized within 2 kb of upstream sequences. However, a liver-specific DNase I-hypersensitive site at kb -3.5 comprises a tissue-specific and hormone-inducible enhancer. This enhancer contains multiple protein binding sites, including sites for ubiquitous factors (NF1 and AP1), the glucocorticoid receptor, and the hepatocyte-enriched transcription factors hepatocyte nuclear factor 1 (HNF1) and C/EBP. Mutation revealed that the last two sites are critical not only for basal activity but also for obtaining a maximal hormone response. Efficient transcription from the highly inducible promoter shows absolute dependence upon the enhancer at kb - 3.5, which in turn requires HNF1 and C/EBP as well as hormones. The regulatory region of the mouse phenylalanine hydroxylase gene differs totally from that of humans, even though the genes of both species are expressed essentially in the liver. Furthermore, the phenylalanine hydroxylase gene of mice shows an expression pattern very similar to those of the rodent tyrosine aminotransferase and phosphoenolpyruvate carboxykinase genes, yet each shows a different organization of its regulatory region.
AuthorsD M Faust, A M Catherin, S Barbaux, L Belkadi, T Imaizumi-Scherrer, M C Weiss
JournalMolecular and cellular biology (Mol Cell Biol) Vol. 16 Issue 6 Pg. 3125-37 (Jun 1996) ISSN: 0270-7306 [Print] UNITED STATES
PMID8649424 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • DNA Probes
  • Transcription Factors
  • Dexamethasone
  • DNA
  • Cyclic AMP
  • Phenylalanine Hydroxylase
  • Deoxyribonuclease I
  • Animals
  • Base Sequence
  • Binding Sites
  • Cell Line
  • Cyclic AMP (pharmacology)
  • DNA (genetics, metabolism)
  • DNA Probes (genetics)
  • Deoxyribonuclease I
  • Dexamethasone (pharmacology)
  • Enhancer Elements, Genetic (drug effects)
  • Gene Expression Regulation, Enzymologic
  • Humans
  • Kidney (enzymology)
  • Liver (enzymology)
  • Mice
  • Molecular Sequence Data
  • Organ Specificity
  • Phenylalanine Hydroxylase (genetics)
  • Promoter Regions, Genetic
  • Rats
  • Transcription Factors (metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: