DNA response elements

DNA response elements are generally found a short distance upstream of promoters in selected genes. They are specific for selective transcription factors and... 

The yeast reporter gene assays not only assess for the interaction of the chemical with the hormone receptor, but also the ability of that receptor-chemical ligand interaction to activate the hormone DNA response element. It should be realized, however, that most of these systems have been developed with human and mammalian hormone receptors and differences in ligand potencies can occur between different animal species. A comprehensive review of in vitro assays for measuring estrogenic activity, and some of the issues of comparability, is provided by Zacharewski (1997). 

Peroxisome proliferator-activated receptors (PPARs) are transcription factors that bind to DNA response elements (PPREs) and control multiple aspects of lipid metabolism. Individual members of this family of zinc-finger proteins are activated by a variety of natural and xenobiotic dgands, including ... 

Geseiick C, Meyer HA, Haendler B. (2005) The role of DNA response elements as allosteric modulators of steroid receptor function. Mol Cell Endocrinol. 236,1-7. 

Zhang J., Saleh D. S. and Wyatt G. R. (1996) Juvenile hormone regulation of an insect gene a specific transcription factor and a DNA response element. Mol. Cel. Endocrin. 122, 15-20. 

Ability to Bind Specific DNA Response Elements. No polymorphisms currently known that affect this function. 

The PPAR-RXR complex binds to specific DNA response elements (PPREs composed of two hexanucleotide direct repeats) in gene promoters and functions as a transcription factor, which can be activated by either RXR- or PPAR-specific ligands. The consensus site for PPAR-RXR binding is a direct repeat of two -AGGTCA- sequences with a single nucleotide spacer (a DR1 response element). However, DR1 elements may also bind other complexes, including RAR (retinoic acid receptor)/RXR heterodimers and RXR homodimers (25). Further specificity for binding of PPARs may be provided by sequences that flank the DR1 site (26). 

A notable feature of retinoic acid nuclear receptors is that their DBDs and LBDs can communicate with each other retinoic acid receptors bound to DNA response elements modulate ligand binding through a kind of feedback mechanism. This allows fine tuning of ligand-dependent transcriptional activity. 

Figure 3 The PPAR family and its DNA properties, (a) The murine PPAR subfamily. The DNA and ligand-binding domains are indicated. Numbers represent percentage amino acid identity, (b) The PPARs bind to DR-1-type DNA response elements as heterodimers with RXR. The PPAR/RXR heterodimer can be activated by ligands for either PPAR or RXR. (Reproduced from Kliewer SA, Xu HE, Lambert MH, and Willson TM (2001) Peroxisome proliferator-activated receptors From genes to physiology. Recent Progress in Hormone Research 56 239-265, with permission from The Endocrine Society.)...

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