Features of response elements:
1. can be located in a promoter or an enhancer sequence
2. have no fixed location, rather they are usually within 200 bp upstream of the transcription start site (most are located within 1 kb of the tss).
3. a single element is usually sufficient to confer a regulatory response
4. contain short consensus sequences
5. modules are related but not identical
6. it is assumed that a specific protein factor (trans-acting) binds to the element, and that the presence of that protein is developmentally regulated
For example, the cAMP response element (CRE) interacts with the transcription factor CREB (CRE-binding protein), which is regulated by cAMP. The consensus sequence for CRE is TGACGTCA.
Receptors for steroid hormones act as transcription factors for hormone response elements, such as ERE, GRE, TRE & T3RE
ERE : GRE : HSE : SRE : TRE : T3RE