What Enhancers Contain Bidirectional Elements That Assist Initiation? what the role of a receptor?

-An enhancer activates the promoter nearest to itself and can be any distance either upstream or downstream of the promoter as well as form complexes of activators that interact directly or indirectly with the promoter. -creating an upstream activating sequence (UAS) in yeast behaves like an enhancer, but works only upstream of the promoter. the repressor – A protein that inhibits expression of a gene. It may act to prevent transcription by binding to an enhancer or silencer.