...ON. When a repressor binds the activator protein, the activator protein cannot bind the promoter sequence... cannot bind the promoter sequence and transcription is ON. Once a co-repressor protein binds the repressor...derivatives is added, it binds tTA, resulting in a confirmation change that prevents binding to the promoter and...cumate is added, it binds cTA, resulting in a confirmation change that prevents binding to the promoter and.... As ethanol accumulates, it binds to the repressor, enabling it to bind the promoter and repress pADH1...system). The GAL80 repressor can bind to GAL4, partially inhibiting the binding of GAL4 to UAS. One can therefore...manner, with LexA binding to the lexA operator (lexAop). Fusing the LexA DNA-binding domain (DBD) to GAL4...