Activator (genetics)

An activator is a DNA-binding protein that regulates one or more genes by increasing the rate of transcription. The activator may increase transcription by virtue of a connected domain which assists in the formation of the RNA polymerase holoenzyme, or may operate through a coactivator. A coactivator binds the DNA-binding activator and contains the domain assisting holoenzyme formation. A particular activator may bind one or more specific coactivators.
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