Transactivation domain

In biochemistry, the transactivation domain is the subregion ( domain) of a transcription factor that is responsible for the transcriptional activation of DNA. The stimulation of transcription is achieved by the binding of specialized proteins, especially basal transcription factors and RNA polymerase.

The function of a transcription factor - the activation or deactivation of genes - can be subdivided into different subfunctions that are reflected in the structure of the protein. In addition to the transactivation domain, frequently encountered domains include, for example, a dimerisation domain for binding to other proteins and a DNA-binding domain for binding to regulatory regions of the DNA. If the transactivation domain of a transcription factor is removed in the course of a protein design, the resulting recombinant protein inhibits transcription: with the aid of the DNA binding domain, it is able to bind to DNA, but transcription is not activated. This results in competition between the recombinant protein and any wild-type protein present for the limited number of specific DNA-binding sites.

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