Question

Describe the functions of the two independent domains of eukaryotic activator

Answer 1

Eukaryotic activator is a DNA binding protein that stimulates the transcription initiation. Some activators recognize the upstream promoter elements and influence transcription initiation only at the promoter to which these elements are attached.

In general, activator have been found to consist of two domains: One region of the protein specifically binds DNA known as DNA binding domains (DBD) and other region of the activator protein is called activation domain (AD), this domain activates the transcription by interacting with other components of the transcriptional machinery.

The basic function of DBD is to anchor the transcription factor to the proper site on DNA; the activation domain (AD) then independently stimulates transcription by interacting with other proteins.

Some common types of activation domains are acidic domains, glutamine and proline rich domains.

DNA binding domain (DBD) of the activator proteins possess the DNA binding motifs that permits specific binding of activator to its target.

Some conserved DNA structural motifs are; the leucine zipper, helix-loop-helix, helix turn helix and zinger finger motifs.