Question

How does the DNA binding of a zinc finger–containing transcription factor differ from that of a prokaryotic repressor?

Short answer

The DNA binding of a zinc finger-containing transcription factor differs from that of a prokaryotic repressor because, unlike repressors, they use one or two zinc ions to stabilize the fold and the zinc fingers bind with two bases in the major groove of the DNA.

Step-by-step solution

Zinc Fingers

Zinc fingers are one of the early discovered eukaryotic DNA binding motifs. They use one or two zinc ions (Zn²⁺) to stabilize the structure of DNA.Each zinc finger is known to bind with the DNA in an identical manner that is through H-bonds between Zinc ions and two bases of the DNA in the major groove.

Prokaryotic repressor

Prokaryotic repressors regulate the gene expression by binding near or at the gene or the operator and stopping the transcription. They do not use zinc ions for stabilization nor bind through hydrogen bonds to the major groove of DNA.