Related Experiment Video
Updated: Aug 7, 2026

Atomic Force Microscopy Investigations of DNA Lesion Recognition in Nucleotide Excision Repair
Published on: May 24, 2017
The X-ray structure of the GCN4-bZIP bound to ATF/CREB site DNA shows the complex depends on DNA flexibility
1Institut für Molekularbiologie und Biophysik ETH-Höngerberg, Zürich, Switzerland.
Abstract:
The X-ray structure of the DNA binding domain of the yeast transcriptional activator protein GCN4 bound to a DNA fragment containing the sequence of the perfectly symmetrical ATF/CREB site has been solved to 3.0 A resolution. The architecture of this specific recognition complex supports the current model for bZIP proteins: a homodimer of parallel alpha-helices form an interhelix coiled-coil region via the leucine zipper, and the two N-terminal basic regions fit into the major groove of half sites on opposite sides of the DNA double helix. The structure shows that DNA flexibility plays the predominant role in the preservation of protein contacts with the symmetric ATF/CREB site (ATGACGTCAT) as compared to the pseudo-symmetric AP-1 target site (ATGACTCAT), overcoming the positional displacement of functional groups introduced by the additional G.C base-pair at the center of the ATF/CREB sequence.
Related Concept Videos
Nucleosome Remodeling
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
DNA Helicases
DNA Topoisomerases
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
Cooperative Binding of Transcription Regulators
Single-Strand DNA Binding Proteins
Cooperative Binding of Transcription Regulators

