The HNF-3/Fork head protein is depicted in the right-hand corner of Geis’ painting, bound to a separate strand of DNA than the other proteins are. Notice how the protein interacts with different grooves of the DNA strand.
Used with permission from the Howard Hughes Medical Institute (www.hhmi.org). All rights reserved.
Related PDB Entry: 1VTN
Experimental Structure Citation
Clark, K. L., Halay, E. D., Lai, E., & Burley, S. K. (1993). Co-crystal structure of the HNF-3/fork head DNA-recognition motif resembles histone H5. Nature, 364, 412-420.
The HNF-3/Fork head protein is a transcription factor that binds to a highly conserved DNA sequence, present in various organisms ranging from yeast to humans. HNF-3 binds as a monomer to B-DNA through interactions with its backbone and bases in both major and minor grooves, creating a 13-degree bend in DNA as it binds. The HNF-3 protein resembles the structure of histone H5.