Solution structure of the POU-specific DNA-binding domain of Oct-1

Nuclear magnetic resonance was used to determine the solution structure of the POU-specific DNA-binding domain of transcription factor Oct-1. Four alpha-helices are connected by short loops with helices I and IV in a parallel coiled-coil arrangement. There is an apparent similarity between the folding topology and that of the bacteriophage lambda-repressor and 434 repressor. Helix III appears to be the mediator in DNA-binding. A model for the POU-DNA complex is presented.