FIG. 8.

Organization of the DBD regions of SV40 large T antigen and BPV E1. The DBD domains of each protein are shaded, and the ATPase regions are striped. Within the DBDs, the open rectangles labeled A and B2 for T antigen and HR1 and HR2 for E1 indicate the locations of sequence regions critical for DNA binding activity (see text for details). The double-headed arrows between the open rectangles represent the similar spacing of approximately 50 amino acids in both proteins. Numbers refer to amino acids of each protein.