FIG. 1.

Schematic depiction of the linearized HPV31 genome. (Top) Upstream regulatory region located between the late and the early regions. Numbered boxes represent BS1 through -4, and the binding site for E1 is shown as an oval. The start sites for the early promoter P97 and the late P742 promoter are indicated by arrows. Open reading frames (ORFs) are shown in black. (Bottom) Mutated E2BS in mutant genomes are shown as crossed squares. The positions of translational stop codons introduced into the E1 and E2 genes are indicated by arrows.