(A) Diagram of the circular dsHPV16 genome (gray circle). Other HPV genomes are very similar in organization. Viral ORFs are indicated with colored arcs above the genome. Promoters are indicated with P and chevrons (P97, P670, PE8). Early (pAE) and late (pALs) polyadenylation sites are indicated with short straight lines above the circular genome. The LCR is indicated with a blue line. (B) Details of the LCR sometimes called the URR. The E6 ORF is shown as an open rectangle. The end of the L1 ORF is shown as a partial open rectangle. The early promoter (P97) is indicated with and arrowhead. The proximal promoter region is indicated with a double arrowhead red line. Four E2 binding sites in the LCR are indicated with green squares. The origin of replication (ori) to which E1 binds is shown as a purple circle. The late polyadenylation site is indicated by Poly(A)L and a straight line. The late regulatory element that controls late gene expression is indicated with a blue box. Locations of the different features are not to scale.