REPLICATIVE INTERMEDIATES OF HUMAN PAPILLOMAVIRUS TYPE-11 IN LARYNGEAL PAPILLOMAS - SITE OF REPLICATION INITIATION AND DIRECTION OF REPLICATION

We have examined the structures of replication intermediates from the human papillomavirus type 11 genome in DNA extracted from papilloma le sions (laryngeal papillomas). The sites of replication initiation and termination utilized in vivo were mapped by using neutral/neutral and neutral/alkaline two-dimensional agarose gel electrophoresis methods. Initiation of replication was detected in or very close to the upstrea m regulatory region (URR; the noncoding, regulatory sequences upstream of the open reading frames in the papillomavirus genome). We also sho w that replication forks proceed bidirectionally from the origin and c onverge 180 degrees opposite the URR. These results demonstrate the fe asibility of analysis of replication of viral genomes directly from in fected tissue.