The Transcription Map of Human Papillomavirus Type 18 during Genome Replication in U2OS Cells
Figure 4
Mapping of the HPV18 transcription polyadenylation cleavage sites (CSs) by 3′ RACE.
The assays were conducted in U2OS cells that were transiently transfected with the HPV18 genome (timepoints are indicated above each gel) and in HPV18-positive U2OS subclone #1.13 cells that were cultured in subconfluent or confluent conditions. (A) 3′ RACE analysis of the HPV18 early region CS with the HPV18-specific primer Pr3976. The 3′ RACE product (indicated by an arrow) represents the CS at 4270. (B) 3′ RACE analysis of the HPV 18 late region CS with the HPV18-specific primer Pr7020. Three 3′ RACE products (marked as 1, 2 and 3 and indicated by arrows) represent the CSs at nt 448, nt 7693 and nt 7298, respectively. (C) 3′ RACE analysis with the HPV18-specific primer Pr2500 for analysis of the CSs of E1-encoding transcripts. Three 3′ RACE products (marked as 1, 2 and 3 and indicated by arrows) represent the CSs at nt 4270, nt 3339 and nt 2741, respectively.