FIG. 5.

RT-nested-PCR analysis of HPV31b spliced E4 transcripts expressed following infection of HaCaT cells. Details of the experiment are given in the legend to Fig. 3. (A) Primers E6A and E4.3B were used in the first round, primers E6.2A and E4B were used in nested PCR. (B) Primers E7.4A and E4.3B were used in the first round, primers 742A and E4B were used in nested PCR. For each reaction, the input RNA in the first round of PCR corresponded to 1.9 μg. (C) Early region of the HPV31b genome and explanation of observed RNA structures as described in the legend to Fig. 1 and 3C. Boldface letters denote previously characterized ORFs, with their splice junctions indicated in parentheses. The novel RNA structures containing the 210∧3332 and the 877∧3332 splice junctions are indicated. The novel 210∧3332 spliced structure was verified by sequencing from at least one of the samples in panel A and the 877∧3332 splice junction was determined from multiple positive samples as shown in panel B.