FIG. 1.

RT-PCR in the ORF50 gene region of rpOka, rpOkaORF50AS(−), and rpOkaORF50AS(−)Rev-infected MeWo cells and identification of novel transcripts from the ORF50 gene region. RNAs were extracted when full CPE was observed in each sample of virus-infected MeWo cells. RT-PCRs were carried out using a specific primer set for the ORF50 gene (lanes 2, 4, and 6), and PCRs without RT were carried out as a control for contamination with genomic DNA (lanes 1, 3, and 5). Molecular mass markers are shown at the left. White circles at the right of lane 2 indicate the spliced transcripts. The experiments were done twice independently, and one of them is shown here.