FIG. 5.

Addition of false ATG codons with a strong context (black bars) into the upstream area of the E1 ORF. These codons are expected to stop scanning ribosomes. Two codons that are shown in lane 8, on pEPI, are two existing strong ATG codons within the E7 ORF. The striped area represents the 12-amino-acid epitope that was added for detection of E7 levels. The numbers in the last column are those of the nucleotides that were mutated to create strong ATGG initiation codons. The numbering is according to reference 5.