FIG. 6.

Localization of TBP binding in vaccinia virus intermediate I1L and late I2L promoters. Panels A and B show sequences of oligonucleotides used for the DNA binding assays of the I1L and I2L promoters, respectively. The oligonucleotides contain native promoter elements (uppercase nucleotides) and nonnative ends (lowercase nucleotides). Letters and numbers to the left of each oligonucleotide correspond to the panel and lane numbers in the gels shown below each. The positions of C nucleotide replacements are indicated. Numbers above each sequence indicate nucleotide positions relative to the start site for transcription. Recombinant TBP was incubated with oligonucleotides containing the core and initiator elements of the I1L promoter (panels C and D, respectively) and the core and initiator elements of the I2L promoter (panels E and F, respectively). Binding mixtures were subjected to electrophoresis on a polyacrylamide gel to resolve protein-DNA complexes, indicated by arrows. Odd-numbered lanes are oligonucleotide alone, and even-numbered lanes are oligonucleotides incubated with TBP. Asterisks indicate the top of the gel.