Figure 3.

Sequences of constructs tested and quantification of transcriptional arrest. Initially transcribed sequences (ITS) from +1 to the start of the 50 bp TH inserted fragments are shown at the top of the lists of pML20-42- and pML23-100-based constructs. Sequences from the TH gene are underlined and positions where arrest occurred are marked by dots. The major arrest positions are listed on the right for each template, followed by the fraction of complexes that arrested at each position. The percentage arrest was calculated as described in Materials and Methods and for most templates is the average of several reactions.