Figure 6.

A 10 bp cassette of TH sequence from the 7/8 site is sufficient to cause arrest in one flanking sequence context. Templates were transcribed and size markers were generated (from the 7/8* template for the gel on the left and the NA2* template for the gel on the right) as described in Materials and Methods. In the lower part of the figure, sequences from the TH gene are underlined, distances downstream of +1 are given below the sequences and arrest positions are indicated by dots above the last nucleotide to be incorporated into the transcript.