In vitro transcription analysis. In vitro transcription analysis was performed for the complete upstream sequences of genes 14 and 19 in forward and reverse orientations ligated to a partial lacZ gene segment (301 bp) (solid black boxes). The orientation of ligated promoter regions is shown by arrowhead lines (right arrowhead line, forward orientation; left arrowhead line, reverse orientation). Wiggled arrowhead lines show predicted transcripts of 335 bases for gene 14 and 327 bases for gene 19. Sequence segments and the predicted transcripts for genes 14 and 19 are shown as cartoons on the left, and the observed transcripts are shown on the right of the panels. Puc18 plasmid DNA was used as the template to generate a sequence ladder with an M13 forward primer. Numbers 1 and 2 refer to the constructs for in vitro transcription for gene 14, and 3 and 4 refer to in vitro transcription templates for gene 19.