In vitro termination is dependent on functional poly(A) signals. (A) Time-course of in vitro transcription reactions with wild-type extracts and templates carrying wild-type CYC1, mutant cyc1-512, or no terminator sequences (Δterm) as indicated. (B) Quantification of the gels shown in A. The obtained signals were normalized to uridine content of the cassettes and presented as a percentage of G-less transcription. Transcriptional elongation efficiency is indicated by the 100/84 ratio. Termination and 3′ end formation is reflected by the 120/100, 131/100, and 145/100 signals. (C) Presentation of the 40-min time point of the time-course experiments shown in A as a function of the distance of G-less transcription relative to the site of poly(A) addition, which has been fixed at “0” bp. The signal obtained with the 100-bp cassette was fixed at 100%; the 120/100, 131/100, and 145/100 ratios provide the other data points.
