FIG. 1.

Transcription in the absence of ATP. (A) Schematic drawing of the template pIC-31/2. The nucleotide sequence of the promoter region and the region around the transcription start site (+1) is shown. In the absence of ATP, synthesis of a 6-nt RNA product (+6) was expected. (B) Transcription reaction mixtures contained RNA polymerase, 4 μM UTP, 20 μM CTP, and template pIC-31/2. The presence (+) or absence (−) of aTBP, TFB, and GTP (20 μM) in the reaction mixture is indicated. For size calibration of the RNA product, the ATP analogue 3′-dATP was added to allow incorporation of the next nucleotide (lane C).