Fig. 4.

Aptamers in different classes affect preinitiation complex assembly in mechanistically distinct ways. Factors bound to the immobilized template were quantified after washing by Western blot analysis with antibodies to TATA-binding protein (TBP), TFIIA, TFIIB, and TFIIE, and a representative blot is shown beneath each graph. (A) The effects of low concentrations of AptTBP-12 and AptTBP-101 on TFIIA and TFIIB association with template. (B) Effects of aptamers on the four general transcription factors at aptamer concentrations that produce saturating or near saturating inhibitory effects. Graphs shown are representative of three independent experiments, and standard errors are shown. Each data set has been normalized to the no-aptamer data point.