Figure 7

Northern blot of wildtype and mutant U6 promoter activity. Plasmid DNA with the wildtype (wt) and mutant U6 promoters transcriptionally regulating the aptamer 70.15 were transfected into 293T cells. After 48 hours, total RNA was isolated, separated by electrophoresis, blotted and probed for expression of the aptamer 70.15 and of the U6 snRNA (endogenous control). Shown are 3 replicates for the aptamer and the U6 snRNA. The intensity of each band (x10⁴ units) was quantified with the STORM 820 phosphorimager and is shown below the image. A relative ratio of the aptamer 70.15 signal to the endogenous U6 snRNA expression is shown. The fold decrease of mutant U6 promoter activity and Wt U6 promoter activity in regulating transcription of the aptamer 70.15 is indicated below the line for each replicate. The reduction in expression of the mutant U6 promoter was 0.50 ± 0.12 fold (mean ± standard deviation [SD]).