Insertion of structured RNA upstream of the IRES region does not affect IRES activity. (A) Time course of reporter translation efficiency in construct expressing the antisense sequence of the rnpB ribozyme upstream of the IRES region. Values correspond to the average of luciferase activity obtained from triplicate wells and performed in three independent assays. (B) Lack of inhibition of IRES-dependent translation by expression of the antisense sequence of rnpB. The luciferase activity determined at the indicated time in extracts of cells transfected with the asRz-IRES construct was normalized to the value observed in the IRES construct set to 100%. Error bars correspond to the standard deviation. (C) Expression of the antisense sequence of the rnpB gene does not induce RNA cleavage. RT-qPCR was used to determine the RNA amount corresponding to domains 3 and 4–5 of the IRES.
