Figure 3.

Oligos and pyrophosphate affect the his and ops pause complexes differently. (A) The pause half-lives are plotted (as a fraction of a “no-oligo” control) by the 3′-most nucleotide of the nascent RNA that remains outside the RNA:oligo duplex (equivalent to the 5′-terminal base of the 22-nt oligonucleotides). Each value is an average of at least two independent measurements. (B) Immobilized TECs were halted along the templates encoding the his (Left) or ops (Right) pause signals at the positions indicated below each panel and treated with increasing concentrations of PP_i (0, 0.001, 0.01, 0.1, and 1 mM) as described previously (16).