FIG. 5.

Competition by VAI RNA against PKR-RNA gel shift complexes. Labeled RNAs (ca. 0.2 ng or about 0.1 nM [final concentration]) were preincubated with 250 nM PKR [K296R] for 5 min and then incubated for an additional 15 min with different concentrations of unlabeled VAI RNA (2.5 nM [lanes 2, 7, and 12], 25 nM [lanes 3, 8, and 13], 250 nM [lanes 4, 9, and 14], and 2.5 mM [lanes 5, 10, and 15]) or without VAI RNA competitor (−; lanes 1, 6, and 11). Mobility shift complexes were analyzed on 5% nondenaturing polyacrylamide gels. The positions of wells (W), free probe (F), and complexes (C) are indicated. The mobilities of the three probes in the absence of PKR were examined in separate control experiments.