FIGURE 2.

Toeprint analysis of capped and uncapped RNA. The sequence ladder indicates the AUG start codon. Primer extension of the β-globin RNA (full extension) and toeprint are indicated on the right. Presence (+) or absence (−) of an m⁷G cap on the RNA is indicated at the top of the gel. Lanes 3 and 4 (80S) denote reactions in the presence of cycloheximide; lanes 5 and 6 (48S) denote reactions in the presence of GMP-PNP. The fraction toeprint, indicated in the bar graph, represents the fraction of cpm at +14 to +18 compared with cpm for full extension. The values shown are the average, and the error bars indicate the standard deviation of multiple independent experiments.