Effect of individual RNA aptamers from the Es8, Fs10, and Gs12 cohorts on cognate SMD activity. Activity of SMD-Ll1 and SMD-Ll2 in the presence of RNA aptamers found in cohorts Es8 (top, Ll1), Fs10 (middle, Ll1), and Gs12 (bottom, Ll2) at SMD:RNA molar ratios of 1:10 was calculated from fluorescence measurements. SMD activity is expressed as percent of the fluorescence counts obtained with each protein in the absence of RNA (black bars). Data shown are averages of three experiments (n = 3), each in triplicate, ± SEM. The inhibitory effects of the RNA pools of origin are shown in hatched bars. The dots (•) in each bar represent the number of clones that were found to have the same sequence as that specific clone. Clones belonging to families are shown in white bars and orphan clones are shown in grey. Significant inhibitions relative to protein alone were determined by an ANOVA of repeated measures and the Tukey post-test (*** P < 0.001, ** P < 0.01, * P < 0.05).