Frequency-stability relationships for natural TLRs. (A) A more stable tertiary interaction could lead to a higher fraction folded of the host RNA, in turn leading to greater fitness and prevalence in biology. (B) The (log) frequency of TLR variants across different host RNAs has a (significantly) negative correlation with the stability of the RNA. (C–H) The frequency-stability correlation is stronger in some host RNA contexts and nonexistent in others. Stability is represented as the average ΔΔG from the 11ntR in 30 mM Mg2+ taken from Bonilla et al. (2021). The three TLRs highlighted in this work are denoted by colored points: blue for the 11ntR, red for the IC3R, and orange for Vc2R. Dashed gray lines plot the log-linear fit between frequency and stability. Significant negative correlations are signified with an asterisk.
