Figure 1.

Conservation of the let-7 microRNA. (A) Sequence conservation of let-7 microRNA. (B) Phylogenetic tree of Caenorhabditis species based on phylogeny from Stevens et al. (2020). For each species, the makeup of their let-7-family microRNAs is indicated. let-7-family microRNAs are predicted from their genomic sequences (brown font), detection in previous studies (magenta font), or detection in this study (blue font). Green branches highlight species that are either predicted or confirmed to have let-7. Red branches highlight species that are either predicted or confirmed to lack let-7. Outlined in the green box are species recovered in the Elegans group. Outlined in the red boxes are species recovered in the Japonica group. Branch lengths are proportional to substitutions per site. Scale bar is shown.