Potential targeting of frequent ORF repeats by additional miRNAs. (A) Motifs frequently repeated in ORFs of many mRNAs. The histogram considers all 65,536 possible 8-nt motifs and plots the number of these 8mers that match the indicated number of unique ORF at least four times. Also indicated are the seven miRNAs with 8mer sites among the 334 motifs that appeared at least four times in at least 25 genes. (B) The amino acid sequence coded by regions flanking 8mer ORF sites corresponding to the miRNA indicated. Sites overlap codons 7–9. Letter size indicates enrichment, visualized using WebLogo (weblogo.berkeley.edu). (C) Locations of 8mer sites within the repeated C2H2 domain. (D) Locations of C2H2 domains and miR-181 sites within the RBAK gene. Two C2H2 domains in which one of the histidines has been lost are shown as noncanonical zinc fingers. In cases where a single zinc finger contains both 8mer and 7mer sites, the 7mer overlaps the second cysteine in the motif.
