PAR-CLIP analysis of miRNAs and tRFs. (A) Read counts for miRNAs, tRF-5s, tRF-3s and tRF-1s in AGO 1 to 4 PAR-CLIP data from Hafner et al. Each microRNA and tRF is given an identifying number. The expression level of each microRNA and tRF is shown on the Y-axis and the assigned number is shown on the X-axis. (B) Normalized positional T to C mutation frequencies for miRNA, tRF-5 and tRF-3 reads found in the AGO 1 to 4 PAR-CLIP data. (C) Matches of canonical and noncanonical seeds of the 50 most abundant miRNAs, tRF-5s or tRF-3s seen in the AGO1 dataset to the 17,319 CCRs reported in Hafner et al.