Nontemplated 3′-end nucleotides in oocyte microRNAs. (A) Proportion of microRNAs with nontemplate 3′-end nucleotide addition in oocytes and developmental small RNA libraries of T. castaneum and Drosophila. (B) Length distribution of nontemplate 3′-end nucleotide additions. (C) Sequence logos showing the most frequent nucleotides in the first five positions of the 3′-end nontemplated nucleotide additions in the three species. (D) Scatter plots showing the proportion of reads with nontemplate 3′-end additions as a function of the total read counts (modified and nonmodified) per million for each microRNA. Results of different replicates for each species are shown separately. Example singleton microRNAs or microRNAs from clusters that are conservatively deposited in the egg are highlighted in orange, and highly deposited and strongly modified microRNAs specific for a given species are highlighted in purple.
