Small RNAs from Miwi2P-asDnmt3L in fetal testes. (A) Numbers of small RNAs annotated as from the Miwi2P-asDnmt3L transgene among total reads in the testes of nontransgenic (Tg) mice and mice with transgene cassettes inserted at the E1 locus (Tg-E), B3 locus (Tg-B), and B3 and E1 loci (Tg-BE) at E16.5. Blue bars show the small RNAs from the sense Miwi2 promoter and antisense Dnmt3L (transgene sense strand), while the orange bars show the small RNAs from the antisense Miwi2 promoter and sense Dnmt3L (transgene antisense strand). (B) Size distribution of transgene-annotated small RNAs. The upper side represents the transgene sense strand where blue and purple indicate small RNAs with and without uracil as their first nucleotide, respectively. The lower side represents the transgene antisense strand where orange and purple indicate small RNAs with and without adenine at the tenth position, respectively. (C) Schematic diagram showing the directions of small RNAs. Red arrow indicates the expected transcript of asDnmt3L driven by the Miwi2 promoter. Light blue, blue, and gray arrows indicate transgene sense strands, while yellow, orange, and brown arrows indicate transgene antisense strands. (D) Ratio of transgene-annotated small RNAs in the fetal testis of Tg mice. The colors of the pie charts correspond to the colors of the arrows in C. The shaded orange color contains piRNAs from the transgene and the endogenous Dnmt3L. (E) Mapping of piRNAs of the Tg-B mice onto the transgene cassette sequence. The upper and lower sides represent the sense strand in blue and the antisense strand in orange, respectively.
