Normalized coverage per million (CPM) of mapped piRNA reads (> 25-nt) on the CDS region of 4 representative genes. Colored areas represent reads from Siwi-D670A-overexpressed library and the grey areas represent reads from wild-type Siwi-overexpressed library. (Top) piRNA reads mapped to both sense and antisense directions on a TE gene (putative reverse transcriptase) and a potential TE gene (uncharacterized protein) with similar RPM between the two libraries. (Bottom) piRNA reads mapped to the sense direction on non-TE genes (ribosomal protein S9 and eIF4E-1) with elevated RPM in the Siwi-D670A library. Elevated peaks appear to spread around the pre-existing peaks on these genes in the wild-type library. 