RNA-seq and small RNA-seq data in boot mutant ovaries

PIWI-interacting RNAs (piRNAs) silence transposons to maintain germline genome integrity in animal gonad. Most of piRNAs arise from piRNA clusters. In Drosophila, a Heterochromatin protein family member Rhino defines the germline piRNA clusters, so-called dual-strand clusters, and elicits the transcription. However, how the clusters are transcribed is largely unknown. Here, we characterized CG13741/Bootlegger (Boot) as an essential nuclear piRNA factor for piRNA production from the dual-strand clusters. Herein Boot is referred as Egret (Egt). Boot is indispensable for suppressing the splicing of the precursors through regulating Cuff function and furthermore for the recruitment of an RNA export factor Hel25E/UAP56 to the transcription sites in the nucleus. Our findings indicate that Boot acts in the transcription and the export of the precursors from dual-strand piRNA clusters. Genome-wide changes in RNA and small RNA expression levels in the boot mutant ovaries.