GSE107371 Hierarchical roles of mitochondrial PAPI and Zucchini in Bombyx germline piRNA biogenesis

Contributors : Kazumichi M Nishida ; Kazuhiro Sakakibara ; Mikiko C SiomiSeries Type : Other ; Non-coding RNA profiling by high throughput sequencingOrganism : Bombyx moriPIWI-interacting RNAs (piRNAs) are germline-enriched small RNAs that control transposons to maintain genome integrity1,2,3. To achieve this, piRNAs bind PIWI proteins upon being processed from piRNA precursors1,2,3. Bioinformatic studies of piRNA biogenesis in Drosophila showed that the piRNA 5 ′ end is formed by PIWI-Slicer or Zucchini (Zuc) endonucleolytic cleavage, while the 3′ end is formed by Zuc or Nibbler (Nbr) 3′-to-5′ exonucleolytic activity4,5,6. piRNA 3′-end formation in Bombyx was shown to be mediated by PNLDC1/Trimmer (Trim) 3′-to-5′ exonuclease7, while piRNA int ermediates are bound with PIWI anchored onto mitochondrial protein PAPI8. However, the requirement for Zuc and Nbr in piRNA biogenesis in Bombyx has not been elucidated. Here, we applied biochemical approaches to understand their involvement in piRNA biogenesis and revealed that Zuc endonuclease, bu t not Trim and Nbr exonucleases, plays a crucial role in Bombyx piRNA 3′-end formation. Loss of Zuc had little effect on the levels of Trim and Nbr, but led to the aberrant accumulation of piRNA intermediates within the PAPI complex, which were processed to mature piRNAs by recombinant Zuc. Zuc co purified with PAPI, and PAPI exerted RNA-binding activity only when Siwi coexisted with it and PAPI was phosphorylated, suggestin...

Source: GEO: Gene Expression Omnibus - March 1, 2018 Category: Genetics & Stem Cells Tags: Other Non-coding RNA profiling by high throughput sequencing Bombyx mori Source Type: research