The proteome at piRNA-target transcripts

ABSTRACT: Co-transcriptional gene silencing mediated by small RNA pathways is primarily studied in the context of heterochromatin formation. These pathways are known to target nascent RNAs, yet their intersection with cellular processes determining the fate of the nascent transcripts remain unclear. In this study, we investigated the proteome associated with piRNA-target transcripts using biotinylation-based proximity labeling and co-immunoprecipitation assays, followed by quantitative mass spectrometry. Our findings reveal two paralogous proteins, CG31510 and CG7065, as critical piRNA pathway factors that physically connect the nulear RNA exosome, the central cellular 3’ to 5’ exo-ribonuclease complex, to the Piwi-silencing complex through a novel poly-proline binding domain. Notably, we show that the nuclear RNA exosome is required for transposon repression through the Piwi-piRNA pathway in Drosophila. Furthermore, we demonstrate that the three adaptor complexes of the nuclear exosome –PAXT, NEXT, and TRAMP– are redundantly required for degrading piRNA target transcripts. Our findings uncover an evolutionarily conserved principle whereby the nuclear RNA exosome is integral to diverse co-transcriptional silencing processes controlled by small RNAs.

INSTRUMENT(S):

ORGANISM(S): Drosophila Melanogaster (fruit Fly)

TISSUE(S): Somatic Cell

SUBMITTER: Richard Imre  

LAB HEAD: Julius Fabian Brennecke

PROVIDER: PXD054812 | Pride | 2026-02-26

REPOSITORIES: Pride