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Piwi-piRNA complex-mediated silencing of transposable elements through transcription termination

ABSTRACT: Piwi protein, guided by Piwi-interacting RNA (piRNA), establishes sequence-specific heterochromatin on transposable elements (TEs) in animal germ cells, thereby repressing TEs to preserve genomic integrity. We previously reported that TE silencing mediated by the Piwi-piRNA pathway can be divided into two distinct steps: the initiation and maintenance of silencing. During initiation, the Piwi-piRNA complex interferes with RNA polymerase II transcription through the effector complex containing Nxf2 and Panx, preceding chromatin compaction mediated by linker histone H1 and HP1a in the silencing-maintenance. However, the mechanisms underlying silencing initiation remain elusive. Here, we found that SUMOylated Panx recruits Sov, resulting in reporter gene silencing independent of H1 and HP1a. Additionally, Sov associates with PNUTS and Senataxin, both of which are involved in the transcription termination, and are required for Panx-mediated silencing. These findings reveal that transcription termination plays a critical role in the piRNA-guided transcriptional repression preceding heterochromatin formation on TEs.

ORGANISM(S): Drosophila melanogaster

PROVIDER: GSE293712 | GEO | 2025/10/28

REPOSITORIES: GEO

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