Unlabelled: Transposable elements (TEs) pose a threat to genome integrity, and the piRNA pathway in animal gonads plays a crucial role in silencing TE activity. While the transcriptional regulation of the piRNA pathway components in germ cells has been documented in mice and flies, the mechanisms orchestrating the transcriptional program of the somatic piRNA pathway in ovaries remains unresolved. Here, we demonstrate that Traffic jam (Tj), an orthologue of a large Maf transcription factor in mammals, is a master regulator of the piRNA pathway in ovarian somatic cells, playing a crucial role in maintaining TE silencing and genomic integrity in somatic tissues.
View Article and Find Full Text PDFPIWI-interacting RNAs (piRNAs) are a class of small non-coding RNAs that are essential for transposon control in animal gonads. In ovarian somatic cells, piRNAs are transcribed from large genomic regions called piRNA clusters, which are enriched for transposon fragments and act as a memory of past invasions. Despite being widely present across species, somatic piRNA clusters are difficult to identify and study due to their lack of sequence conservation and limited synteny.
View Article and Find Full Text PDFBackground: The piRNA pathway in animal gonads functions as an 'RNA-based immune system', serving to silence transposable elements and prevent inheritance of novel invaders. In Drosophila, this pathway relies on three gonad-specific Argonaute proteins (Argonaute-3, Aubergine and Piwi) that associate with 23-28 nucleotide piRNAs, directing the silencing of transposon-derived transcripts. Transposons constitute a primary driver of genome evolution, yet the evolution of piRNA pathway factors has not received in-depth exploration.
View Article and Find Full Text PDFThe PIWI-interacting RNA (piRNA) pathway prevents endogenous genomic parasites, i.e. transposable elements, from damaging the genetic material of animal gonadal cells.
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