GSE117658 Caenorhabditis elegans heterochromatin factor SET-32 plays an essential role in transgenerational initiation of nuclear RNAi-mediated epigenetic silencing (ChIP-Seq)

Contributors : Natallia Kalinava ; Sam G GuSeries Type : Genome binding/occupancy profiling by high throughput sequencingOrganism : Caenorhabditis elegansEpigenetic inheritance contributes fundamentally to transgenerational physiology and fitness. Mechanistic understanding of RNA-mediated chromatin modification and transgenerational epigenetic inheritance, which in C. elegans can be triggered by exogenous double-stranded RNA (exo-dsRNA) or facilitated by endogenous small interfering RNAs (endo-siRNAs), has mainly been limited to the post-initiation phases of silencing. Indeed, the dynamic process by which nuclear RNAi engages a transcriptionally active target, before the repressive state is stably established, remains largely a mystery. Here we found that the onset of exo-dsRNA-induced nuclear RNAi is a transgenerational process, and that establishment requires SET-32, one of the three putative histone methyltransferases (HMTs) that are required for H3K9me3 deposition at the nuclear RNAi targets. We also performed multigenerational whole-genome analyses to examine the establishment of silencing at endogenous targets of germline nuclear RNAi. The nuclear Argonaute (AGO) protein HRDE-1 is essential for the maintenance of nuclear RNAi. Repairing a loss-of-function mutation in hrde-1 by CRISPR restored the silencing of endogenous targets in animals carrying wild type set-32. However, for numerous endogenous targets, repairing the hrde-1 mutation in a set-32;hrde-1 double mutant ...
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Genome binding/occupancy profiling by high throughput sequencing Caenorhabditis elegans Source Type: research