Amplification of siRNA in Caenorhabditis elegans generates a transgenerational sequence-targeted histone H3 lysine 9 methylation footprint

ABSTRACT: Exogenous double-stranded RNA (dsRNA) has been shown to exert homology-dependent effects at the level of both target mRNA stability and chromatin structure. Using C. elegans undergoing RNAi as an animal model, we have investigated the generality, scope, and longevity of chromatin-targeted dsRNA effects and their dependence on components of the RNAi machinery. Using high-resolution genome-wide chromatin profiling, we found that a diverse set of genes can be induced to acquire locus-specific enrichment of H3K9 trimethylation, with modification footprints extending several kilobases from the site of dsRNA homology and with locus specificity sufficient to distinguish the targeted locus from among all 20,000 genes in the C. elegans genome. Genetic analysis of the response indicated that factors responsible for secondary siRNA production during RNAi were required for effective targeting of chromatin. Temporal analysis revealed that H3K9 methylation, once triggered by dsRNA, can be maintained in the absence of dsRNA for at least two generations before being lost. These results implicate dsRNA-triggered chromatin modification in C. elegans as a programmable and locus-specific response defining a metastable state that can persist through generational boundaries. H3K9me3 nucleosome-IP sequencing and small RNA sequencing in C. elegans populations that underwent RNAi

ORGANISM(S): Caenorhabditis elegans

SUBMITTER: Sam Gu 

PROVIDER: E-GEOD-32631 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress