Back to Search
Start Over
Epigenetic inheritance mediated by coupling of RNAi and histone H3K9 methylation
- Source :
- Nature. June, 2018, Vol. 558 Issue 7710, p615, 5 p.
- Publication Year :
- 2018
-
Abstract
- Histone post-translational modifications (PTMs) are associated with epigenetic states that form the basis for cell-type-specific gene expression.sup.1,2. Once established, histone PTMs can be maintained by positive feedback involving enzymes that recognize a pre-existing histone modification and catalyse the same modification on newly deposited histones. Recent studies suggest that in wild-type cells, histone PTM-based positive feedback is too weak to mediate epigenetic inheritance in the absence of other inputs.sup.3-7. RNA interference (RNAi)-mediated histone H3 lysine 9 methylation (H3K9me) and heterochromatin formation define a potential epigenetic inheritance mechanism in which positive feedback involving short interfering RNA (siRNA) amplification can be directly coupled to histone PTM positive feedback.sup.8-14. However, it is not known whether the coupling of these two feedback loops can maintain epigenetic silencing independently of DNA sequence and in the absence of enabling mutations that disrupt genome-wide chromatin structure or transcription.sup.15-17. Here, using the fission yeast Schizosaccharomyces pombe, we show that siRNA-induced H3K9me and silencing of a euchromatic gene can be epigenetically inherited in cis during multiple mitotic and meiotic cell divisions in wild-type cells. This inheritance involves the spreading of secondary siRNAs and H3K9me3 to the targeted gene and surrounding areas, and requires both RNAi and H3K9me, suggesting that the siRNA and H3K9me positive-feedback loops act synergistically to maintain silencing. By contrast, when maintained solely by histone PTM positive feedback, silencing is erased by H3K9 demethylation promoted by Epe1, or by interallelic interactions that occur after mating to cells containing an expressed allele even in the absence of Epe1. These findings demonstrate that the RNAi machinery can mediate transgenerational epigenetic inheritance independently of DNA sequence or enabling mutations, and reveal a role for the coupling of the siRNA and H3K9me positive-feedback loops in the protection of epigenetic alleles from erasure. In Schizosaccharomyces pombe, histone H3K9 methylation acts synergistically with short interfering RNA to perpetuate gene silencing during multiple mitotic and meiotic cell divisions.<br />Author(s): Ruby Yu [sup.1] , Xiaoyi Wang [sup.1] , Danesh Moazed [sup.1] Author Affiliations: (1) Department of Cell Biology and Howard Hughes Medical Institute, Harvard Medical School, Boston, USA Main [...]
- Subjects :
- Epigenetic inheritance -- Research
Genetic research
Small interfering RNA -- Research
Histones -- Research
Base sequence
Genetic engineering
DNA binding proteins
Genomics
Chromatin
DNA
Genes
RNA interference
DNA sequencing
Transcription (Genetics)
Alleles
Methylation
RNA
Lysine
Enzymes
Environmental issues
Science and technology
Zoology and wildlife conservation
Subjects
Details
- Language :
- English
- ISSN :
- 00280836
- Volume :
- 558
- Issue :
- 7710
- Database :
- Gale General OneFile
- Journal :
- Nature
- Publication Type :
- Academic Journal
- Accession number :
- edsgcl.589835522
- Full Text :
- https://doi.org/10.1038/s41586-018-0239-3