Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.

RNA interference (RNAi) is a conserved mechanism of small RNA-mediated genome regulation commonly involved in suppression of transposable elements (TEs) through both post-transcriptional silencing, and transcriptional repression via heterochromatin assembly. The fission yeast Schizosaccharomyces pom...

Full description

Saved in:
Bibliographic Details
Main Authors: Elliott Chapman, Francesca Taglini, Elizabeth H Bayne
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2022-02-01
Series:PLoS Genetics
Online Access:https://journals.plos.org/plosgenetics/article/file?id=10.1371/journal.pgen.1010100&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849337138854756352
author Elliott Chapman
Francesca Taglini
Elizabeth H Bayne
author_facet Elliott Chapman
Francesca Taglini
Elizabeth H Bayne
author_sort Elliott Chapman
collection DOAJ
description RNA interference (RNAi) is a conserved mechanism of small RNA-mediated genome regulation commonly involved in suppression of transposable elements (TEs) through both post-transcriptional silencing, and transcriptional repression via heterochromatin assembly. The fission yeast Schizosaccharomyces pombe has been extensively utilised as a model for studying RNAi pathways. However, this species is somewhat atypical in that TEs are not major targets of RNAi, and instead small RNAs correspond primarily to non-coding pericentromeric repeat sequences, reflecting a specialised role for the pathway in promoting heterochromatin assembly in these regions. In contrast, in the related fission yeast Schizosaccharomyces japonicus, sequenced small RNAs correspond primarily to TEs. This suggests there may be fundamental differences in the operation of RNAi pathways in these two related species. To investigate these differences, we probed RNAi function in S. japonicus. Unexpectedly, and in contrast to S. pombe, we found that RNAi is essential in this species. Moreover, viability of RNAi mutants can be rescued by mutations implicated in enhancing RNAi-independent heterochromatin propagation. These rescued strains retain heterochromatic marks on TE sequences, but exhibit derepression of TEs at the post-transcriptional level. Our findings indicate that S. japonicus retains the ancestral role of RNAi in facilitating suppression of TEs via both post-transcriptional silencing and heterochromatin assembly, with specifically the heterochromatin pathway being essential for viability, likely due to a function in genome maintenance. The specialised role of RNAi in heterochromatin assembly in S. pombe appears to be a derived state that emerged after the divergence of S. japonicus.
format Article
id doaj-art-b591aa463d29457ebf381a55a605ed6e
institution Kabale University
issn 1553-7390
1553-7404
language English
publishDate 2022-02-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Genetics
spelling doaj-art-b591aa463d29457ebf381a55a605ed6e2025-08-20T03:44:46ZengPublic Library of Science (PLoS)PLoS Genetics1553-73901553-74042022-02-01182e101010010.1371/journal.pgen.1010100Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.Elliott ChapmanFrancesca TagliniElizabeth H BayneRNA interference (RNAi) is a conserved mechanism of small RNA-mediated genome regulation commonly involved in suppression of transposable elements (TEs) through both post-transcriptional silencing, and transcriptional repression via heterochromatin assembly. The fission yeast Schizosaccharomyces pombe has been extensively utilised as a model for studying RNAi pathways. However, this species is somewhat atypical in that TEs are not major targets of RNAi, and instead small RNAs correspond primarily to non-coding pericentromeric repeat sequences, reflecting a specialised role for the pathway in promoting heterochromatin assembly in these regions. In contrast, in the related fission yeast Schizosaccharomyces japonicus, sequenced small RNAs correspond primarily to TEs. This suggests there may be fundamental differences in the operation of RNAi pathways in these two related species. To investigate these differences, we probed RNAi function in S. japonicus. Unexpectedly, and in contrast to S. pombe, we found that RNAi is essential in this species. Moreover, viability of RNAi mutants can be rescued by mutations implicated in enhancing RNAi-independent heterochromatin propagation. These rescued strains retain heterochromatic marks on TE sequences, but exhibit derepression of TEs at the post-transcriptional level. Our findings indicate that S. japonicus retains the ancestral role of RNAi in facilitating suppression of TEs via both post-transcriptional silencing and heterochromatin assembly, with specifically the heterochromatin pathway being essential for viability, likely due to a function in genome maintenance. The specialised role of RNAi in heterochromatin assembly in S. pombe appears to be a derived state that emerged after the divergence of S. japonicus.https://journals.plos.org/plosgenetics/article/file?id=10.1371/journal.pgen.1010100&type=printable
spellingShingle Elliott Chapman
Francesca Taglini
Elizabeth H Bayne
Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.
PLoS Genetics
title Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.
title_full Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.
title_fullStr Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.
title_full_unstemmed Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.
title_short Separable roles for RNAi in regulation of transposable elements and viability in the fission yeast Schizosaccharomyces japonicus.
title_sort separable roles for rnai in regulation of transposable elements and viability in the fission yeast schizosaccharomyces japonicus
url https://journals.plos.org/plosgenetics/article/file?id=10.1371/journal.pgen.1010100&type=printable
work_keys_str_mv AT elliottchapman separablerolesforrnaiinregulationoftransposableelementsandviabilityinthefissionyeastschizosaccharomycesjaponicus
AT francescataglini separablerolesforrnaiinregulationoftransposableelementsandviabilityinthefissionyeastschizosaccharomycesjaponicus
AT elizabethhbayne separablerolesforrnaiinregulationoftransposableelementsandviabilityinthefissionyeastschizosaccharomycesjaponicus