RNA-Interference Components Are Dispensable for Transcriptional Silencing of the Drosophila Bithorax-Complex
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AuthorsCernilogar, Filippo M.
Burroughs, A. Maxwell
KAUST DepartmentBiological and Environmental Sciences and Engineering (BESE) Division
KAUST Environmental Epigenetics Research Program (KEEP)
Permanent link to this recordhttp://hdl.handle.net/10754/325319
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AbstractBackground:Beyond their role in post-transcriptional gene silencing, Dicer and Argonaute, two components of the RNA interference (RNAi) machinery, were shown to be involved in epigenetic regulation of centromeric heterochromatin and transcriptional gene silencing. In particular, RNAi mechanisms appear to play a role in repeat induced silencing and some aspects of Polycomb-mediated gene silencing. However, the functional interplay of RNAi mechanisms and Polycomb group (PcG) pathways at endogenous loci remains to be elucidated.Principal Findings:Here we show that the endogenous Dicer-2/Argonaute-2 RNAi pathway is dispensable for the PcG mediated silencing of the homeotic Bithorax Complex (BX-C). Although Dicer-2 depletion triggers mild transcriptional activation at Polycomb Response Elements (PREs), this does not induce transcriptional changes at PcG-repressed genes. Moreover, Dicer-2 is not needed to maintain global levels of methylation of lysine 27 of histone H3 and does not affect PRE-mediated higher order chromatin structures within the BX-C. Finally bioinformatic analysis, comparing published data sets of PcG targets with Argonaute-2-bound small RNAs reveals no enrichment of these small RNAs at promoter regions associated with PcG proteins.Conclusions:We conclude that the Dicer-2/Argonaute-2 RNAi pathway, despite its role in pairing sensitive gene silencing of transgenes, does not have a role in PcG dependent silencing of major homeotic gene cluster loci in Drosophila. © 2013 Cernilogar et al.
CitationCernilogar FM, Burroughs AM, Lanzuolo C, Breiling A, Imhof A, et al. (2013) RNA-Interference Components Are Dispensable for Transcriptional Silencing of the Drosophila Bithorax-Complex. PLoS ONE 8: e65740. doi:10.1371/journal.pone.0065740.
PublisherPublic Library of Science (PLoS)
PubMed Central IDPMC3681981
- Chromatin-associated RNA interference components contribute to transcriptional regulation in Drosophila.
- Authors: Cernilogar FM, Onorati MC, Kothe GO, Burroughs AM, Parsi KM, Breiling A, Lo Sardo F, Saxena A, Miyoshi K, Siomi H, Siomi MC, Carninci P, Gilmour DS, Corona DF, Orlando V
- Issue date: 2011 Nov 6
- Drosophila Argonaute-1 is critical for transcriptional cosuppression and heterochromatin formation.
- Authors: Pushpavalli SN, Bag I, Pal-Bhadra M, Bhadra U
- Issue date: 2012 Apr
- RNAi components are required for nuclear clustering of Polycomb group response elements.
- Authors: Grimaud C, Bantignies F, Pal-Bhadra M, Ghana P, Bhadra U, Cavalli G
- Issue date: 2006 Mar 10
- Polycomb response elements mediate the formation of chromosome higher-order structures in the bithorax complex.
- Authors: Lanzuolo C, Roure V, Dekker J, Bantignies F, Orlando V
- Issue date: 2007 Oct
- Role of histone H3 lysine 27 methylation in Polycomb-group silencing.
- Authors: Cao R, Wang L, Wang H, Xia L, Erdjument-Bromage H, Tempst P, Jones RS, Zhang Y
- Issue date: 2002 Nov 1
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