RNA-Interference Components Are Dispensable for Transcriptional Silencing of the Drosophila Bithorax-Complex
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ArticleAuthors
Cernilogar, Filippo M.Burroughs, A. Maxwell
Lanzuolo, Chiara
Breiling, Achim
Imhof, Axel
Orlando, Valerio
KAUST Department
Biological and Environmental Sciences and Engineering (BESE) DivisionKAUST Environmental Epigenetics Research Program (KEEP)
Date
2013-06-13Metadata
Show full item recordAbstract
Background: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.Citation
Cernilogar 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.Publisher
Public Library of Science (PLoS)Journal
PLoS ONEISSN
19326203PubMed ID
23785447PubMed Central ID
PMC3681981Handle URI
http://hdl.handle.net/10754/325319Scopus Count
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