Circadian RNA expression elicited by 3'-UTR IRAlu-paraspeckle associated elements
Abstract
Paraspeckles are nuclear bodies form around the long non-coding RNA, Neat1, and RNA-binding proteins. While their role is not fully understood, they are believed to control gene expression at a post-transcriptional level by means of the nuclear retention of mRNA containing in their 3'-UTR inverted repeats of Alu sequences (IRAlu). In this study, we found that, in pituitary cells, all components of paraspeckles including four major proteins and Neat1 displayed a circadian expression pattern. Furthermore the insertion of IRAlu at the 3'-UTR of the EGFP cDNA led to a rhythmic circadian nuclear retention of the egfp mRNA that was lost when paraspeckles were disrupted whereas insertion of a single antisense Alu had only a weak effect. Using real-time video-microscopy, these IRAlu were further shown to drive a circadian expression of EGFP protein. This study shows that paraspeckles, thanks to their circadian expression, control circadian gene expression at a post-transcriptional level.
Data availability
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Determination of the RNA linked to the paraspeckles in the GH4C1 cell linePublicly available at the NCBI Gene Expression Omnibus (accession no: GSE81972).
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Nascent-Seq Reveals Novel Features of Mouse Circadian Transcriptional RegulationPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE36916).
Article and author information
Author details
Funding
Pfizer-SFE award (Research price 2014)
- Anne-Marie François-Bellan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Torres et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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