Biogenesis of phased siRNAs on membrane-bound polysomes in Arabidopsis
- University of California, Riverside, United States
- Shenzhen University, China
- Institute of Genetics and Developmental Biology, China
Abstract
Small RNAs are central players in RNA silencing, yet their cytoplasmic compartmentalization and the effects it may have on their activities have not been studied at the genomic scale. Here we report that Arabidopsis microRNAs (miRNAs) and small interfering RNAs (siRNAs) are distinctly partitioned between the endoplasmic reticulum (ER) and cytosol. All miRNAs are associated with membrane-bound polysomes (MBPs) as opposed to polysomes in general. The MBP association is functionally linked to a deeply conserved and tightly regulated activity of miRNAs - production of phased siRNAs (phasiRNAs) from select target RNAs. The phasiRNA precursor RNAs, thought to be noncoding, are on MBPs and are occupied by ribosomes in a manner that supports miRNA-triggered phasiRNA production, suggesting that ribosomes on the rough ER impact siRNA biogenesis. This study reveals global patterns of cytoplasmic partitioning of small RNAs and expands the known functions of ribosomes and ER.
Data availability
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Endoplasmic reticulum as a hub organizing the activities of microRNAs and a subset of endogenous siRNAs in ArabidopsisPublicly available at the NCBI Gene Expression Omnibus (accession no. GSE82041).
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High-throughput sequencing of Arabidopsis microRNAs: evidence for frequent birth and death of MIRNA genesPublicly available at the NCBI Gene Expression Omnibus (accession no. GSE6682).
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Xuemei Chen
Gordon and Betty Moore Foundation (GBMF3046)
- Xuemei Chen
National Institutes of Health (GM061146)
- Xuemei Chen
Guangdong Innovation Research Team Funds (2014ZT05S078)
- Xuemei Chen
National Science Foundation of China (91440105)
- Xuemei Chen
Shenzhen municipality (JCYJ20151116155209176)
- Shengben Li
Shenzhen municipality (KQCX2015033110464302)
- Shengben Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Li 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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Biogenesis of phased siRNAs on membrane-bound polysomes in Arabidopsis
eLife 5:e22750.
https://doi.org/10.7554/eLife.22750
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