Recruitment of mRNAs to P granules by condensation with intrinsically-disordered proteins
RNA granules are protein/RNA condensates. How specific mRNAs are recruited to cytoplasmic RNA granules is not known. Here we characterize the transcriptome and assembly of P granules, RNA granules in the C. elegans germ plasm. We find that P granules recruit mRNAs by condensation with the disordered protein MEG-3. MEG-3 traps mRNAs into non-dynamic condensates in vitro and binds to ~500 mRNAs in vivo in a sequence-independent manner that favors embryonic mRNAs with low ribosome coverage. Translational stress causes additional mRNAs to localize to P granules and translational activation correlates with P granule exit for two mRNAs coding for germ cell fate regulators. Localization to P granules is not required for translational repression but is required to enrich mRNAs in the germ lineage for robust germline development. Our observations reveal similarities between P granules and stress granules and identify intrinsically-disordered proteins as drivers of RNA condensation during P granule assembly.
Sequencing data have been deposited in GEO under accession number GSE139881,GSE139878, GSE139879 and GSE139880.Description of iCLIP analysis and additional python codes are deposited in Github :https://github.com/fishhead1978/iCLIP_2019
Recruitment of mRNAs to P granules by gelation with intrinsically-disordered proteins (iCLIP resultsNCBI Gene Expression Omnibus, GSE139878.
Recruitment of mRNAs to P granules by gelation with intrinsically-disordered proteins (RNAseq datasets)NCBI Gene Expression Omnibus, GSE139879.
Article and author information
National Institutes of Health (R37 HD37047)
- Geraldine Seydoux
Howard Hughes Medical Institute
- Geraldine Seydoux
National Institutes of Health (T32 GM007445)
- John Paul T Ouyang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Timothy W Nilsen, Case Western Reserve University, United States
- Received: October 19, 2019
- Accepted: January 23, 2020
- Accepted Manuscript published: January 24, 2020 (version 1)
- Version of Record published: February 7, 2020 (version 2)
© 2020, Lee 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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