3Department of Biology [Fort Collins] (Colorado State University
Biology Building, Room 111
1878 Campus Delivery
Fort Collins, CO 80523-1878 - United States)
4Imagerie et Modélisation - Imaging and Modeling (Département Biologie computationnelle,
Département de Biologie cellulaire et Infection,
25-28, rue du docteur Roux, 75724 Paris Cedex 15 - France)
Abstract : Caenorhabditis elegans early embryos generate cell-specific transcriptomes despite lacking active transcription. This presents an opportunity to study mechanisms of post-transcriptional regulatory control. In seeking the mechanisms behind this patterning, we discovered that some cell-specific mRNAs accumulate non-homogenously within cells, localizing to membranes, P granules (associated with progenitor germ cells in the P lineage), and P-bodies (associated with RNA processing). Transcripts differed in their dependence on 3'UTRs and RNA Binding Proteins, suggesting diverse regulatory mechanisms. Notably, we found strong but imperfect correlations between low translational status and P granule localization within the progenitor germ lineage. By uncoupling these, we untangled a long-standing question: Are mRNAs directed to P granules for translational repression or do they accumulate there as a downstream step? We found translational repression preceded P granule localization and could occur independent of it. Further, disruption of translation was sufficient to send homogenously distributed mRNAs to P granules. Overall, we show transcripts important for germline development are directed to P granules by translational repression, and this, in turn, directs their accumulation in the progenitor germ lineage where their repression can ultimately be relieved. Summary Maternally loaded mRNAs localize non-homogeneously within C. elegans early embryos correlating with their translational status and lineage-specific fates.
https://hal-pasteur.archives-ouvertes.fr/pasteur-02559475
Contributor : Marie Lemesle <>
Submitted on : Thursday, April 30, 2020 - 2:02:08 PM Last modification on : Friday, September 4, 2020 - 12:08:01 PM
Dylan Parker, Lindsay Winkenbach, Samuel Boyson, Matthew Saxton, Camryn Daidone, et al.. mRNA localization is linked to translation regulation in the Caenorhabditis elegans germ lineage. 2020. ⟨pasteur-02559475⟩