Compartmentalized oskar degradation in the germ plasm safeguards germline development
Abstract
Partitioning of mRNAs into ribonucleoprotein (RNP) granules supports diverse regulatory programs within the crowded cytoplasm. At least two types of RNP granules populate the germ plasm, a cytoplasmic domain at the posterior of the Drosophila oocyte and embryo. Germ granules deliver mRNAs required for germline development to pole cells, the germ cell progenitors. A second type of RNP granule, here named founder granules, contains oskar mRNA, which encodes the germ plasm organizer. Whereas oskar mRNA is essential for germ plasm assembly during oogenesis, we show that it is toxic to pole cells. Founder granules mediate compartmentalized degradation of oskar during embryogenesis to minimize its inheritance by pole cells. Degradation of oskar in founder granules is temporally and mechanistically distinct from degradation of oskar and other mRNAs during the maternal-to-zygotic transition. Our results show how compartmentalization in RNP granules differentially controls fates of mRNAs localized within the same cytoplasmic domain.
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Article and author information
Author details
Funding
National Institutes of Health (R01 GM067758)
- Elizabeth R Gavis
National Institutes of Health (R35 GM126967)
- Elizabeth R Gavis
National Institutes of Health (T32 GM007388)
- Elizabeth R Gavis
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Michael Buszczak, University of Texas Southwestern Medical Center, United States
Version history
- Received: July 6, 2019
- Accepted: January 7, 2020
- Accepted Manuscript published: January 7, 2020 (version 1)
- Version of Record published: January 28, 2020 (version 2)
Copyright
© 2020, Eichler 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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