Proximity labeling identifies LOTUS domain proteins that promote the formation of perinuclear germ granules in C. elegans
Abstract
The germ line produces gametes that transmit genetic and epigenetic information to the next generation. Maintenance of germ cells and development of gametes require germ granules-well-conserved membraneless and RNA-rich organelles. The composition of germ granules is elusive owing to their dynamic nature and their exclusive expression in the germ line. Using C. elegans germ granule, called P granule, as a model system, we employed a proximity-based labeling method in combination with mass spectrometry to comprehensively define its protein components. This set of experiments identified over 200 proteins, many of which contain intrinsically disordered regions. An RNAi-based screen identified factors that are essential for P granule assembly, notably EGGD-1 and EGGD-2, two putative LOTUS-domain proteins. Loss of eggd-1 and eggd-2 results in separation of P granules from the nuclear envelope, germline atrophy and reduced fertility. We show that intrinsically disordered regions of EGGD-1 are required to anchor EGGD-1 to the nuclear periphery while its LOTUS domains are required to promote perinuclear localization of P granules. Together, our work expands the repertoire of P granule constituents and provides new insights into the role of LOTUS-domain proteins in germ granule organization.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file.Source data files are uploaded to Dryad: https://doi.org/10.5061/dryad.q2bvq83k9Scripts for data analysis are uploaded to Githubhttps://github.com/benpastore/TurboID
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Data from: Proximity labeling identifies LOTUS domain proteins that promote the formation of perinuclear germ granules in C. elegansDryad Digital Repository, doi:10.5061/dryad.q2bvq83k9.
Article and author information
Author details
Funding
National Institutes of Health (R00GM124460)
- Wen Tang
National Institutes of Health (R35GM142580)
- Wen Tang
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 17, 2021
- Preprint posted: July 27, 2021 (view preprint)
- Accepted: November 1, 2021
- Accepted Manuscript published: November 3, 2021 (version 1)
- Version of Record published: November 25, 2021 (version 2)
Copyright
© 2021, Price 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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