Novel LOTUS-domain proteins are organizational hubs that recruit C. elegans Vasa to germ granules
- New York University, United States
- McGill University, Canada
- Max Delbrück Center for Molecular Medicine, Germany
- New York University Abu Dhabi, United Arab Emirates
Abstract
We describe MIP-1 and MIP-2, novel paralogous C. elegans germ granule components that interact with the intrinsically disordered MEG-3 protein. These proteins promote P granule condensation, form granules independently of MEG-3 in the postembryonic germ line, and balance each other in regulating P granule growth and localization. MIP-1 and MIP-2 each contain two LOTUS domains and intrinsically disordered regions and form homo- and heterodimers. They bind and anchor the Vasa homolog GLH-1 within P granules and are jointly required for coalescence of MEG-3, GLH-1, and PGL proteins. Animals lacking MIP-1 and MIP-2 show temperature-sensitive embryonic lethality, sterility, and mortal germ lines. Germline phenotypes include defects in stem cell self-renewal, meiotic progression, and gamete differentiation. We propose that these proteins serve as scaffolds and organizing centers for ribonucleoprotein networks within P granules that help recruit and balance essential RNA processing machinery to regulate key developmental transitions in the germ line.
Data availability
All mass spectrometry raw data have been deposited to the PRIDE repository with the dataset identifier PXD012852. All other data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 2A-C; Figure 2-figure supplement 2; Figure 6A,B; Figure 8E; Figure 9B; Figure 9-figure supplement 1; Figure 10C.
Article and author information
Author details
Kristin C Gunsalus
Funding
New York University Abu Dhabi (ADPHG CGSB)
- Patricia Giselle Cipriani
- Hala Fahs
- Fabio Piano
- Kristin C Gunsalus
New York University Abu Dhabi
- Patricia Giselle Cipriani
- Olivia Bay
- John Zinno
- Michelle Gutwein
- Hin Hark Gan
- George Chung
- Fabio Piano
- Kristin C Gunsalus
Canadian Institutes of Health Research (MOP 123352)
- Vinay K Mayya
- Thomas F Duchaine
Charlotte and Leo Karassik Foundation
- Vinay K Mayya
Bundesministerium für Bildung und Forschung (0315362)
- Jia-Xuan Chen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Cipriani 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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