A quantitative inventory of yeast P body proteins reveals principles of composition and specificity
Abstract
P bodies are archetypal biomolecular condensates that concentrate proteins and RNA without a surrounding membrane. While dozens of P body proteins are known, the concentrations of components in the compartment have not been measured. We used live cell imaging to generate a quantitative inventory of the major proteins in yeast P bodies. Only 7 proteins are highly concentrated in P bodies (5.1-15 uM); the 24 others examined are appreciably lower (most ≤ 2.6 uM). P body concentration correlates inversely with cytoplasmic exchange rate. Sequence elements driving Dcp2 concentration into P bodies are distributed across the protein and act synergistically. Our data indicate that P bodies, and probably other condensates, are compositionally simpler than suggested by proteomic analyses, with implications for specificity, reconstitution and evolution.
Data availability
All data have been submitted to Dryad, doi:10.5061/dryad.02v6wwq0q.
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Data from: A quantitative inventory of yeast P body proteins reveals principles of composition and specificityDryad Digital Repository, 10.5061/dryad.02v6wwq0q.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Wenmin Xing
- Denise Muhlrad
- Roy Parker
- Michael K Rosen
Welch Foundation
- Michael K Rosen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Xing 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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