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bioRxiv · 10.1101/489658

A quantitative inventory of yeast P body proteins reveals principles of compositional specificity

Xing, W.·Muhlrad, D.·Parker, R.·Rosen, M. K.
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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 cooperatively. Our data indicate that P bodies, and probably other condensates, are biochemically simpler than suggested by proteomic analyses, with implications for specificity, reconstitution and evolution.

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Xing, W., Muhlrad, D., Parker, R., Rosen, M. K.. 2018-12-07. A quantitative inventory of yeast P body proteins reveals principles of compositional specificity. https://doi.org/10.1101/489658

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