Composition can buffer protein dynamics within liquid-like condensates.

Jelenic, S.; Bindics, J.; Czermak, P.; Pillai, B. R.; Ruer, M.; Holehouse, A. S.; Saha, S.

doi:10.1101/2022.05.16.492059

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bioRxiv · 10.1101/2022.05.16.492059

Composition can buffer protein dynamics within liquid-like condensates.

Jelenic, S.·Bindics, J.·Czermak, P.·Pillai, B. R.·Ruer, M.·Holehouse, A. S.·Saha, S.

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Abstract

Most non-membrane-bound compartments in cells that form via phase separation have complex composition. While phase separation of individual proteins that form these compartments is well-documented, the mechanisms that modulate dynamics of individual proteins in multicomponent systems remain unclear. Here, we used in vitro reconstitution and in vivo experiments to investigate how the dynamics of a scaffold protein PGL-3 is regulated within the liquid-like P granule compartment in C. elegans. Using mutational and biophysical perturbations, we generated PGL-3 constructs that form condensates in vitro with widely varying dynamics. Using these PGL-3 constructs, we show that introducing other P granule components buffers against change of dynamics within liquid-like condensates. This dynamics-buffering effect is mediated by weak interactions among two or more components. Such dynamics-buffering may contribute to robust functional output of cellular liquid-like compartments.

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Jelenic, S., Bindics, J., Czermak, P., Pillai, B. R., Ruer, M., Holehouse, A. S., Saha, S.. 2022-05-16. Composition can buffer protein dynamics within liquid-like condensates.. https://doi.org/10.1101/2022.05.16.492059

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