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arXiv · 2101.01164

Stoichiometry controls the dynamics of liquid condensates of associative proteins

Pierre Ronceray·Yaojun Zhang·Xichong Liu·Ned S. Wingreen
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Abstract

Multivalent associative proteins with strong complementary interactions play a crucial role in phase separation of intracellular liquid condensates. We study the internal dynamics of such "bond-network" condensates comprised of two complementary proteins via scaling analysis and molecular dynamics. We find that when stoichiometry is balanced, relaxation slows down dramatically due to a scarcity of alternative partners following a bond break. This microscopic slow-down strongly affects the bulk diffusivity, viscosity and mixing, which provides a means to experimentally test our predictions.

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Pierre Ronceray, Yaojun Zhang, Xichong Liu, Ned S. Wingreen. 2021-01-04. Stoichiometry controls the dynamics of liquid condensates of associative proteins. https://doi.org/10.1103/physrevlett.128.038102

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