Decoding the physical principles of two-component biomolecular phase separation

eLife

Ned S Wingreen¹  Yaojun Zhang²  Benjamin G Weiner³  Yigal Meir³  Bin Xu³ 

[1] Department of Physics, Ben Gurion University of the Negev, Beersheba, Israel;Center for the Physics of Biological Function, Princeton University, Princeton, United States;Department of Physics, Princeton University, Princeton, United States;

关键词: phase separation;    biomolecular condensates;    associative polymers;    molecular dynamics simulations;   

DOI  :  10.7554/eLife.62403

来源: DOAJ

【 摘 要 】

Cells possess a multiplicity of non-membrane-bound compartments, which form via liquid-liquid phase separation. These condensates assemble and dissolve as needed to enable central cellular functions. One important class of condensates is those composed of two associating polymer species that form one-to-one specific bonds. What are the physical principles that underlie phase separation in such systems? To address this question, we employed coarse-grained molecular dynamics simulations to examine how the phase boundaries depend on polymer valence, stoichiometry, and binding strength. We discovered a striking phenomenon – for sufficiently strong binding, phase separation is suppressed at rational polymer stoichiometries, which we termed the magic-ratio effect. We further developed an analytical dimer-gel theory that confirmed the magic-ratio effect and disentangled the individual roles of polymer properties in shaping the phase diagram. Our work provides new insights into the factors controlling the phase diagrams of biomolecular condensates, with implications for natural and synthetic systems.

【 授权许可】

Unknown