Size Conservation Emerges Spontaneously in Biomolecular Condensates Formed by Scaffolds and Surfactant Clients

摘要: Biomolecular condensates are liquid-like membraneless compartments that contribute to the spatiotemporal organization of proteins, RNA, and other biomolecules inside cells. Some compartments, such as nucleoli, dispersed different do not grow beyond a certain size, or present coalescence over time. In this work, using minimal protein model, we show phase separation binary mixtures scaffolds low-valency clients can act surfactants - i.e., significantly reduce droplet surface tension yield either single drop multiple droplets conserve their sizes on long timescales (herein 9multidroplet size-conserved9), depending scaffold client ratio. Our simulations demonstrate connectivity condensate regulate balance between these two scenarios. Multidroplet size-conserved behavior spontaneously arises at increasing surfactant-to-scaffold concentrations, when interfacial penalty for creating small liquid is sufficiently reduced by surfactant proteins preferentially located interface. contrast, low concentrations enable continuous growth fusion without restrictions. Overall, our work proposes one potential thermodynamic mechanism help rationalize how coexisting persist cells shedding light roles general biomolecular features connectivity, binding affinity, composition in process.