Molecular determinants for the layering and coarsening of biological condensates

• Published in: Aggregate (Hoboken) 2022-12, Vol.3 (6), p.n/a
• Main Authors: Latham, Andrew P., Zhang, Bin
• Format: Article
• Language: English
• Subjects: biological condensate; Cell cycle; Interfaces; intrinsically disordered protein; membraneless organelle; phase separation; Proteins; Ribonucleic acid; RNA; surface tension
• ISSN: 2692-4560; 2766-8541; 2692-4560
• DOI: 10.1002/agt2.306

Many membraneless organelles, or biological condensates, form through phase separation, and play key roles in signal sensing and transcriptional regulation. While the functional importance of these condensates has inspired many studies to characterize their stability and spatial organization, the underlying principles that dictate these emergent properties are still being uncovered. In this review, we examine recent work on biological condensates, especially multicomponent systems. We focus on connecting molecular factors such as binding energy, valency, and stoichiometry with the interfacial tension, explaining the nontrivial interior organization in many condensates. We further discuss mechanisms that arrest condensate coalescence by lowering the surface tension or introducing kinetic barriers to stabilize the multidroplet state. The diagram illustrates the four possible outcomes upon mixing two immiscible droplets, which are dictated by the interfacial tension between the two droplets and between the droplets and the solvent phase. Generalizations of this principle can be used to understand biocondensate organization and its connection with the interactions among the molecular components.