Micropolarized to the core

Abstract

Macromolecules can undergo liquid–liquid phase separation to form condensates that have critical roles in biological functions and dysfunctions. A new study demonstrates that differences in micropolarity between components is a prime determinant of the multiphasic architecture of biomolecular condensates.

Fig. 1 |. Modulation of multiphasic biocondensate architecture.

a, Demixing of two different ELP macromolecules from a single-phase aqueous solution results in the formation of BMCs with core–shell miscibility characteristics that depend primarily on the difference in micropolarities between the component ELPs. b, The core–shell architecture of BMCs depends on factors that are intrinsic or extrinsic to the macromolecules. These factors determine the balance between thermodynamic preference for homotypic and heterotypic macromolecular interactions versus solvent–macromolecule interactions, and the resultant solvophobicity character of the component macromolecules. On a solvophobicity scale defined by the solvent, which can be as simple as water or dilute buffer or as complex as the cellular milieu, solvophilic macromolecules that interact favorably with the solvent will occupy the outer shell layers, whereas solvophobic macromolecules will prefer to occupy the core.