Liquid–liquid phase separation and related phase transitions have emerged as generic mechanisms in living cells for the formation of membraneless compartments or biomolecular condensates. The surface between two immiscible phases has an interfacial tension, generating capillary forces that can perform work on the surrounding environment. Here we present the physical principles of capillarity, including examples of how capillary forces structure multiphase condensates and remodel biological substrates. As with other mechanisms of intracellular force generation, for example, molecular motors, capillary forces can influence biological processes. Identifying the biomolecular determinants of condensate capillarity represents an exciting frontier, bridging soft matter physics and cell biology.
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We thank members of our laboratories for helpful discussions; and M. Haataja for helpful comments on the manuscript. We acknowledge support from the Howard Hughes Medical Institute, the Princeton Biomolecular Condensate Program, and grants from the Princeton Center for Complex Materials, a MRSEC (NSF DMR-2011750), and the AFOSR MURI ‘Uncovering and applying the interfacial design principles of multiphasic natural and synthetic organelles’ (FA9550-20-1-0241). B.G. acknowledges the PD Soros Foundation. Both B.G. and Y.K. are supported by the NSF GRFP (DGE-2039656).
C.P.B. is a founder of and consultant for Nereid Therapeutics. All other authors declare no competing interests.
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Gouveia, B., Kim, Y., Shaevitz, J.W. et al. Capillary forces generated by biomolecular condensates. Nature 609, 255–264 (2022). https://doi.org/10.1038/s41586-022-05138-6