Intrinsic hydrophobicity of IDP-based biomolecular condensates drives their partial drying on membrane surfaces
Abstract
The localization of biomolecular condensates to intracellular membrane surfaces has emerged as an important feature of sub-cellular organization. In this work, we study the wetting behavior of biomolecular condensates on various substrates. We use confocal microscopy to measure the contact angles of model condensates formed by intrinsically disordered protein Ddx4N. We show the importance of taking optical aberrations into account, as these impact apparent contact angle measurements. Ddx4N condensates are seen to partially dry (contact angles above 90°) a model membrane, with little dependence on the magnitude of charge on, or tyrosine content of, Ddx4N. Further contact angle measurements on surfaces of varying hydrophilicity reveal a preference of Ddx4N condensates for hydrophobic surfaces, suggesting an intrinsic repulsion between protein condensates and hydrophilic membrane surfaces. This observation is in line with previous studies relating protein adsorption to surface hydrophilicity. Our work advances the understanding of the molecular details governing the localization of biomolecular condensates.
Article Details
Journal Info
The Journal of Chemical Physics
American Institute of Physics
Authors (3)
J. Holland
Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford 1 , Oxford OX1 3QZ,
T. J. Nott
Department of Chemistry, King’s College London 2 , Britannia House, 7 Trinity Street, London SE1 1DB,
D. G. A. L. Aarts
Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford 1 , Oxford OX1 3QZ,