Rxivist logo

Membrane bending by protein phase separation

By Feng Yuan, Haleh Alimohamadi, Brandon Bakka, Andrea N. Trementozzi, Nicolas L. Fawzi, Padmini Rangamani, Jeanne C Stachowiak

Posted 22 May 2020
bioRxiv DOI: 10.1101/2020.05.21.109751

Membrane bending is a ubiquitous cellular process that is required for membrane traffic, cell motility, organelle biogenesis, and cell division. Proteins that bind to membranes using specific structural features, such as wedge-like amphipathic helices and crescent-shaped scaffolds, are thought to be the primary drivers of membrane bending. However, many membrane-binding proteins have substantial regions of intrinsic disorder, which lack a stable three-dimensional structure. Interestingly, many of these disordered domains have recently been found to form networks stabilized by weak, multi-valent contacts, leading to assembly of protein liquid phases on membrane surfaces. Here we ask how membrane-associated protein liquids impact membrane curvature. Using synthetic and cell-derived membrane vesicles, we find that liquid-liquid phase separation of membrane-associated disordered proteins creates a substantial compressive stress in the plane of the membrane. This stress drives the membrane to bend away from the protein layer, creating protein-lined membrane tubules. A simple mechanical model of this process accurately predicts the experimentally measured relationship between the rigidity of the membrane and the diameter of the membrane tubules. Discovery of this mechanism, which may be relevant to a broad range of membrane protrusions, illustrates that membrane remodeling is not exclusive to structured scaffolds, but can also be driven by the rapidly emerging class of liquid-like protein networks that assemble at membranes. ### Competing Interest Statement The authors have declared no competing interest.

Download data

  • Downloaded 973 times
  • Download rankings, all-time:
    • Site-wide: 11,902 out of 88,857
    • In biophysics: 376 out of 3,870
  • Year to date:
    • Site-wide: 1,444 out of 88,857
  • Since beginning of last month:
    • Site-wide: 641 out of 88,857

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide


Sign up for the Rxivist weekly newsletter! (Click here for more details.)