Condensation of Ede1 promotes the initiation of endocytosis

  1. Mateusz Kozak
  2. Marko Kaksonen  Is a corresponding author
  1. University of Geneva, Switzerland

Abstract

Clathrin-mediated endocytosis is initiated by a network of weakly interacting proteins through a poorly understood mechanism. Ede1, the yeast homologue of mammalian Eps15, is an early-arriving endocytic protein and a key initiation factor. In the absence of Ede1, most other early endocytic proteins lose their punctate localization and endocytic uptake is decreased. We show that in yeast cells, cytosolic concentration of Ede1 is buffered at a critical level. Excess amounts of Ede1 form large condensates which recruit other endocytic proteins and exhibit properties of phase-separated liquid droplets. We demonstrate that the central region of Ede1, containing a coiled-coil and a prion-like region, is essential for both the condensate formation and the function of Ede1 in endocytosis. The functionality of Ede1 mutants lacking the central region can be partially rescued by an insertion of heterologous prion-like domains. Conversely, fusion of a heterologous lipid-binding domain with the central region of Ede1 can promote clustering into stable plasma membrane domains. We propose that the ability of Ede1 to form condensed networks supports the clustering of early endocytic proteins and promotes the initiation of endocytosis.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting source data files.

Article and author information

Author details

  1. Mateusz Kozak

    Department of Biochemistry, University of Geneva, Geneva, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1354-693X
  2. Marko Kaksonen

    Department of Biochemistry, University of Geneva, Geneva, Switzerland
    For correspondence
    marko.kaksonen@unige.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3645-7689

Funding

SNSF (31003A_163267)

  • Marko Kaksonen

SNSF (310030B_182825)

  • Marko Kaksonen

NCCR Chemical Biology

  • Marko Kaksonen

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2022, Kozak & Kaksonen

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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https://doi.org/10.7554/eLife.72865

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