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Updated: Dec 15, 2025
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Assembly of Cell Mimicking Supported and Suspended Lipid Bilayer Models for the Study of Molecular Interactions
Published on: August 3, 2021
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Retromer forms low order oligomers on supported lipid bilayers
Catherine L Deatherage1, Joerg Nikolaus2, Erdem Karatekin3
1Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut, USA.
The Journal of Biological Chemistry
|July 12, 2020
Summary
Retromer protein complexes naturally form small oligomers on membranes. This intrinsic oligomerization, independent of cargo or accessory factors, suggests retromer facilitates bulk membrane trafficking.
Area of Science:
- Cell Biology
- Molecular Biology
- Membrane Trafficking
Background:
- Retromer is crucial for endosomal protein sorting and membrane recycling.
- Previous models suggested retromer oligomerization with accessory factors drives cargo clustering.
Purpose of the Study:
- To investigate the oligomeric state of retromer and its dependence on cargo and accessory factors.
- To test hypotheses about retromer-mediated cargo sorting.
Main Methods:
- Quantitative single-particle fluorescence microscopy.
- Reconstituted system with supported lipid bilayers, fluorescently labeled retromer, SNX3, RAB7, and WASHC2C.
Main Results:
- Retromer predominantly formed low-order oligomers (monomers to tetramers) on lipid bilayers.
- Oligomerization was largely unaffected by the presence of model cargo or accessory factors (SNX3, RAB7, WASHC2C).
Conclusions:
- Retromer exhibits intrinsic oligomerization propensity independent of cargo or accessory proteins.
- The SNX3-retromer complex functions as a minimally concentrative coat for bulk endosomal trafficking.
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