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Updated: Jun 17, 2025
10:28
Expression, Purification, and Liposome Binding of Budding Yeast SNX-BAR Heterodimers
Published on: December 6, 2019
7.8K
Structural basis for coupling of the WASH subunit FAM21 with the endosomal SNX27-Retromer complex
Qian Guo1, Kai-En Chen1, Manuel Gimenez-Andres2
1The University of Queensland, Institute for Molecular Bioscience, St Lucia, QLD 4072, Australia.
Summary
The Retromer-SNX27 complex links to the WASH complex via FAM21, regulating actin nucleation for endosomal recycling. This interaction is crucial for forming functional endosomal membrane domains.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Endosomal membrane trafficking relies on protein coats and actin-rich domains.
- The Retromer complex and sorting nexins (SNXs), like SNX27, are key players.
- SNX27-Retromer interacts with the Wiskott-Aldrich syndrome protein and SCAR homolog (WASH) complex to organize actin.
Purpose of the Study:
- To elucidate the molecular mechanisms of interaction between SNX27-Retromer and the WASH complex.
- To understand how FAM21 mediates these interactions.
- To determine the functional significance of these interactions for endosomal recycling.
Main Methods:
- X-ray crystallography
- Computational modeling
- Biochemical assays
- Cellular validation studies
Main Results:
- FAM21 binds SNX27 via acidic-Asp-Leu-Phe (aDLF) motifs and Retromer through overlapping repeats and a Pro-Leu motif.
- These interactions involve VPS35 and VPS29 subunits of Retromer.
- Mutating the primary VPS35-binding site partially disrupts WASH association but not cargo recycling, suggesting functional redundancy.
Conclusions:
- Detailed molecular basis for SNX27-Retromer coupling to the WASH complex established.
- Overlapping and multiplexed interactions are critical for WASH complex recruitment and endosomal activity.
- These findings are essential for understanding the dynamic assembly of endosomal membrane recycling domains.
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