Related Experiment Video
Updated: Jun 20, 2026
10:28
Expression, Purification, and Liposome Binding of Budding Yeast SNX-BAR Heterodimers
Published on: December 6, 2019
The sorting nexin Snx21 promotes flotillin-mediated endocytosis
Tamás Maruzs1, Enikő Lakatos1,2, Dalma Feil-Börcsök1
1Institute of Genetics, HUN-REN Biological Research Centre, Szeged, Hungary.
The FEBS Journal
|June 19, 2026
Summary
Sorting nexin 21 (Snx21) interacts with flotillins, proteins involved in endocytosis. Snx21 regulates flotillin-mediated trafficking, impacting endosome size and Wingless/Wnt signaling.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Flotillins are key proteins in clathrin-independent endocytosis, implicated in diseases like cancer and neurodegeneration.
- The function of many sorting nexin (Snx) proteins, including Snx21, remains poorly understood.
- Endosomal trafficking is crucial for cellular processes and is often dysregulated in disease.
Purpose of the Study:
- To investigate the function of Snx21 within the endosomal system.
- To determine the relationship between Snx21 and flotillins in endocytic trafficking.
- To explore the role of Snx21 in flotillin-mediated cellular processes.
Main Methods:
- Biochemical assays to detect binding between Snx21 and PI(3)P.
- Confocal microscopy to visualize Snx21 and flotillin localization in Drosophila tissues.
- Genetic manipulation (overexpression and knockdown) to assess functional interactions in vivo.
Main Results:
- Snx21 binds to PI(3)P and localizes to the endosomal system in Drosophila.
- Snx21 physically interacts with and colocalizes with flotillins.
- Snx21 overexpression enlarges late endosomes, a process dependent on Flotillin2.
- Snx21 is required for Wingless/Wnt morphogen accumulation and ectopic wing vein formation induced by Flotillin2 overexpression.
Conclusions:
- Snx21 is identified as a novel binding partner of flotillins.
- Snx21 functions as a positive regulator of flotillin-mediated endocytic trafficking.
- These findings provide new insights into the molecular mechanisms of clathrin-independent endocytosis and its regulation.
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