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Visualizing Clathrin-mediated Endocytosis of G Protein-coupled Receptors at Single-event Resolution via TIRF Microscopy
Published on: October 20, 2014
Endofin recruits TOM1 to endosomes
Li-Fong Seet1, Ningsheng Liu, Brendon J Hanson
1Membrane Biology Laboratory, Institute of Molecular and Cell Biology, Singapore 117609, Singapore. mcbslf@imcb.a-star.edu.sg
The Journal of Biological Chemistry
|November 14, 2003
Summary
Endofin binds to TOM1, a protein previously uncharacterized in its cellular location or function. This interaction suggests TOM1 acts as an effector for endofin, potentially playing a role in endosomal trafficking.
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Interactions
Background:
- Endofin is an endosomal protein regulating membrane trafficking, featuring a FYVE domain.
- The function and localization of TOM1, a protein related to the GGA family, are unknown.
Purpose of the Study:
- To identify endofin binding partners.
- To elucidate the subcellular localization and function of TOM1.
Main Methods:
- Yeast two-hybrid screening using endofin's carboxyl-terminal half.
- Glutathione S-transferase pull-down and co-immunoprecipitation assays.
- Immunofluorescence and sucrose density gradient analyses.
Main Results:
- Endofin's carboxyl-terminal half specifically binds to TOM1's carboxyl-terminal region.
- TOM1 is primarily cytosolic but localizes to early endosomes with endofin.
- Overexpression of endofin recruits TOM1 to endosomes.
Conclusions:
- TOM1 is identified as an effector of endofin.
- The findings suggest a role for TOM1 in endosomal trafficking.
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