Retriever fetches integrins from endosomes.
1Hubrecht Institute/KNAW and UMC Utrecht, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; and the Department of Cell Biology, UMC Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
Nature Cell Biology
|September 30, 2017
Summary
A newly discovered protein complex, retriever, works with SNX17 and WASH to recycle key cell receptors. This finding advances understanding of cell homeostasis and protein trafficking pathways.
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Trafficking
Background:
- Cellular homeostasis relies on efficient recycling of proteins from endosomes to the plasma membrane.
- The retromer/SNX27/WASH complex is known to mediate recycling of various receptors.
- However, the mechanisms for recycling certain key receptors remain incompletely understood.
Purpose of the Study:
- To identify novel protein complexes involved in endosomal recycling.
- To elucidate the role of these complexes in the trafficking of specific cell surface receptors.
Main Methods:
- Proteomic analysis to identify novel protein complexes.
- Biochemical assays to confirm protein interactions.
- Cell-based assays to study receptor recycling pathways.
Main Results:
- Identification of a conserved heterotrimeric complex named 'retriever'.
- Demonstration that retriever, in conjunction with SNX17, the CCC complex, and WASH, mediates the recycling of α5β1 integrins.
- This pathway accounts for the recycling of previously uncharacterized key receptors.
Conclusions:
- The retriever complex is a crucial component of the endosomal recycling machinery.
- This discovery expands the known pathways for receptor trafficking and contributes to understanding cell homeostasis.
- Further research into the retriever complex may reveal new therapeutic targets for diseases involving protein mis-trafficking.
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