A PX-BAR protein Mvp1/SNX8 and a dynamin-like GTPase Vps1 drive endosomal recycling
Abstract
Membrane protein recycling systems are essential for maintenance of the endosome-lysosome system. In yeast, retromer and Snx4 coat complexes are recruited to the endosomal surface where they recognize cargos. They sort cargo and deform the membrane into recycling tubules that bud from the endosome and target to the Golgi. Here, we reveal that the SNX-BAR protein, Mvp1, mediates an endosomal recycling pathway which is mechanistically distinct from the retromer and Snx4 pathways. Mvp1 deforms the endosomal membrane and sorts cargos containing a specific sorting motif into a membrane tubule. Subsequently, Mvp1 recruits the dynamin-like GTPase Vps1 to catalyze membrane scission and release of the recycling tubule. Similarly, SNX8, the human homolog of Mvp1, which has been also implicated in Alzheimer's disease, mediates formation of an endosomal recycling tubule. Thus, we present evidence for a novel endosomal retrieval pathway that is conserved from yeast to humans.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files
Article and author information
Author details
Funding
Cornell University Research Grant (CU3704)
- Scott D Emr
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Suzanne R Pfeffer, Stanford University School of Medicine, United States
Version history
- Preprint posted: March 11, 2021 (view preprint)
- Received: April 28, 2021
- Accepted: September 14, 2021
- Accepted Manuscript published: September 15, 2021 (version 1)
- Version of Record published: October 11, 2021 (version 2)
Copyright
© 2021, Suzuki et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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