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Updated: Oct 20, 2026

Density Gradient Ultracentrifugation for Investigating Endocytic Recycling in Mammalian Cells
Published on: June 30, 2021
ARF-1 coordinates cargo sorting at FERARI endosomal recycling hubs
Jachen A Solinger1, Curdin A Franziscus1, Trian Nuredini1
1Biozentrum, University of Basel , Basel, Switzerland.
Abstract:
Endosomal pathways are central to cellular organization, compartmentalization, and intercellular communication. Independent of the endocytic entry route, sorting endosomes function as critical junctions at which membrane proteins are sorted for recycling or degradation. The multicomponent tether FERARI orchestrates recycling by coordinating Rab GTPase activity with vesicle fusion and fission through a kiss-and-run (KAR) mechanism. Here, we identify the small GTPase ARF-1 as an essential regulator of cargo loading at FERARI-dependent endosomal KAR sites. Cycling of ARF-1 between its active and inactive states is required for efficient cargo capture into recycling vesicles. Our findings support a model in which cycling ARF-1 activity governs the temporal association of cargo with adaptor proteins and complexes, thereby controlling selective uptake into vesicles destined for the plasma membrane. These results uncover a previously unappreciated layer of regulation of endosomal recycling and highlight the interplay between ARF and Rab family GTPases in this process.
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