Recruitment of clathrin to intracellular membranes is sufficient for vesicle formation
Abstract
The formation of a clathrin-coated vesicle is a major membrane remodeling process that is crucial for membrane traffic in cells. Besides clathrin, these vesicles contain at least 100 different proteins although it is unclear how many are essential for the formation of the vesicle. Here, we show that intracellular clathrin-coated formation can be induced in living cells using minimal machinery and that it can be achieved on various membranes, including the mitochondrial outer membrane. Chemical heterodimerization was used to inducibly attach a clathrin-binding fragment 'hook' to an 'anchor' protein targeted to a specific membrane. Endogenous clathrin assembled to form coated pits on the mitochondria, termed MitoPits, within seconds of induction. MitoPits are double-membraned invaginations that form preferentially on high curvature regions of the mitochondrion. Upon induction, all stages of CCV formation - initiation, invagination, and even fission - were faithfully reconstituted. We found no evidence for the functional involvement of accessory proteins in this process. In addition, fission of MitoPit-derived vesicles was independent of known scission factors including dynamins and dynamin-related protein 1 (Drp1), suggesting that the clathrin cage generates sufficient force to bud intracellular vesicles. Our results suggest that, following its recruitment, clathrin is sufficient for intracellular clathrin-coated vesicle formation.
Data availability
Data and code associated with this study are available at https://github.com/quantixed/p057p034 (Royle, 2022).
Article and author information
Author details
Funding
UK Research and Innovation (EP/L016494/1)
- Cansu Küey
UK Research and Innovation (BB/V003062/1)
- Méghane Sittewelle
- Stephen J Royle
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Küey 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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