Capping protein regulates endosomal trafficking by controlling F-actin density around endocytic vesicles and recruiting RAB5 effectors
- City University of Hong Kong, China
- Southern University of Science and Technology, China
Abstract
Actin filaments (F-actin) have been implicated in various steps of endosomal trafficking, and the length of F-actin is controlled by actin capping proteins, such as CapZ, which is a stable heterodimeric protein complex consisting of a and β subunits. However, the role of these capping proteins in endosomal trafficking remains elusive. Here, we found that CapZ docks to endocytic vesicles via its C-terminal actin-binding motif. CapZ knockout significantly increases the F-actin density around immature early endosomes, and this impedes fusion between these vesicles, manifested by the accumulation of small endocytic vesicles in CapZ-knockout cells. CapZ also recruits several RAB5 effectors, such as Rabaptin-5, to RAB5-positive early endosomes via its N-terminal domain, and this further activates RAB5. Collectively, our results indicate that CapZ regulates endosomal trafficking by controlling actin density around early endosomes and recruiting RAB5 effectors.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Funding
Research Grants Council, University Grants Committee (11101717)
- Jianbo Yue
Research Grants Council, University Grants Committee (11103620)
- Jianbo Yue
National Natural Science Foundation of China (21778045)
- Jianbo Yue
National Natural Science Foundation of China (2070702)
- Jianbo Yue
Science, Technology and Innovation Commission of Shenzhen Municipality (JCYJ20160229165235739)
- Jianbo Yue
Science, Technology and Innovation Commission of Shenzhen Municipality (JCYJ20170413141331470)
- Jianbo Yue
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Wang 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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Capping protein regulates endosomal trafficking by controlling F-actin density around endocytic vesicles and recruiting RAB5 effectors
eLife 10:e65910.
https://doi.org/10.7554/eLife.65910
Further reading
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