Epsin deficiency impairs endocytosis by stalling the actin-dependent invagination of endocytic clathrin-coated pits
Abstract
Epsin is an evolutionarily conserved endocytic clathrin adaptor whose most critical function(s) in clathrin coat dynamics remain(s) elusive. To elucidate such function(s), we generated embryonic fibroblasts from conditional epsin triple KO mice. Triple KO cells displayed a dramatic cell division defect. Additionally, a robust impairment in clathrin-mediated endocytosis was observed, with an accumulation of early and U-shaped pits. This defect correlated with a perturbation of the coupling between the clathrin coat and the actin cytoskeleton, which we confirmed in a cell-free assay of endocytosis. Our results indicate that a key evolutionary conserved function of epsin, in addition to other roles that include as we show here a low affinity interaction with SNAREs, is to help generate the force that leads to invagination and then fission of clathrin-coated pits.
Article and author information
Author details
Reviewing Editor
- Suzanne R Pfeffer, Stanford University, United States
Ethics
Animal experimentation: The institutional animal care and use committee (IACUC) of the Yale University and the approved animal protocol is 2012-07422. The institutional guidelines for the care and use of laboratory animals were followed
Version history
- Received: May 7, 2014
- Accepted: August 12, 2014
- Accepted Manuscript published: August 13, 2014 (version 1)
- Version of Record published: September 12, 2014 (version 2)
Copyright
© 2014, Messa 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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