The role of scaffold reshaping and disassembly in dynamin driven membrane fission
Abstract
The large GTPase dynamin catalyzes membrane fission in eukaryotic cells, but despite three decades of experimental work, competing and partially conflicting models persist regarding some of its most basic actions. Here we investigate the mechanical and functional consequences of dynamin scaffold shape changes and disassembly with the help of a geometrically and elastically realistic simulation model of helical dynamin-membrane complexes. Beyond changes of radius and pitch, we emphasize the crucial role of a third functional motion: an effective rotation of the filament around its longitudinal axis, which reflects alternate tilting of dynamin's PH binding domains and creates a membrane torque. We also show that helix elongation impedes fission, hemifission is reached via a small transient pore, and coat disassembly assists fission. Our results have several testable structural consequences and help to reconcile mutual conflicting aspects between the two main present models of dynamin fission-the two-stage and the constrictase model.
Data availability
The simulation software used is freely available at http://espressomd.org/wordpress/. Source data for Figure 2F, the supplement figure to Figure 2F, Figure 3, and Figure 6 are also provided.
Article and author information
Author details
Funding
National Science Foundation (NSF CHE #1464926)
- Markus Deserno
Carnegie Mellon University (Center of Excellence funding)
- Markus Deserno
European Union Horizon 2020 Research and Innovation Program (Marie Sklodowska-Curie grant agreement no. 754490)
- Martina Pannuzzo
National Science Foundation (NSF CHE #1764257)
- Markus Deserno
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Pannuzzo 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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