Synaptic F-actin network controls otoferlin-dependent exocytosis in auditory inner hair cells
- Université de Bordeaux, France
- Institut Pasteur, France
Abstract
We show that a cage-shaped F-actin network is essential for maintaining a tight spatial organization of Cav1.3 Ca2+ channels at the synaptic ribbons of auditory inner hair cells. This F-actin network is also found to provide mechanosensitivity to the Cav1.3 channels when varying intracellular hydrostatic pressure. Furthermore, this F-actin mesh network attached to the synaptic ribbons directly influences the efficiency of otoferlin-dependent exocytosis and its sensitivity to intracellular hydrostatic pressure, independently of its action on the Cav1.3 channels. We propose a new mechanistic model for vesicle exocytosis in auditory hair cells where the rate of vesicle recruitment to the ribbons is directly controlled by a synaptic F-actin network and changes in intracellular hydrostatic pressure.
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Animal experimentation: This study was performed in accordance with the guidelines of the Animal Care Committee of the European Communities Council Directive (86/609/EEC) and were approved by the ethics committee of the University of Bordeaux (animal facility agreement 155 number C33-063-075)
Copyright
© 2015, Vincent 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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Synaptic F-actin network controls otoferlin-dependent exocytosis in auditory inner hair cells
eLife 4:e10988.
https://doi.org/10.7554/eLife.10988
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