Nanodomain coupling explains Ca^2+ independence of transmitter release time course at a fast central synapse Journal Article


Author(s): Arai, Itaru; Jonas, Peter
Article Title: Nanodomain coupling explains Ca^2+ independence of transmitter release time course at a fast central synapse
Affiliation IST Austria
Abstract: A puzzling property of synaptic transmission, originally established at the neuromuscular junction, is that the time course of transmitter release is independent of the extracellular Ca2+ concentration ([Ca2+]o), whereas the rate of release is highly [Ca2+]o-dependent. Here, we examine the time course of release at inhibitory basket cell-Purkinje cell synapses and show that it is independent of [Ca2+]o. Modeling of Ca2+-dependent transmitter release suggests that the invariant time course of release critically depends on tight coupling between Ca2+ channels and release sensors. Experiments with exogenous Ca2+ chelators reveal that channel-sensor coupling at basket cell-Purkinje cell synapses is very tight, with a mean distance of 10–20 nm. Thus, tight channel-sensor coupling provides a mechanistic explanation for the apparent [Ca2+]o independence of the time course of release.
Keywords: mouse; Ca2+ channels; GABAergic synapses; cerebellar basket cells; nanodomain coupling; neuroscience; release sensors; time course of transmitter release
Journal Title: eLife
Volume: 3
ISSN: 2050-084X
Publisher: eLife Sciences Publications  
Date Published: 2014-12-09
Start Page: e04057
Copyright Statement: CC-BY
Sponsor: Austrian Science Fund P 24909-B24 and European Research Council Advanced Grant 268548, Peter Jonas
URL:
DOI: 10.7554/eLife.04057
Open access: yes (OA journal)