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PubMed · 15157422

Postfusional control of quantal current shape.

Christian Pawlu·Aaron DiAntonio·Manfred Heckmann
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Abstract

Whether glutamate is released rapidly, in an all-or-none manner, or more slowly, in a regulated manner, is a matter of debate. We analyzed the time course of excitatory postsynaptic currents (EPSCs) at glutamatergic neuromuscular junctions of Drosophila and found that the decay phase of EPSCs was protracted to a variable extent. The protraction was more pronounced in evoked and spontaneous quantal EPSCs than in action potential-evoked multiquantal EPSCs; reduced in quantal EPSCs from endophilin null mutants, which maintain release via kiss-and-run; and dependent on synaptotagmin isoform, calcium, and protein phosphorylation. Our data indicate that glutamate is released from individual synaptic vesicles for milliseconds through a fusion pore. Quantal glutamate discharge time course depends on presynaptic calcium inflow and the molecular composition of the release machinery.

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Action PotentialsAdaptor Proteins, Signal TransducingAnimalsCalcium SignalingCalcium-Binding ProteinsCarrier ProteinsDrosophila melanogasterExcitatory Postsynaptic PotentialsGlutamic AcidLarvaMembrane FusionMembrane GlycoproteinsNerve Tissue ProteinsNeuromuscular JunctionPhosphorylationSynaptic MembranesSynaptic TransmissionSynaptic VesiclesSynaptotagminsTime FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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Christian Pawlu, Aaron DiAntonio, Manfred Heckmann. 2004-05-27. Postfusional control of quantal current shape.. https://doi.org/10.1016/s0896-6273(04)00269-7

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