Daniels, R.W. et al. Increased expression of the Drosophila vesicular glutamate transporter leads to excess glutamate release and a compensatory decrease in quantal content. J. Neurosci. 24, 10466-10474

Department of Molecular Biology and Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.34). 12/2004; 24(46):10466-74. DOI: 10.1523/JNEUROSCI.3001-04.2004
Source: PubMed


Quantal size is a fundamental parameter controlling the strength of synaptic transmission. The transmitter content of synaptic vesicles is one mechanism that can affect the physiological response to the release of a single vesicle. At glutamatergic synapses, vesicular glutamate transporters (VGLUTs) are responsible for filling synaptic vesicles with glutamate. To investigate how VGLUT expression can regulate synaptic strength in vivo, we have identified the Drosophila vesicular glutamate transporter, which we name DVGLUT. DVGLUT mRNA is expressed in glutamatergic motoneurons and a large number of interneurons in the Drosophila CNS. DVGLUT protein resides on synaptic vesicles and localizes to the presynaptic terminals of all known glutamatergic neuromuscular junctions as well as to synapses throughout the CNS neuropil. Increasing the expression of DVGLUT in motoneurons leads to an increase in quantal size that is accompanied by an increase in synaptic vesicle volume. At synapses confronted with increased glutamate release from each vesicle, there is a compensatory decrease in the number of synaptic vesicles released that maintains normal levels of synaptic excitation. These results demonstrate that (1) expression of DVGLUT determines the size and glutamate content of synaptic vesicles and (2) homeostatic mechanisms exist to attenuate the excitatory effects of excess glutamate release.

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Available from: Richard W Daniels, Jun 20, 2014
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    • "Flies expressing E1 RNAi and DVMAT-pHluorin were generated as described in (Martin et al., 2014) and (Grygoruk et al., 2014), respectively, and are available on request. Other lines including elav-GAL4(X) (Robinow and White, 1991), Tdc2-GAL4 (Cole et al., 2005), DVGLUT-GAL4 (Daniels et al., 2004), UAS-Arclight (Cao et al., 2013) and UAS- GCaMP6m(III) (Chen et al., 2013) are available from the "
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    • "The vesicular glutamate transporters are important for the storage and release of the excitatory neurotransmitter glutamate at presynaptic axon terminals (Ni et al. 1994; Bellocchio et al. 2000; Takamori et al. 2000; Herzog et al. 2001; Gras et al. 2002; Schäfer et al. 2002). In addition to a third subtype (VGLUT-3), they belong to the Slc17 family (solute carrier family) of proteins which are highly conserved in nature and found in organisms as diverse as drosophila, zebra fish, frogs, and mammals (Daniels et al. 2004; Higashijima et al. 2004, Gleason et al. 2003). The presence of the vesicular glutamate transporters is an important diagnostic for identifying glutamatergic synapses and therefore, for excitatory projections in the brain. "
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