title: Fluorescent false neurotransmitter reveals functionally silent dopamine vesicle clusters in the striatum.
abstract: Neurotransmission at dopaminergic synapses has been studied with techniques that provide high temporal resolution, but cannot resolve individual synapses. To elucidate the spatial dynamics and heterogeneity of individual dopamine boutons, we developed fluorescent false neurotransmitter 200 (FFN200), a vesicular monoamine transporter 2 (VMAT2) substrate that selectively traces monoamine exocytosis in both neuronal cell culture and brain tissue. By monitoring electrically evoked Ca(2+) transients with GCaMP3 and FFN200 release simultaneously, we found that only a small fraction of dopamine boutons that exhibited Ca(2+) influx engaged in exocytosis, a result confirmed with activity-dependent loading of the endocytic probe FM1-43. Thus, only a low fraction of striatal dopamine axonal sites with uptake-competent VMAT2 vesicles are capable of transmitter release. This is consistent with the presence of functionally 'silent' dopamine vesicle clusters and represents, to the best of our knowledge, the first report suggestive of presynaptically silent neuromodulatory synapses.
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, New York, USA.
authors.forename: Daniela B
authors.initials: DB
authors.lastname: Pereira
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, New York, USA.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Schmitz
authors.affiliation: Department of Psychiatry, Columbia University Medical Center, New York, New York, USA.
authors.forename: József
authors.initials: J
authors.lastname: Mészáros
authors.affiliation: Department of Chemistry, Columbia University, New York, New York, USA.
authors.forename: Paolomi
authors.initials: P
authors.lastname: Merchant
authors.affiliation: Department of Chemistry, Columbia University, New York, New York, USA.
authors.forename: Gang
authors.initials: G
authors.lastname: Hu
authors.affiliation: Department of Chemistry, Columbia University, New York, New York, USA.
authors.forename: Shu
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Chemistry, Columbia University, New York, New York, USA.
authors.forename: Adam
authors.initials: A
authors.lastname: Henke
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, New York, USA.
authors.forename: José E
authors.initials: JE
authors.lastname: Lizardi-Ortiz
authors.affiliation: Department of Chemistry, Columbia University, New York, New York, USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Karpowicz
authors.affiliation: Department of Pharmacology, Columbia University Medical Center, New York, New York, USA.
authors.forename: Travis J
authors.initials: TJ
authors.lastname: Morgenstern
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, New York, USA.|Department of Psychiatry, Columbia University Medical Center, New York, New York, USA.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Sonders
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, New York, USA.
authors.forename: Ellen
authors.initials: E
authors.lastname: Kanter
authors.affiliation: Department of Chemistry, Columbia University, New York, New York, USA.
authors.forename: Pamela C
authors.initials: PC
authors.lastname: Rodriguez
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, New York, USA.
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Mosharov
authors.affiliation: Department of Chemistry, Columbia University, New York, New York, USA.
authors.forename: Dalibor
authors.initials: D
authors.lastname: Sames
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, New York, USA.|Department of Psychiatry, Columbia University Medical Center, New York, New York, USA.|Department of Pharmacology, Columbia University Medical Center, New York, New York, USA.|Department of Neuroscience, New York Psychiatric Institute, New York, New York, USA.
authors.forename: David
authors.initials: D
authors.lastname: Sulzer
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003342:Corpus Striatum / Q000737:chemistry / Q000378:metabolism*; D004298:Dopamine / Q000032:analysis / Q000378:metabolism*; D005089:Exocytosis / Q000502:physiology*; D005260:Female; D005456:Fluorescent Dyes / Q000032:analysis / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D018377:Neurotransmitter Agents / Q000032:analysis / Q000378:metabolism; D009924:Organ Culture Techniques; D017729:Presynaptic Terminals / Q000737:chemistry / Q000378:metabolism*; D013572:Synaptic Vesicles / Q000737:chemistry / Q000378:metabolism*
chemical_list: D005456:Fluorescent Dyes; D018377:Neurotransmitter Agents; D004298:Dopamine