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A dual role for ?-synuclein in facilitation and depression of dopamine release from substantia nigra neurons in vivo.

ABSTRACT: ?-Synuclein is expressed at high levels at presynaptic terminals, but defining its role in the regulation of neurotransmission under physiologically relevant conditions has proven elusive. We report that, in vivo, ?-synuclein is responsible for the facilitation of dopamine release triggered by action potential bursts separated by short intervals (seconds) and a depression of release with longer intervals between bursts (minutes). These forms of presynaptic plasticity appear to be independent of the presence of ?- and ?-synucleins or effects on presynaptic calcium and are consistent with a role for synucleins in the enhancement of synaptic vesicle fusion and turnover. These results indicate that the presynaptic effects of ?-synuclein depend on specific patterns of neuronal activity.

SUBMITTER: Somayaji M

PROVIDER: S-EPMC7768743 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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A dual role for α-synuclein in facilitation and depression of dopamine release from substantia nigra neurons in vivo.

Somayaji Mahalakshmi M Cataldi Stefano S Choi Se Joon SJ Edwards Robert H RH Mosharov Eugene V EV Sulzer David D

Proceedings of the National Academy of Sciences of the United States of America 20201203 51

α-Synuclein is expressed at high levels at presynaptic terminals, but defining its role in the regulation of neurotransmission under physiologically relevant conditions has proven elusive. We report that, in vivo, α-synuclein is responsible for the facilitation of dopamine release triggered by action potential bursts separated by short intervals (seconds) and a depression of release with longer intervals between bursts (minutes). These forms of presynaptic plasticity appear to be independent of ...[more]

PMID: 33273122

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