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bioRxiv · 10.1101/2020.06.10.145110

α-Synuclein facilitates dopamine release during burst firing of substantia nigra neurons in vivo

Somayaji, M.·Cataldi, S.·Edwards, R. H.·Mosharov, E. V.·Sulzer, D.
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Abstract

-Synuclein is expressed at high levels at presynaptic terminals, but defining its role on neurotransmission under physiologically-relevant conditions has proven elusive. We report that -synuclein is responsible for a rapid facilitation of dopamine release during action potential bursts in vivo. This occurs in tandem with a far slower stimulus-dependent depression, appears to be independent of the presence of {beta}- and {gamma}-synucleins or effects on presynaptic calcium and is consistent with a role for synucleins in the enhancement of synaptic vesicle fusion and turnover. The results indicate that the presynaptic effects of -synuclein are dependent on specific patterns of neuronal activity.

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Somayaji, M., Cataldi, S., Edwards, R. H., Mosharov, E. V., Sulzer, D.. 2020-06-12. α-Synuclein facilitates dopamine release during burst firing of substantia nigra neurons in vivo. https://doi.org/10.1101/2020.06.10.145110

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