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SUMOylation of Syntaxin1A regulates presynaptic endocytosis.

ABSTRACT: Neurotransmitter release from the presynaptic terminal is under very precise spatial and temporal control. Following neurotransmitter release, synaptic vesicles are recycled by endocytosis and refilled with neurotransmitter. During the exocytosis event leading to release, SNARE proteins provide most of the mechanical force for membrane fusion. Here, we show one of these proteins, Syntaxin1A, is SUMOylated near its C-terminal transmembrane domain in an activity-dependent manner. Preventing SUMOylation of Syntaxin1A reduces its interaction with other SNARE proteins and disrupts the balance of synaptic vesicle endo/exocytosis, resulting in an increase in endocytosis. These results indicate that SUMOylation regulates the emerging role of Syntaxin1A in vesicle endocytosis, which in turn, modulates neurotransmitter release and synaptic function.

SUBMITTER: Craig TJ

PROVIDER: S-EPMC4669484 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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SUMOylation of Syntaxin1A regulates presynaptic endocytosis.

Craig Tim J TJ Anderson Dina D Evans Ashley J AJ Girach Fatima F Henley Jeremy M JM

Scientific reports 20151204

Neurotransmitter release from the presynaptic terminal is under very precise spatial and temporal control. Following neurotransmitter release, synaptic vesicles are recycled by endocytosis and refilled with neurotransmitter. During the exocytosis event leading to release, SNARE proteins provide most of the mechanical force for membrane fusion. Here, we show one of these proteins, Syntaxin1A, is SUMOylated near its C-terminal transmembrane domain in an activity-dependent manner. Preventing SUMOyl ...[more]

PMID: 26635000

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