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Synapsins and the Synaptic Vesicle Reserve Pool: Floats or Anchors?

ABSTRACT: In presynaptic terminals, synaptic vesicles (SVs) are found in a discrete cluster that includes a reserve pool that is mobilized during synaptic activity. Synapsins serve as a key protein for maintaining SVs within this reserve pool, but the mechanism that allows synapsins to do this is unclear. This mechanism is likely to involve synapsins either cross-linking SVs, thereby anchoring SVs to each other, or creating a liquid phase that allows SVs to float within a synapsin droplet. Here, we summarize what is known about the role of synapsins in clustering of SVs and evaluate experimental evidence supporting these two models.

SUBMITTER: Zhang M

PROVIDER: S-EPMC8002314 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Synapsins and the Synaptic Vesicle Reserve Pool: Floats or Anchors?

Zhang Minchuan M Augustine George J GJ

Cells 20210316 3

In presynaptic terminals, synaptic vesicles (SVs) are found in a discrete cluster that includes a reserve pool that is mobilized during synaptic activity. Synapsins serve as a key protein for maintaining SVs within this reserve pool, but the mechanism that allows synapsins to do this is unclear. This mechanism is likely to involve synapsins either cross-linking SVs, thereby anchoring SVs to each other, or creating a liquid phase that allows SVs to float within a synapsin droplet. Here, we summar ...[more]

PMID: 33809712

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