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Bassoon speeds vesicle reloading at a central excitatory synapse.

ABSTRACT: Sustained rate-coded signals encode many types of sensory modalities. Some sensory synapses possess specialized ribbon structures, which tether vesicles, to enable high-frequency signaling. However, central synapses lack these structures, yet some can maintain signaling over a wide bandwidth. To analyze the underlying molecular mechanisms, we investigated the function of the active zone core component Bassoon in cerebellar mossy fiber to granule cell synapses. We show that short-term synaptic depression is enhanced in Bassoon knockout mice during sustained high-frequency trains but basal synaptic transmission is unaffected. Fluctuation and quantal analysis as well as quantification with constrained short-term plasticity models revealed that the vesicle reloading rate was halved in the absence of Bassoon. Thus, our data show that the cytomatrix protein Bassoon speeds the reloading of vesicles to release sites at a central excitatory synapse.

SUBMITTER: Hallermann S

PROVIDER: S-EPMC3004039 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Bassoon speeds vesicle reloading at a central excitatory synapse.

Hallermann Stefan S Fejtova Anna A Schmidt Hartmut H Weyhersmüller Annika A Silver R Angus RA Gundelfinger Eckart D ED Eilers Jens J

Neuron 20101101 4

Sustained rate-coded signals encode many types of sensory modalities. Some sensory synapses possess specialized ribbon structures, which tether vesicles, to enable high-frequency signaling. However, central synapses lack these structures, yet some can maintain signaling over a wide bandwidth. To analyze the underlying molecular mechanisms, we investigated the function of the active zone core component Bassoon in cerebellar mossy fiber to granule cell synapses. We show that short-term synaptic de ...[more]

PMID: 21092860

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