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Role of beta-catenin in synaptic vesicle localization and presynaptic assembly.

ABSTRACT: Cadherins and catenins are thought to promote adhesion between pre and postsynaptic elements in the brain. Here we show a role for beta-catenin in localizing the reserved pool of vesicles at presynaptic sites. Deletion of beta-catenin in hippocampal pyramidal neurons in vivo resulted in a reduction in the number of reserved pool vesicles per synapse and an impaired response to prolonged repetitive stimulation. This corresponded to a dispersion of vesicles along the axon in cultured neurons. Interestingly, these effects are not due to beta-catenin's involvement in cadherin-mediated adhesion or wnt signaling. Instead, beta-catenin modulates vesicle localization via its PDZ binding domain to recruit PDZ proteins such as Veli to cadherin at synapses. This study defines a specific role for cadherins and catenins in synapse organization beyond their roles in mediating cell adhesion.

SUBMITTER: Bamji SX

PROVIDER: S-EPMC2757419 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature

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Role of beta-catenin in synaptic vesicle localization and presynaptic assembly.

Bamji Shernaz X SX Shimazu Kazuhiro K Kimes Nikole N Huelsken Joerg J Birchmeier Walter W Lu Bai B Reichardt Louis F LF

Neuron 20031101 4

Cadherins and catenins are thought to promote adhesion between pre and postsynaptic elements in the brain. Here we show a role for beta-catenin in localizing the reserved pool of vesicles at presynaptic sites. Deletion of beta-catenin in hippocampal pyramidal neurons in vivo resulted in a reduction in the number of reserved pool vesicles per synapse and an impaired response to prolonged repetitive stimulation. This corresponded to a dispersion of vesicles along the axon in cultured neurons. Inte ...[more]

PMID: 14622577

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