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Published on: March 26, 2014
Effects of proteasome inhibitors on the synaptic localization of Vesl-1S/Homer-1a proteins
1Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
Abstract:
The Vesl-1S/Homer-1a proteins are upregulated during seizure and long-term potentiation, but are rapidly degraded by ubiquitin-proteasome systems under normal conditions. We examined the distribution of Vesl-1S proteins in cultured hippocampal neurons. Application of proteasome inhibitors caused accumulation of Vesl-1S immunoreactivity in the neurons which showed a punctate distribution in the cortical regions of the cells, and these puncta were found to be juxtaposed with synaptophysin, a presynaptic, synapse-specific protein. These results suggest that Vesl-1S protein is synaptically targeted.
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