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Ultrastructural localization of mint1 at synapses in mouse hippocampus
Author(s) -
Okamoto Masaya,
Matsuyama Tomohiro,
Sugita Minoru
Publication year - 2000
Publication title -
european journal of neuroscience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.346
H-Index - 206
eISSN - 1460-9568
pISSN - 0953-816X
DOI - 10.1046/j.1460-9568.2000.00200.x
Subject(s) - biology , synapse , synaptic vesicle , neuroscience , postsynaptic potential , postsynaptic density , microbiology and biotechnology , immunolabeling , hippocampus , inhibitory postsynaptic potential , vesicle , excitatory postsynaptic potential , receptor , biochemistry , immunohistochemistry , membrane , immunology
Mint1 and mint2 were isolated in the course of seeking the protein ligands to munc18–1, a neuronal protein essential for synaptic vesicle exocytosis. The mint family of proteins has been highly conserved in the course of evolution, being retained from C. elegans to mammals. Several lines of biochemical and genetic evidence have suggested that mint1 and LIN‐10, its homologue in C. elegans, function at synapses in the brain. Because the precise subcellular location of mint1 is incompletely known, we used immunostaining to examine the distribution of mint1 in the mouse brain including ultrastructural localization in synapses. Strong, finely punctate mint1 immunolabeling was detected throughout the brain, including cerebral cortex, striatum, hippocampus, thalamus, basal ganglia and cerebellum. At the most synapses in the molecular layer, mint1 was particularly abundant at the active zone and to a lesser extent in association with synaptic vesicles in the presynaptic terminals. In contrast, a very few synapses showed mint1 immunoreactivity in the postsynaptic density and there was no synapse double‐positive in presynaptic and postsynaptic terminals. Mint1 distribution within presynaptic terminals overlapped that of munc18–1. These localization results are consistent with previously demonstrated biochemical interactions and strongly support functions of mint1 in synaptic vesicle exocytosis and synaptic organization in the central nervous system.