title: On the structure of the 'synaptosecretosome'. Evidence for a neurexin/synaptotagmin/syntaxin/Ca2+ channel complex.
abstract: Recent experiments have identified interactions between presynaptic and synaptic vesicle membrane proteins, that might be important in organizing the components of the fast neurotransmitter release mechanism to ensure that the process follows a rapid time course. Here we extend previous investigations to show that in addition to the alpha-latrotoxin receptor (neurexin) and synaptotagmin another presynaptic protein, syntaxin, co-purifies on a alpha-latrotoxin affinity column. This implies that syntaxin is associated with these two molecules in a complex; a conclusion supported by the immunoprecipitation of [125I]latrotoxin binding by syntaxin antibodies. In addition, antibodies against syntaxin and the alpha-latrotoxin receptor immunoprecipitate [125I]omega-conotoxin binding sites, indicating that calcium channels are associated with this complex. Thus, neurexin, synaptotagmin, syntaxin, and calcium channels can be found in a structure we propose to call the 'synaptosecretosome'. The components of the synaptosecretosome, in association with additional proteins, are postulated to organize the process of neurotransmitter release.
authors.affiliation: Abteilung Neurochemie, Max-Planck-Institut für Hirnforschung, Frankfurt am Main, Germany.
authors.forename: V M
authors.initials: VM
authors.lastname: O'Connor
authors.forename: O
authors.initials: O
authors.lastname: Shamotienko
authors.forename: E
authors.initials: E
authors.lastname: Grishin
authors.forename: H
authors.initials: H
authors.lastname: Betz
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis / Q000378:metabolism*; D001921:Brain / Q000648:ultrastructure; D001923:Brain Chemistry; D015220:Calcium Channels / Q000378:metabolism*; D002135:Calcium-Binding Proteins; D002462:Cell Membrane / Q000737:chemistry; D002499:Centrifugation, Density Gradient; D002846:Chromatography, Affinity; D007163:Immunosorbent Techniques; D008562:Membrane Glycoproteins / Q000032:analysis / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000378:metabolism*; D018377:Neurotransmitter Agents / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D051381:Rats; D011950:Receptors, Cholinergic / Q000032:analysis / Q000378:metabolism*; D018000:Receptors, Peptide; D013111:Spider Venoms; D013572:Synaptic Vesicles / Q000378:metabolism* / Q000648:ultrastructure; D050857:Synaptotagmins; D050827:Syntaxin 1; D020960:omega-Conotoxins
chemical_list: D000954:Antigens, Surface; D015220:Calcium Channels; D002135:Calcium-Binding Proteins; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D018377:Neurotransmitter Agents; D010455:Peptides; D011950:Receptors, Cholinergic; D018000:Receptors, Peptide; D013111:Spider Venoms; D050827:Syntaxin 1; C034800:alpha-latrotoxin receptor; D020960:omega-Conotoxins; C053423:Conus magus toxin; D050857:Synaptotagmins; C020763:alpha-latrotoxin