title: G-proteins in Torpedo marmorata electric organ. Differential distribution in pre- and post-synaptic membranes and synaptic vesicles.
abstract: The nature of the G-proteins present in the pre- and post-synaptic plasma membranes and in the synaptic vesicles of cholinergic nerve terminals purified from the Torpedo electric organ was investigated. In pre- and post-synaptic plasma membranes, Bordetella pertussis toxin, known to catalyze the ADP-ribosylation of the alpha-subunit of several G-proteins, labels two substrates at 41 and 39 kDa. The 39 kDa subunit detected by ADP-ribosylation in the synaptic plasma membrane fractions was immunologically similar to the Go alpha-subunit purified from calf brain. In contrast to bovine chromaffin cell granules, no G-protein could be detected in Torpedo synaptic vesicles either by ADP-ribosylation or by immunoblotting.
mesh_terms: D000313:Adrenal Medulla / Q000032:analysis; D000818:Animals; D002417:Cattle; D004557:Electric Organ / Q000032:analysis*; D019204:GTP-Binding Proteins / Q000032:analysis*; D013569:Synapses / Q000502:physiology; D013570:Synaptic Membranes / Q000032:analysis*; D013572:Synaptic Vesicles / Q000032:analysis*; D014101:Torpedo
chemical_list: D019204:GTP-Binding Proteins