Pheromone-induced stimulation of inositol-trisphosphate formation in insect antennae is mediated by G-proteins

Summary Phospholipase C in the antennae of Periplaneta americana was stimulated by pheromones in a GTP-dependent manner. The enzyme activity was potentiated by hydrolysis-resistant analogs of GTP and decreased by GDP analogs. Guanine nucleotide binding regulatory proteins (G-proteins) in antennal preparations were identified by bacterial toxin-catalyzed ADP-ribosylation and immunoreactivity with antibodies of designed specificity. The stimulatory effect of pheromones on inositol phosphate formation was completely blocked by pertussis toxin suggesting that the pheromone action was mediated via specific G-proteins.Abbreviations G-protein guanine nucleotide-binding regulatory protein - IP ₃ inositol 1,4,5-trisphosphate - GTPS guanine-5-thio]-triphosphate - GDPS guanine-5--thio]-diphosphate - NAD nicotinic acid adenine dinucleotide - SDS-PAGE sodium dodecylsulfate polyacrylamide gel electrophoresis - DTT dithiothreitol - MOPS 3-(N-morpholino)propanesulfonic acid - PIPES piperazine-N,N-bis2-ethanesulfonic acid] - DMSO dimethyl-sulfoxide