PHEROMONE-INDUCED PHOSPHORYLATION OF ANTENNAL PROTEINS FROM INSECTS

Protein kinase C inhibitors, such a calphostin C, abolish the transien t nature of pheromone-induced rapid inositol 1,4,5-triphosphate (IP3) responses, suggesting that pheromone signalling is terminated by phosp horylation of specific proteins. Challenging antennal preparations fro m Heliothis virescens with species-specific pheromones in the presence of [P-32]-gamma-ATP led to a rapid, stimulus-dependent incorporation of P-32(i) into antennal proteins. Pheromone-induced phosphorylation w as completely abolished by a blockade of protein kinase C. Electrophor etic analysis revealed that upon stimulation with a pheromone blend tw o polypeptide bands were labelled; stimulation solely with the major c ompound (Z-11-hexadecenal) resulted in only a single labelled band. Th e data indicate that pheromones cause phosphorylation of specific ante nnal proteins which may be receptors for pheromones.