CONTROL OF SEX-PHEROMONE BIOSYNTHESIS IN THE MOTH MAMESTRA-BRASSICAE BY THE PHEROMONE BIOSYNTHESIS ACTIVATING NEUROPEPTIDE

The physiological route for the action of the pheromone biosynthesis activating neuropeptide (PBAN) was determined in Mamestra brassicae (L.) (Lepidoptera: Noctuidae). Removal of the ventral nerve cord including the terminal abdominal ganglia did not affect PBAN stimulation of pheromone production and the biogenic amine octopamine did not stimulate pheromone production in isolated abdomens. PBAN-like activity was found in the hemolymph of intact females in scotophase and not in the hemolymph of decapitated females or females in photophase. Our results suggest that PBAN follows a humoral route to its site of action rather than a neural one after being released from the brain. The hormonal control of the pheromone biosynthetic pathway was investigated using labeled precursors. Our results suggest that PBAN regulates an early step in the pheromone biosynthetic pathway, contrary to a previous report that it stimulates the Delta 11-desaturase.