Developmental regulation of the pheromone biosynthesis activating neuropeptide-receptor (PBAN-R): re-evaluating the role of juvenile hormone

Authors


Ada Rafaeli, Institute for Technology and Storage of Agricultural Products, Volcani Center, ARO, P.O. Box 6, Bet-Dagan 50250, Israel. Tel.: + 972 3 9683729; fax: + 972 3 9604428; e-mail: vtada@volcani.agri.gov.il

Abstract

Sex pheromone production in Helicoverpa armigera is regulated by pheromone-biosynthesis-activating neuropeptide (PBAN), which binds to a G-protein coupled receptor at the pheromone gland. We demonstrate the temporal differential expression levels of the PBAN receptor (PBAN-R) gene, reaching peak levels at a critical period of 5 h post-eclosion. Previous studies implied a possible regulatory role for juvenile hormone (JH). We herein demonstrate that PBAN-R expression levels increase normally when females are decapitated or head-ligated, removing the source of JH, before peak transcript levels are reached. Similarly, sex pheromone production can be induced by PBAN in such decapitated females. These results indicate that up-regulation, at this critical time, is not dependent on JH originating from the head. Conversely, JH injected in vivo at this critical period significantly inhibits PBAN-R transcript levels.

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