1a. Objectives (from AD-416):
The objective of this proposed project is to characterize proteins (odorant receptors, odorant binding proteins and odorant degrading enzymes), and the gene transcripts that encode them to increase our knowledge of how the codling moth olfactory system works to detect codlemone at the cellular level.
1b. Approach (from AD-416):
1) We will express and characterize proteins predicted to be involved in codlemone detection. This will include odorant binding proteins, nerve membrane receptors, and odorant degrading enzymes. 2) We will determine which odorant binding proteins, nerve membrane receptors, and odorant degrading enzymes are involved in the codlemone signaling pathway using in vitro protein expression and binding assays. 3) We will determine where codlemone reactive proteins are expressed in antennae using fluorescent in situ hybridization and immunofluorescent detection methods. 4) We will determine if codlemone signaling can disrupted using various odorant degrading enzyme inhibitors (many of which are commercially available) in flight tunnel studies.
3. Progress Report:
Insect mating is preceded by chemical attraction to the opposite sex, a process which relies heavily on an acute olfactory system. The goal of this project is to determine which olfactory proteins are involved in codling moth pheromone perception, and to exploit this information to develop more potent semiochemicals that can be used in codling moth control programs. We have identified gene transcripts encoding the major proteins thought to be involved in pheromone perception and signaling. Future work will include expression of each protein for use in assays to determine which are involved in pheromone binding, signaling and degradation. A sex pheromone analog has also been synthesized. Initial studies indicate that this analog acts as a repellant. Future work will determine its effectiveness as a disruptant of codling moth in orchards. The work reported here addresses objectives 1 and 2 in the parent project plan.