An IDS type sesquiterpene synthase produces the pheromone precursor (Z)-a-bisabolene in Nezara viridula

Authors: LANCASTER, JASON - Virginia Tech; LEHNER, BRYAN - Virginia Tech; Khrimian, Ashot; MUCHLINSKY, ANDREW - Virginia Tech; LUCK, KATRIN - Max Planck Institute Of Chemical Ecology; KOLLNER, TOBIAS - Max Planck Institute Of Chemical Ecology; Weber, Donald; Gundersen-Rindal, Dawn; THOLL, DOROTHEA - Virginia Tech

Submitted to: Journal of Chemical Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/20/2018
Publication Date: 9/29/2018
Citation: Lancaster, J., Lehner, B., Khrimian, A., Muchlinsky, A., Luck, K., Kollner, T., Weber, D.C., Gundersen, D.E., Tholl, D. 2018. An IDS type sesquiterpene synthase produces the pheromone precursor (Z)-a-bisabolene in Nezara viridula. Journal of Chemical Ecology. https://doi.org/10.1007/s10886-018-1019-0.
DOI: https://doi.org/10.1007/s10886-018-1019-0

Interpretive Summary: Stink bugs and other insects use volatile chemicals called pheromones for communication. If the communication systems of pest insects, and the way in which they make (synthesize) their pheromones, are known, pest managers might be able to suppress pest populations by trapping or disrupting mating and reproduction. This would provide a new strategy to reduce or eliminate pesticide applications for these pests. Males of the Southern green stink bug, a notorious agricultural pest with a worldwide distribution, produce a specific pheromone (called bisabolene oxide) attractive to females. In this study, we discovered an enzyme (called a NvTSP terpene sythase) unrelated to microbial or plant terpene synthases. This enzyme produces an important intermediate in the pheromone biosynthesis. Knowledge of pheromone biosynthesis in stink bugs may lead to the development of new controls of these pests. The study is of interest to researchers in entomology and biochemistry who are seeking practical, environmentally-friendly solutions for pest management.

Technical Abstract: Insects use a wide range of structurally diverse pheromones for intraspecific communication. Compounds in the class of terpenes are emitted as sex, aggregation, alarm, or trail pheromones. Despite the common occurrence of terpene pheromones in different insect lineages, their origin from dietary host plant precursors or de novo biosynthetic pathways often remains unknown. Several stink bugs (Hemiptera: Pentatomidae) release bisabolene-type sesquiterpenes for aggregation and mating. Here we provide evidence for de novo biosynthesis of the sex pheromone trans-/cis-a-(Z)-bisabolene epoxide of the Southern green stink bug, Nezara viridula. We show that an enzyme, designated NvTSP, related to isoprenyl diphosphate synthases (IDSs) of the core terpene metabolic pathway, functions as a terpene synthase (TPS), which converts the general intermediate (E,E)-farnesyl diphosphate (FPP) to the putative pheromone precursor a-(Z)-bisabolene in vitro and in protein lysates. A second identified IDS-type protein (NvFPPS) makes the TPS substrate (E,E)-FPP and functions as a bona fide FPP synthase. NvTPS is highly expressed in male epidermal tissue associated with the cuticle of ventral sternites, which is in agreement with the male-specific release of the pheromone from glandular cells in this tissue. Our study supports findings of the function of similar TPS enzymes in the biosynthesis of aggregation pheromones from the pine engraver beetle Ips pini, the striped flea beetle Phyllotreta striolata, and the harlequin bug Murgantia histrionica, and hence provides growing evidence for the evolution of terpene de novo biosynthesis by IDS-type TPS enzyme families in insects.