An odorant receptor and glomerulus responding to farnesene in Helicoverpa assulta (Lepidoptera: Noctuidae). (December 2019)

• Record Type: Journal Article
• Authors: Wu, Han; Li, Rui-Ting; Dong, Jun-Feng; Jiang, Nan-Ji; Huang, Ling-Qiao; Wang, Chen-Zhu
• Is Part Of: Insect biochemistry and molecular biology. Volume 115(2019)
• Publication Date: 2019-12
• Subjects: Farnesene -- Odorant receptor -- Glomeruli -- Labeled-line; Insect biochemistry -- Periodicals; Insects -- Physiology -- Periodicals; Insects -- Molecular aspects -- Periodicals; Biochemistry -- Periodicals; Insectes -- Biochimie -- Périodiques; Insectes -- Composition -- Périodiques; Insectes -- Physiologie -- Périodiques; Insectes -- Aspect moléculaire -- Périodiques; Biochimie -- Périodiques; Biochemistry; Insect biochemistry; Insects -- Molecular aspects; Insects -- Physiology; Periodicals; 572.8157
• DOI: 10.1016/j.ibmb.2018.11.006
• Languages: English
• ISSNs: 0965-1748

Abstract

Abstract: Terpenoids emitted from herbivore-damaged plants were found to play an important role in regulating tritrophic interactions. How herbivores and their natural enemies perceive terpenoids has not been thoroughly elucidated to date. Using in vivo calcium imaging, we found in this study that farnesene activates one glomerulus in the antennal lobe of female Helicoverpa assulta . The response induced by a mixture of farnesene isomers is stronger than that elicited by E-β-farnesene alone. In the Xenopus oocyte expression system, HassOR23/ORco is narrowly tuned to farnesene isomers and compounds with similar structures. Finally, the behavioral studies showed that the farnesene isomers have an inhibitory effect on oviposition of female H. assulta, but have an attractive effect on host searching of Campoletis chlorideae, the key endoparasitoid of H. assulta larvae. These results demonstrate that farnesene isomers are encoded by a labeled-line mode in the olfactory system of female H. assulta, suggesting that farnesene as a chemical signal from plants has important behavioral relevance and evolutionary implications in the tritrophic context. Graphical abstract: Image 1 Highlights: Farnesene isomers activated only a single glomerulus in the antennal lobe of female Helicoverpa assulta. HassOR23 was exclusively tuned to farnesene isomers and compounds with similar structures. Farnesene isomers were repulsive to H. assulta oviposition but attractive to the parasitoid Campoletis chlorideae.