A moth odorant receptor highly expressed in the ovipositor is involved in detecting host-plant volatiles
Abstract
Antennae are often considered to be the nostrils of insects. Here, we sequenced the transcriptome of the pheromone gland-ovipositor complex of Helicoverpa assulta and discovered that an odorant receptor (OR) gene, HassOR31, had much higher expression in the ovipositor than in antennae or other tissues. To determine whether the ovipositor was involved in odorant detection, we co-expressed HassOR31 and its co-receptor, HassORco, in a Xenopus oocyte model system, and demonstrated that the OR was responsive to 12 plant odorants, especially Z-3-hexenyl butyrate. These odorants elicited electrophysiological responses of some sensilla in the ovipositor, and HassOR31 and HassORco were co-expressed within ovipositor sensilla. Two oviposition preference experiments showed that female moths lacking antennae still preferentially selected oviposition sites containing plant volatiles. We suggest that the expression of HassOR31 in the ovipositor of H. assulta helps females to determine precise egg-laying sites in host plants.
Data availability
Sequencing data been uploaded to SRA database under PRJNA592822.
Article and author information
Author details
Funding
National Natural Science Foundation of China (31830088)
- Chen-Zhu Wang
National Natural Science Foundation of China (31772528)
- Chen-Zhu Wang
National Key R&D Program of China (2017YFD0200400)
- Chen-Zhu Wang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Marcel Dicke, Wageningen University, Netherlands
Ethics
Animal experimentation: All procedures in this study were approved by the Animal Care and Use Committee of the Institute of Zoology, Chinese Academy of Sciences for the care and use of laboratory animals (protocol number IOZ17090-A). The surgery was performed following the protocols reported by Nakagawa and Touhara (2013). The Xenopus laevis was anesthetized by bathed in the mixture of ice and water in 30 min, the wounds were carefully treated to avoid infection. Every effort was made to minimize suffering.
Version history
- Received: November 18, 2019
- Accepted: May 20, 2020
- Accepted Manuscript published: May 21, 2020 (version 1)
- Version of Record published: June 22, 2020 (version 2)
Copyright
© 2020, Li et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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