A gustatory receptor tuned to the steroid plant hormone brassinolide in Plutella xylostella (Lepidoptera: Plutellidae)
- Institute of Zoology, Chinese Academy of Sciences, China
Abstract
Feeding and oviposition deterrents help phytophagous insects to identify host plants. The taste organs of phytophagous insects contain bitter gustatory receptors (GRs). To explore their function, the GRs in Plutella xylostella were analyzed. Through RNA sequencing and qPCR, we detected abundant PxylGr34 transcripts in the larval head and adult antennae. Functional analyses using the Xenopus oocyte expression system and 24 diverse phytochemicals showed that PxylGr34 is tuned to the canonical plant hormones brassinolide (BL) and 24-epibrassinolide (EBL). Electrophysiological analyses revealed that the medial sensilla styloconica of 4th instar larvae are responsive to BL and EBL. Dual-choice bioassays demonstrated that BL inhibits larval feeding and female oviposition. Knock-down of PxylGr34 by RNAi attenuates the taste responses to BL, and abolishes BL-induced feeding inhibition. These results increase our understanding of how herbivorous insects detect compounds that deter feeding and oviposition, and may be useful for designing plant hormone-based pest management strategies.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all the figures.
Article and author information
Author details
Funding
National Natural Science Foundation of China (31830088)
- Chen-Zhu Wang
National Key R&D Program of China (2017YFD0200400)
- Chen-Zhu Wang
China Postdoctoral Science Foundation (2019M660792)
- Ke Yang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Kristin Scott, University of California, Berkeley, United States
Ethics
Animal experimentation: All procedures were approved by the Animal Care and Use Committee of theInstitute of Zoology, Chinese Academy of Sciences, and followed The Guidelines for the Care and Use of Laboratory Animals (protocol number: IOZ17090-A).
Version history
- Received: October 17, 2020
- Accepted: December 10, 2020
- Accepted Manuscript published: December 11, 2020 (version 1)
- Version of Record published: January 13, 2021 (version 2)
Copyright
© 2020, Yang 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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A gustatory receptor tuned to the steroid plant hormone brassinolide in Plutella xylostella (Lepidoptera: Plutellidae)
eLife 9:e64114.
https://doi.org/10.7554/eLife.64114
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