Distinct protocerebral neuropils associated with attractive and aversive female-produced odorants in the male moth brain
- Norwegian University of Science and Technology, Norway
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Chinese Academy of Agricultural Sciences, China
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, China
- Henan Agricultural University, China
Abstract
The pheromone system of heliothine moths is an optimal model for studying principles underlying higher-order olfactory processing. In Helicoverpa armigera, three male-specific glomeruli receive input about three female-produced signals, the primary pheromone component, serving as an attractant, and two minor constituents, serving a dual function, i.e. attraction versus inhibition of attraction. From the antennal-lobe glomeruli, the information is conveyed to higher olfactory centers, including the lateral protocerebrum, via three main paths – of which the medial tract is the most prominent. In this study, we traced physiologically identified medial-tract projection neurons from each of the three male‑specific glomeruli with the aim of mapping their terminal branches in the lateral protocerebrum. Our data suggest that the neurons’ wide-spread projections are organized according to behavioral significance, including a spatial separation of signals representing attraction versus inhibition – however, with a unique capacity of switching behavioral consequence based on the amount of the minor components.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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MGC_PNsInsect Brain Database.
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Data from: A Novel Major Output Target for Pheromone-Sensitive Projection Neurons in Male Mothswww.insectbrain.org; https://hdl.handle.net/20.500.12158/SIN-0000020.2.
Article and author information
Author details
Funding
Norges Forskningsråd (287052)
- Bente G Berg
National Natural Science Foundation of China (31861133019)
- GuiRong Wang
Science and technology innovation talents in University of Henan province (19HASTIT011)
- XinCheng Zhao
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: According to Norwegian law of animal welfare, there are no restrictions regarding experimental use of Lepidoptera.
Copyright
© 2021, Kymre 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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