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bioRxiv · 10.1101/2020.12.11.421289

Distinct protocerebral neuropils associated with attractive and aversive female-produced odorants in the male moth brain

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.

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Kymre, J. H., Liu, X., Ian, E., Berge, C. N., Zhao, X., Wang, G., Berg, B. G., Chu, X.. 2020-12-11. Distinct protocerebral neuropils associated with attractive and aversive female-produced odorants in the male moth brain. https://doi.org/10.1101/2020.12.11.421289

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