The circuit basis of olfactory mate recognition and localisation
type: CreativeWork
description: The circuit basis of olfactory mate recognition and localisation Finding a mate has two essential steps: recognising an appropriate partner and locating it. Sex pheromones are used in solving both tasks; they carry qualitative information to recognise, and positional information to locate a mate. How does the brain extract both a qualitative and a quantitative message from a single signal, like a pheromone smell? We used the pheromone sensing circuit of Drosophila melanogaster as a model to understand how such a signal is processed in the brain and how that instructs sexual behaviours. We used connectomics, functional imaging, and behavioural tests to investigate the anatomy and function of a circuitry dedicated to processing cis-vaccenyl acetate (cVA) a male pheromone signal. We discovered a previously unknown second order projection neuron class (PN) that senses cVA, and relays this signal to a neural hub for sexual behaviours - including female receptivity. We imaged the activity of sensory neurons and second order PNs in the cVA pathway while presenting the female with a male fly at defined positions and asked what features of the stimulus can be decoded from neuronal activity. We show that both sensory neurons and PNs carry information about male position by cell type-specific distance tuning properties and lateralisation ability. Additionally, we found an interneuron that is only activated by contralateral input and is well placed in the circuit to create mutual inhibition between the two sides. We propose that this mechanism underlies improved lateralisation in PNs compared to sensory neurons. To further understand cVA processing we characterised the responses of two third-order neurons. We found that one is selectively tuned to an approaching male, and the response magnitude is strongly dependent on approach speed. A second, previously described, sexually dimorphic third-order neuron receives taste input besides cVA, and integrates these signals at its dendr…
abstract: The circuit basis of olfactory mate recognition and localisation Finding a mate has two essential steps: recognising an appropriate partner and locating it. Sex pheromones are used in solving both tasks; they carry qualitative information to recognise, and positional information to locate a mate. How does the brain extract both a qualitative and a quantitative message from a single signal, like a pheromone smell? We used the pheromone sensing circuit of Drosophila melanogaster as a model to understand how such a signal is processed in the brain and how that instructs sexual behaviours. We used connectomics, functional imaging, and behavioural tests to investigate the anatomy and function of a circuitry dedicated to processing cis-vaccenyl acetate (cVA) a male pheromone signal. We discovered a previously unknown second order projection neuron class (PN) that senses cVA, and relays this signal to a neural hub for sexual behaviours - including female receptivity. We imaged the activity of sensory neurons and second order PNs in the cVA pathway while presenting the female with a male fly at defined positions and asked what features of the stimulus can be decoded from neuronal activity. We show that both sensory neurons and PNs carry information about male position by cell type-specific distance tuning properties and lateralisation ability. Additionally, we found an interneuron that is only activated by contralateral input and is well placed in the circuit to create mutual inhibition between the two sides. We propose that this mechanism underlies improved lateralisation in PNs compared to sensory neurons. To further understand cVA processing we characterised the responses of two third-order neurons. We found that one is selectively tuned to an approaching male, and the response magnitude is strongly dependent on approach speed. A second, previously described, sexually dimorphic third-order neuron receives taste input besides cVA, and integrates these signals at its dendr…
author: Taisz, István
language: eng
keywords: sensory processing, Drosophila melanogaster, sex pheromones, olfactory localisation, connectomics
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2021-06-30
date modified: 2026-07-22T22:24:04Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.84209