Excitation and inhibition onto central courtship neuronsbiases Drosophila mate choice
Abstract
The ability to distinguish males from females is essential for productive mate selection and species propagation. Recent studies in Drosophila have identified different classes of contact chemosensory neurons that detect female or male pheromones and influence courtship decisions. Here, we examine central neural pathways in the male brain that process female and male pheromones using anatomical, calcium imaging, optogenetic, and behavioral studies. We find that sensory neurons that detect female pheromones, but not male pheromones, activate a novel class of neurons in the ventral nerve cord to cause activation of P1 neurons, male-specific command neurons that trigger courtship. In addition, sensory neurons that detect male pheromones, as well as those that detect female pheromones, activate central mAL neurons to inhibit P1. These studies demonstrate that the balance of excitatory and inhibitory drives onto central courtship-promoting neurons controls mating decisions.
Article and author information
Author details
Reviewing Editor
- Mani Ramaswami, Trinity College Dublin, Ireland
Version history
- Received: August 27, 2015
- Accepted: November 12, 2015
- Accepted Manuscript published: November 14, 2015 (version 1)
- Accepted Manuscript updated: November 17, 2015 (version 2)
- Version of Record published: December 14, 2015 (version 3)
Copyright
© 2015, Kallman 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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