Internal states drive nutrient homeostasis by modulating exploration-exploitation trade-off

  1. Verónica María Corrales-Carvajal
  2. Aldo A Faisal
  3. Carlos Ribeiro  Is a corresponding author
  1. Champalimaud Centre for the Unknown, Portugal
  2. Imperial College London, United Kingdom

Abstract

Internal states can profoundly alter the behavior of animals. A quantitative understanding of the behavioral changes upon metabolic challenges is key to a mechanistic dissection of how animals maintain nutritional homeostasis. We used an automated video tracking setup to characterize how amino acid and reproductive states interact to shape exploitation and exploration decisions taken by adult Drosophila melanogaster. We find that these two states have specific effects on the decisions to stop at and leave proteinaceous food patches. Furthermore, the internal nutrient state defines the exploration-exploitation trade-off: nutrient-deprived flies focus on specific patches while satiated flies explore more globally. Finally, we show that olfaction mediates the efficient recognition of yeast as an appropriate protein source in mated females and that octopamine is specifically required to mediate homeostatic postmating responses without affecting internal nutrient sensing. Internal states therefore modulate specific aspects of exploitation and exploration to change nutrient selection.

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Author details

  1. Verónica María Corrales-Carvajal

    Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Lisbon, Portugal
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3813-5790
  2. Aldo A Faisal

    Department of Bioengineering, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Carlos Ribeiro

    Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Lisbon, Portugal
    For correspondence
    carlos.ribeiro@neuro.fchampalimaud.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9542-7335

Funding

Fundação para a Ciência e a Tecnologia (PTDC/BIA-BCM/118684/2010)

  • Carlos Ribeiro

Human Frontier Science Program (RGP0022/2012)

  • Aldo A Faisal
  • Carlos Ribeiro

Champalimaud Foundation

  • Verónica María Corrales-Carvajal
  • Carlos Ribeiro

Fundação para a Ciência e a Tecnologia (Graduate Student Fellowship, SFRH/BD/51113/2010)

  • Verónica María Corrales-Carvajal

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2016, Corrales-Carvajal 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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  1. Verónica María Corrales-Carvajal
  2. Aldo A Faisal
  3. Carlos Ribeiro
(2016)
Internal states drive nutrient homeostasis by modulating exploration-exploitation trade-off
eLife 5:e19920.
https://doi.org/10.7554/eLife.19920

Share this article

https://doi.org/10.7554/eLife.19920

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