Molecular basis of fatty acid taste in Drosophila

  1. Ji-Eun Ahn
  2. Yan Chen
  3. Hubert O Amrein  Is a corresponding author
  1. Texas A&M Health Science Center, United States

Abstract

Behavioral studies have established that Drosophila appetitive taste responses to towards fatty acids are mediated by sweet sensing Gustatory Receptor Neurons (GRNs). Here we show that sweet GRN activation requires the function of the Ionotropic Receptor genes IR25a, IR76b and IR56d. The former two IR genes are expressed in several neurons per sensilla, while IR56d expression is restricted to sweet GRNs. Importantly, loss of appetitive behavioral responses to fatty acids in IR25a and IR76b mutant flies can be completely rescued by expression of respective transgenes in sweet GRNs. Interestingly, appetitive behavioral responses of wild type flies to hexanoic acid reach a plateau at ~1%, but decreases with higher concentration, a property mediated through an IR25a/IR76b independent activation of bitter GRNs by hexanoic acid. With our previous report on sour taste, our studies suggest that IR-based receptors mediate different taste qualities through cell-type specific IR subunits.

Article and author information

Author details

  1. Ji-Eun Ahn

    Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Yan Chen

    Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Hubert O Amrein

    Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, United States
    For correspondence
    amrein@medicine.tamhsc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8799-7250

Funding

National Institutes of Health (RO1GMDC05606)

  • Hubert O Amrein

National Institutes of Health (RO1DC13967)

  • Hubert O Amrein

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

Reviewing Editor

  1. Mani Ramaswami, Trinity College Dublin, Ireland

Publication history

  1. Received: July 3, 2017
  2. Accepted: December 8, 2017
  3. Accepted Manuscript published: December 12, 2017 (version 1)
  4. Version of Record published: December 29, 2017 (version 2)

Copyright

© 2017, Ahn 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.

Metrics

  • 3,550
    Page views
  • 551
    Downloads
  • 41
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Ji-Eun Ahn
  2. Yan Chen
  3. Hubert O Amrein
(2017)
Molecular basis of fatty acid taste in Drosophila
eLife 6:e30115.
https://doi.org/10.7554/eLife.30115

Further reading

    1. Neuroscience
    Orie T Shafer et al.
    Research Article Updated

    The circadian clock orchestrates daily changes in physiology and behavior to ensure internal temporal order and optimal timing across the day. In animals, a central brain clock coordinates circadian rhythms throughout the body and is characterized by a remarkable robustness that depends on synaptic connections between constituent neurons. The clock neuron network of Drosophila, which shares network motifs with clock networks in the mammalian brain yet is built of many fewer neurons, offers a powerful model for understanding the network properties of circadian timekeeping. Here, we report an assessment of synaptic connectivity within a clock network, focusing on the critical lateral neuron (LN) clock neuron classes within the Janelia hemibrain dataset. Our results reveal that previously identified anatomical and functional subclasses of LNs represent distinct connectomic types. Moreover, we identify a small number of non-clock cell subtypes representing highly synaptically coupled nodes within the clock neuron network. This suggests that neurons lacking molecular timekeeping likely play integral roles within the circadian timekeeping network. To our knowledge, this represents the first comprehensive connectomic analysis of a circadian neuronal network.

    1. Neuroscience
    Ling Bai et al.
    Research Article Updated

    Animals must learn through experience which foods are nutritious and should be consumed, and which are toxic and should be avoided. Enteroendocrine cells (EECs) are the principal chemosensors in the GI tract, but investigation of their role in behavior has been limited by the difficulty of selectively targeting these cells in vivo. Here, we describe an intersectional genetic approach for manipulating EEC subtypes in behaving mice. We show that multiple EEC subtypes inhibit food intake but have different effects on learning. Conditioned flavor preference is driven by release of cholecystokinin whereas conditioned taste aversion is mediated by serotonin and substance P. These positive and negative valence signals are transmitted by vagal and spinal afferents, respectively. These findings establish a cellular basis for how chemosensing in the gut drives learning about food.