1. Neuroscience

Identification of motor neurons and a mechanosensitive sensory neuron in the defecation circuitry of Drosophila larvae

  1. Wei Zhang
  2. Zhiqiang Yan
  3. Bingxue Li
  4. Lily Yeh Jan
  5. Yuh Nung Jan  Is a corresponding author
  1. Howard Hughes Medical Institute, University of California, San Francisco, United States
  2. Fudan University, China
https://doi.org/10.7554/eLife.03293
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  1. Wei Zhang
  2. Zhiqiang Yan
  3. Bingxue Li
  4. Lily Yeh Jan
  5. Yuh Nung Jan
(2014)
Identification of motor neurons and a mechanosensitive sensory neuron in the defecation circuitry of Drosophila larvae
eLife 3:e03293.
https://doi.org/10.7554/eLife.03293
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Abstract

Defecation allows the body to eliminate waste, an essential step in food processing for animal survival.In contrast to the extensive studies of feeding, its obligate counterpart, defecation, has received much less attention until recently. Here we report our characterizations of the defecation behavior of Drosophila larvae and its neural basis. Drosophila larvae display defecation cycles of stereotypic frequency, involving sequential contraction of hindgut and anal sphincter. The defecation behavior requires two groups of motor neurons that innervate hindgut and anal sphincter, respectively, and can excite gut muscles directly. These two groups of motor neurons fire sequentially with the same periodicity as the defecation behavior, as revealed by in vivo Ca2+ imaging. Moreover, we identified a single mechanosensitive sensory neuron that innervates the anal slit and senses the opening of the intestine terminus. This anus sensory neuron relies on the TRP channel NOMPC but not INACTIVE, NANCHUNG, or PIEZO for mechanotransduction.

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Author details

  1. Wei Zhang

    Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Zhiqiang Yan

    Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Bingxue Li

    Fudan University, Shanghai, China
    Competing interests
    The authors declare that no competing interests exist.

  4. Lily Yeh Jan

    Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Yuh Nung Jan

    Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
    For correspondence
    yuhnung.jan@ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Zhang 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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